CCNA 3 Labs and Study Guide - BINARYBB.INFO – @jagalbraith

Switching Basics and Intermediate Routing
Cisco Press
800 East 96th Street
Indianapolis, Indiana 46240 USA
CCNA 3 Labs and Study Guide
Instructor Edition
Allan Johnson

ii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Switching Basics and Intermediate Routing
CCNA 3 Labs and Study Guide
Instructor Edition
Allan Johnson
Copyrigh® 2007 Cisco Systems, Inc.
Published by:
Cisco Press
800 East 96th Street
Indianapolis, IN 46240 USA
All rights reserved. No part of this book may be reproduced or transmitted
in any form or by any means, electronic or mechanical, including photocopying,
recording, or by any information storage and retrieval system,
without written permission from the publisher, except for the inclusion of
brief quotations in a review.
Printed in the United States of America 1 2 3 4 5 6 7 8 9 0
First Printing July 2006
Library of Congress Cataloging-in-Publication Number: 2006920177
ISBN: 1-58713-186-2
Warning and Disclaimer
This book is designed to provide information about the CCNA 3: Switching
Basics and Intermediate Routing course of the Cisco Networking Academy
Program CCNA curriculum. Every effort has been made to make this book
as complete and as accurate as possible, but no warranty or fitness is implied.
The information is provided on an “as is” basis. The authors, Cisco Press, and
Cisco Systems, Inc., shall have neither liability nor responsibility to any
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may accompany it.
The opinions expressed in this book belong to the author and are not necessarily
those of Cisco Systems, Inc.
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Cisco Press
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Andrew Cupp
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iv Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
About the Author
Allan Johnson entered the academic world in 1999 after 10 years as a business owner/operator to dedicate
his efforts to his passion for teaching. He has an MBA and an M.Ed in occupational training and development.
Allan is currently pursuing an MS in information security. He is an information technology instructor
at Mary Carroll High School and Del Mar College in Corpus Christi, Texas. Since 2003, Allan has
committed much of his time and energy to the CCNA Instructional Support Team providing services for
instructors worldwide and creating training materials. He is a familiar voice on the Cisco Networking
Academy Community forum, “Ask the Experts” series. He currently holds CCNA and CCAI certifications.
About the Technical Reviewer
Bernadette O’Brien has been teaching in the Cisco Networking Academy since 1998 in Schenectady,
New York. Schenectady High School is a Regional Academy for CCNA and a CATC for Sponsored
Curriculum, which Bernadette coordinates.
Bernadette received her BS degree from SUNY College at Buffalo and her MS degree in curriculum and
instruction from SUNY Albany. She is also CCNA and CCAI certified.
Bernadette, her husband, and two children live in a Victorian village very near the Adirondack Mountains
in upstate New York. They enjoy rehabbing their 120-year-old Victorian house, skiing, and hiking.

Dedications
To my wife Becky, and my daughter Christina. Thank you both for your love and patience.
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vi Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Acknowledgments
As technical editor, Bernadette O’Brien served admirably as my second pair of eyes, finding and correcting
technical inaccuracies as well as grammatical errors that helped make this project a first-class production.
Mary Beth Ray, executive editor, did an outstanding job from beginning to end steering this project
through to completion. I can always count on Mary Beth to make the tough decisions.
Andrew Cupp, development editor, has a dedication to perfection that pays dividends in countless, unseen
ways. Thank you for providing me much-needed guidance and support. This book could not be a reality
without your persistence.
Lastly, I cannot forget to thank all my students—past and present—who have helped me over the years to
create engaging and exciting activities and labs. There is no better way to test the effectiveness of an activity
than to give it to a team of dedicated students. They excel at finding the obscurest of errors! I could have
never done this without all of your support.

Contents at a Glance
Chapter 1: Introduction to Classless Routing 1
Chapter 2: Single-Area OSPF 99
Chapter 3: EIGRP and Troubleshooting Routing Protocols 175
Chapter 4: Switching Concepts 219
Chapter 5: LAN Design and Switches 233
Chapter 6: Catalyst Switch Configuration 243
Chapter 7: Spanning Tree Protocol 313
Chapter 8: Virtual LANs 341
Chapter 9: VLAN Trunking Protocol 379
Appendix A Router Interface Summary Chart 469
Appendix B Erasing and Reloading the Switch 471
Appendix C Erasing and Reloading the Router 473
Appendix D CCNA 3 Skills-Based Assessment Practice 475
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viii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Contents
Chapter 1: Introduction to Classless Routing 1
Study Guide 2
VLSM 2
Vocabulary Exercise: Matching 3
Vocabulary Exercise: Completion 4
Subnetting Review Exercises 4
Prefix Length Use Exercises 7
VLSM Subnetting a Subnet Exercises 9
VLSM Addressing Design Exercises 12
VLSM Addressing Design Scenarios 16
Summary Route Exercises 23
Default and Static Routing Scenario 30
Concept Questions 31
VLSM Case Study 32
RIP Version 2 34
Compare and Contrast Exercise 34
Internet Research 34
Lab Exercises 37
Command Reference 37
Curriculum Lab 1-1: Calculating VLSM Subnets (1.1.4) 37
Task 1: Divide the Allocated Addresses into Four Equal-Sized Address Blocks 38
Task 2: Allocate the Next Level After All the Requirements Are Met for the Higher
Level(s) 39
Task 3: Allocate Address Space for Sydney 39
Task 4: Allocate Address Space for Singapore 40
Task 5: Allocate Address Space for WAN Links 41
Curriculum Lab 1-2: Review of Basic Router Configuration with RIP
(1.2.3) 43
Task 1: Basic Router Configuration 45
Task 2: Start the HyperTerminal Program 45
Task 3: Name the HyperTerminal Session 45
Task 4: Specify the Computer’s Connecting Interface 45
Task 5: Specify the Interface Connection Properties 46
Task 6: Close the Session 48
Task 7: Reopen the HyperTerminal Connection 48
Task 8: Configure Hostname and Passwords on Router GAD 49
Task 9: Configure Interface Serial 0 on Router GAD 49
Task 10: Configure the Fast Ethernet 0 Interface on Router GAD 49
Task 11: Configure the IP Host Statements on Router GAD 49
Task 12: Configure RIP Routing on Router GAD 50
Task 13: Save the GAD Router Configuration 50
Task 14: Configure Hostname and Passwords on Router BHM 50
Task 15: Configure Interface Serial 0 on Router BHM 50

Task 16: Configure the Fast Ethernet 0 Interface on Router BHM 50
Task 17: Configure the IP Host Statements on Router BHM 51
Task 18: Configure RIP Routing on Router BHM 51
Task 19: Save the BHM Router Configuration 51
Task 20: Configure the Hosts 51
Task 21: Verify the Internetwork Is Functioning by Pinging the Fast Ethernet
Interface of the Other Router 51
Task 22: Show the Routing Tables for Each Router 52
Curriculum Lab 1-3: Converting RIPv1 to RIPv2 (1.2.4) 53
Task 1: Configure the Routers 54
Task 2: Configure the Routing Protocol on Router GAD 55
Task 3: Save the GAD Router Configuration 55
Task 4: Configure the Routing Protocol on Router BHM 55
Task 5: Save the BHM Router Configuration 55
Task 6: Configure the Hosts 56
Task 7: Verify that the Internetwork Is Functioning 56
Task 8: Enable RIPv2 Routing 56
Task 9: Ping All Interfaces on the Network from Each Host 56
Curriculum Lab 1-4: Verifying RIPv2 Configuration (1.2.5) 57
Task 1: Configure the Routers 58
Task 2: Configure the Routing Protocol on Router Gadsden 58
Task 3: Save the Gadsden Router Configuration 58
Task 4: Configure the Routing Protocol on Router BHM 58
Task 5: Save the BHM Router Configuration 58
Task 6: Configure the Hosts 58
Task 7: Verify that the Internetwork Is Functioning 59
Task 8: Show the Routing Tables for Each Router 59
Task 9: Enable RIPv2 Routing 60
Task 10: Show the Routing Tables 60
Task 11: Change the Fast Ethernet IP Subnet Mask on Router GAD 61
Task 12: Show the GAD Routing Table 61
Task 13: Show the BHM Routing Table 61
Task 14: Change the Network Addressing Scheme 62
Task 15: Show the Routing Table for Router GAD 62
Task 16: Show the Routing Table for Router BHM 63
Task 17: Change the Host Configurations 63
Task 18: Ping All Interfaces on the Network from Each Host 64
Task 19: Use show ip route to See Different Routes by Type 64
Task 20: Use the show ip protocol Command 64
Task 21: Remove the Version 2 Option for RIP 65
Task 22: Show the Routing Table for Router GAD 65
Task 23: Show the Routing Table for Router BHM 66
Curriculum Lab 1-5: Troubleshooting RIPv2 Using debug (1.2.6) 66
Task 1: Configure the Routers 67
Task 2: Configure the Routing Protocol on Router GAD 67
Task 3: Save the GAD Router Configuration 67
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Task 4: Configure the Routing Protocol on Router BHM 67
Task 5: Save the BHM Router Configuration 68
Task 6: Configure the Hosts 68
Task 7: Verify the Internetwork Is Functioning 68
Task 8: Show the debug ip Command Options 68
Task 9: Show the debug ip rip Command Options 69
Task 10: Show the RIP Routing Updates 69
Task 11: Enable RIPv2 Routing on Router GAD Only 69
Task 12: Restart the Debug Function on Router GAD 69
Task 13: Clear the Routing Table 70
Task 14: Start the Debug RIP Function 70
Task 15: Clear the Routing Table 70
Task 16: Enable RIPv2 Routing on Router BHM 71
Task 17: Use the Debug Function to See Packet Traffic on a Router 71
Task 18: Start the debug ip rip database Function on Router BHM 71
Task 19: Use the Debug Function to See Routing Updates 71
Comprehensive Lab 1-6: Default Routing and RIPv2 72
Task 1: Cable the Topology and Basic Configurations 73
Task 2: Configure Interfaces and Enable RIPv2 74
Task 3: Verify Connectivity 75
Task 4: Add ISP Router 76
Task 5: Configure Static and Default Routing 77
Task 6: Verify Connectivity and Capture Scripts 77
Challenge Lab 1-7: VLSM Design, RIPv2, and Default Routing 85
Task 1: Design the Addressing Scheme 86
Task 2: Cable the Topology and Basic Configurations 87
Task 3: Configure the Interfaces and Enable RIPv2 87
Task 4: Configure Static and Default Routing 87
Task 5: Verify Connectivity 88
Task 6: Challenge 89
Chapter 2: Single-Area OSPF 99
Study Guide 100
Link-State Routing Overview 100
Vocabulary Exercise: Matching 100
Vocabulary Exercise: Completion 101
Compare and Contrast Exercise 101
Concept Questions 102
Journal Entry 102
Single-Area OSPF Concepts 102
Vocabulary Exercise: Completion 102
Build the SPF Loop-Free Topology 103
Concept Questions 106
Single-Area OSPF Configuration 106
Learn the OSPF Commands Exercise 107

DR/BDR Election Exercise 114
Journal Entry 115
Lab Exercises 116
Command Reference 116
Curriculum Lab 2-1: Configuring the OSPF Routing Process (2.3.1)
117
Task 1: Configure the Routers 118
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
120
Task 3: Configure the Hosts 120
Task 4: View the Router’s Configuration and Interface Information 120
Task 5: Configure OSPF Routing on Router BERLIN 121
Task 6: Configure OSPF Routing on Router ROME 121
Task 7: Test Network Connectivity 122
Curriculum Lab 2-2: Configuring OSPF with Loopback Addresses
(2.3.2) 122
Task 1: Configure the Routers 123
Task 2: Save the Configuration Information for All the Routers 125
Task 3: Configure the Hosts 125
Task 4: View the Router’s Configuration and Interface Information 126
Task 5: Verify Connectivity of the Routers 126
Task 6: Configure OSPF Routing on Router London 126
Task 7: Configure OSPF Routing on Router Ottawa 127
Task 8: Configure OSPF Routing on Router Brasilia 127
Task 9: Test Network Connectivity 127
Task 10: Show OSPF Adjacencies 127
Task 11: Configure the Loopback Interfaces 128
Task 12: Save the Configuration Information for All the Routers 128
Task 13: Show OSPF Adjacencies 128
Task 14: Verify OSPF Interface Configuration 129
Task 15: Configure London to Always Be the DR 129
Task 16: Watch the Election Process 129
Task 17: Show OSPF Adjacencies 129
Curriculum Lab 2-3: Modifying OSPF Cost Metric (2.3.3) 130
Task 1: Configure the Routers 131
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
132
Task 3: Configure the Hosts 132
Task 4: View the Router’s Configuration and Interface Information 133
Task 5: Configure OSPF Routing on Router Cairo 134
Task 6: Configure OSPF Routing on the Moscow Router 134
Task 7: Show the Routing Table Entries 135
Task 8: Test Network Connectivity 135
Task 9: Look at the OSPF Cost on the Cairo Router Interfaces 135
Task 10: Record the OSPF Cost of the Serial and Fast Ethernet Interfaces 136
Task 11: Manually Set the Cost on the Serial Interface 136
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xii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 12: Verify Cost 136
Curriculum Lab 2-4: Configuring OSPF Authentication (2.3.4) 137
Task 1: Configure the Routers 138
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
140
Task 3: Configure the Hosts 140
Task 4: Verify Connectivity 140
Task 5: Configure OSPF Routing on Both Routers 140
Task 6: Test Network Connectivity 141
Task 7: Set Up OSPF Authentication 141
Task 8: Enable OSPF Authentication in this Area, Area 0 142
Curriculum Lab 2-5: Configuring OSPF Timers (2.3.5) 143
Task 1: Configure the Routers 144
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
145
Task 3: Configure the Hosts 145
Task 4: Verify Connectivity 146
Task 5: Configure OSPF Routing on both Routers 146
Task 6: Test Network Connectivity 146
Task 7: Observe OSPF Traffic 147
Task 8: Show Interface Timer Information 147
Task 9: Modify the OSPF Timers 147
Task 10: Examine the Routing Table 147
Task 11: Look at the OSPF Data Transmissions 147
Task 12: Check the Rome Router Routing Table Status 148
Task 13: Set the Rome Router Interval Timers 148
Task 14: Reset the Router’s Interval Timers to the Default Values 148
Task 15: Verify that the Interval Timers Are Returned to the Default Values 148
Curriculum Lab 2-6: Propagating Default Routes in an OSPF Domain
(2.3.6) 149
Task 1: Configure the ISP Router 150
Task 2: Configure the Area 0 OSPF Routers 151
Task 3: Save the Configuration Information from Privileged EXEC Command Mode
152
Task 4: Configure the Hosts 152
Task 5: Verify Connectivity 153
Task 6: Configure OSPF Routing on Both Area 0 Routers 153
Task 7: Test Network Connectivity 154
Task 8: Observe OSPF Traffic 154
Task 9: Create a Default Route to the ISP 154
Task 10: Verify the Default Static Route 154
Task 11: Verify Connectivity from the Madrid Router 155
Task 12: Verify Connectivity from the Tokyo Router 155
Task 13: Redistribute the Static Default Route 155

Comprehensive Lab 2-7: OSPF Configuration 156
Task 1: Cable the Topology and Basic Configurations 157
Task 2: Configure Interfaces and OSPF Routing 158
Task 3: Verify Connectivity 158
Task 4: Modify OSPF Cost 159
Task 5: Configure MD5 Authentication 160
Task 6: Adjust OSPF Timers 161
Task 7: Configure and Propagate a Default Route 162
Challenge Lab 2-8: OSPF Design and Configuration 167
Task 1: Design the Addressing Scheme 168
Task 2: Cable the Topology and Basic Configuration 169
Task 3: Configure OSPF Routing and Default Routing 169
Task 4: Other OSPF Configurations 169
Task 5: Verification and Documentation 170
Chapter 3: EIGRP and Troubleshooting Routing Protocols 175
Study Guide 176
EIGRP Concepts 176
Vocabulary Exercise: Matching 176
Vocabulary Exercise: Completion 177
EIGRP Packet Type Exercise 177
EIGRP Configuration 178
Learn the EIGRP Commands Exercise 178
Troubleshooting Routing Protocols 181
Problem-Solving Cycle 181
Troubleshooting RIP 182
Troubleshooting EIGRP 185
Troubleshooting OSPF 187
Internet Research Exercise 191
Lab Exercises 194
Command Reference 194
Curriculum Lab 3-1: Configuring EIGRP Routing (3.2.1) 195
Task 1: Configure the Routers 196
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
197
Task 3: Configure the Hosts 197
Task 4: View the Router’s Configuration and Interface Information 198
Task 5: Configure EIGRP Routing on Router Paris 198
Task 6: Configure EIGRP Routing on Router Warsaw 199
Task 7: Test Network Connectivity 199
Curriculum Lab 3-2: Verifying Basic EIGRP Configuration (3.2.3)
199
Task 1: Configure the Routers 200
Task 2: Save the Configuration Information from Privileged EXEC Command Mode
202
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xiv Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 3: Configure the Hosts 202
Task 4: View the Router’s Configuration and Interface Information 202
Task 5: Configure EIGRP Routing on Router Paris 203
Task 6: Configure EIGRP Routing on Router Warsaw 203
Task 7: Show EIGRP Neighbors 203
Task 8: Test Network Connectivity 203
Task 9: View the Topology Table 204
Comprehensive Lab 3-3: Comprehensive EIGRP Configuration 204
Task 1: Cable the Topology and Basic Configurations 205
Task 2: Configure Interfaces and EIGRP Routing 206
Task 3: Configure Bandwidth and Automatic Summarization 207
Task 4: Configure Manual Summarization 208
Challenge Lab 3-4: EIGRP Design and Configuration 209
Task 1: Design the Addressing Scheme 210
Task 2: Cable the Topology and Basic Configuration 211
Task 3: Configure EIGRP Routing and Default Routing 211
Task 4: Manual Summarization 212
Task 5: Verification and Documentation 212
Chapter 4: Switching Concepts 219
Study Guide 220
Introduction to Ethernet/802.3 LANs 220
Vocabulary Exercise: Matching 221
Vocabulary Exercise: Completion 222
CSMA/CD Process Flow Chart Exercise 223
Concept Questions 224
Journal Entry 224
Introduction to LAN Switching 225
Vocabulary Exercise: Completion 225
Building the MAC Address Table Exercise 225
Concept Questions 227
Journal Entry 227
Switch Operation 228
Vocabulary Exercise: Completion 228
Collision and Broadcast Domains Exercises 228
Choose the Correct Cable Exercise 230
Lab Exercises 231
Chapter 5: LAN Design and Switches 233
Study Guide 234
LAN Design 234
Vocabulary Exercise: Matching 234
Vocabulary Exercise: Completion 235
Concept Questions 236

LAN Switches 237
Vocabulary Exercise: Completion 237
Three-Layer Hierarchical Model Exercise 238
Concept Questions 240
Lab Exercises 241
Chapter 6: Catalyst Switch Configuration 243
Study Guide 244
Starting the Switch 244
Vocabulary Exercise: Completion 244
Switch LED Interpretation Exercise 245
Configuring the Switch 246
Learn Basic Switch Commands Exercise 246
Lab Exercises 249
Command Reference 249
Curriculum Lab 6-1: Verifying Default Switch Configuration (6.2.1)
250
Task 1: Enter Privileged Mode 251
Task 2: Examine the Current Switch Configuration 251
Task 3: Get Cisco IOS Software Information 252
Task 4: Examine the Fast Ethernet Interfaces 252
Task 5: Examine VLAN Information 253
Task 6: Examine Flash Memory (1900: Skip to Step 8) 253
Task 7: Examine the Startup Configuration File 254
Task 8: Exit the Switch 254
Curriculum Lab 6-2: Basic Switch Configuration (6.2.2) 255
Task 1: Enter Privileged Mode 256
Task 2: Examine the Current Switch Configuration 256
Task 3: Assign a Name to the Switch 258
Task 4: Examine the Current Running Configuration 259
Task 5: Set the Access Passwords (1900: Skip to Task 6) 261
Task 6: Set the Command Mode Passwords 261
Task 7: Configure Layer 3 Access to the Switch 261
Task 8: Verify the Management LAN Settings (1900: Skip to Step 9) 262
Task 9: Configure Port Speed and Duplex Properties for a Fast Ethernet Interface
262
Task 10: Verify the Settings on a Fast Ethernet Interface 263
Task 11: Save the Configuration 263
Task 12: Examine the Startup Configuration File (1900: Skip to Task 13) 264
Task 13: Remove the Enable and Enable Secret Passwords 266
Task 14: Access the Switch Web Interface 266
Task 15: Exit the Switch 267
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xvi Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 6-3: Managing the MAC Address Table (6.2.3) 267
Task 1: Configure the Switch 268
Task 2: Configure the Hosts that Are Attached to the Switch 268
Task 3: Verify Connectivity 268
Task 4: Record the Host MAC Addresses 268
Task 5: Determine the MAC Addresses that the Switch Has Learned 268
Task 6: Determine the show mac-address-table Options 269
Task 7: Clear the MAC Address Table 269
Task 8: Verify the Results 270
Task 9: Determine the clear mac-address-table Options 270
Task 10: Examine the MAC Table Again 270
Task 11: Exit the Switch 271
Curriculum Lab 6-4: Configuring Static MAC Addresses (6.2.4) 271
Task 1: Configure the Switch 272
Task 2: Configure the Hosts Attached to the Switch 272
Task 3: Verify Connectivity 272
Task 4: Record the Host MAC Addresses 272
Task 5: Determine the MAC Addresses that the Switch Has Learned 273
Task 6: Determine the mac-address-table Options 273
Task 7: Set Up a Static MAC Address 273
Task 8: Verify the Results 274
Task 9: Remove the Static MAC Entry 274
Task 10: Verify the Results 275
Task 11: Exit the Switch 275
Curriculum Lab 6-5: Configuring Port Security (6.2.5) 275
Task 1: Configure the Switch 276
Task 2: Configure the Hosts Attached to the Switch 276
Task 3: Verify Connectivity 276
Task 4: Record the Hosts’ MAC Addresses 276
Task 5: Determine the MAC Addresses that the Switch Has Learned 277
Task 6: Determine the mac-address-table Options 277
Task 7: Set Up a Static MAC Address 277
Task 8: Verify the Results 278
Task 9: List Port Security Options 278
Task 10: Verify the Results 279
Task 11: Show the Running Configuration File 279
Task 12: Limit the Number of Hosts Per Port 280
Task 13: Configure the Port to Shut Down if a Security Violation Occurs 280
Task 14: Show Port 0/4 Configuration Information 280
Task 15: Reactivate the Port 281
Task 16: Exit the Switch 281
Curriculum Lab 6-6: Add, Move, and Change MAC Addresses (6.2.6)
282
Task 1: Configure the Switch 283
Task 2: Configure the Hosts Attached to the Switch 283

Task 3: Verify Connectivity 283
Task 4: Record the Hosts’ MAC Addresses 283
Task 5: Determine the MAC Addresses that the Switch Has Learned 283
Task 6: Determine the mac-address-table Options 284
Task 7: Set Up a Static MAC Address 284
Task 8: Verify the Results 284
Task 9: List Port Security Options 285
Task 10: Verify the Results 285
Task 11: Show the Running Configuration File 286
Task 12: Limit the Number of Hosts Per Port 286
Task 13: Move Host 286
Task 14: Clear the MAC Address Table 287
Task 15: Change the Security Settings 287
Task 16: Verify the Results 288
Task 17: Exit the Switch 289
Curriculum Lab 6-7: Managing Switch Operating System Files (6.2.7a)
289
Task 1: Configure the Switch 290
Task 2: Configure the Host that Is Attached to the Switch 290
Task 3: Verify Connectivity 290
Task 4: Start and Configure the Cisco TFTP Server 290
Task 5: Copy the IOS Image to the TFTP Server (1900: Skip to Step 9) 291
Task 6: Verify the Transfer to the TFTP Server 291
Task 7: Copy the IOS Image from the TFTP Server 292
Task 8: Test the Restored IOS Image 292
Task 9: Procedure for 1900 Switch Firmware Upgrade Using TFTP 293
Curriculum Lab 6-8: Managing Switch Startup Configuration Files
(6.2.7b) 294
Task 1: Configure the Switch 295
Task 2: Configure the Host that Is Attached to the Switch 295
Task 3: Verify Connectivity 295
Task 4: Start and Configure the Cisco TFTP Server 295
Task 5: Copy the Startup Configuration File to the TFTP Server 296
Task 6: Verify the Transfer to the TFTP Server 297
Task 7: Restore the Startup Configuration File from the TFTP Server 297
Task 8: Test the Restored Startup Configuration Image (Not Supported on the 1900)
298
Curriculum Lab 6-9: Password Recovery Procedure on a Catalyst
2900 Series Switch (6.2.8) 300
Task 1: Configure the Switch 301
Task 2: Configure the Host that Is Attached to the Switch 301
Task 3: Verify Connectivity 301
Task 4: Reset the Console Password 301
Task 5: Recover Access to the Switch 301
Task 6: Restart the System 302
Task 7: Procedure for the 1900 and 2800 Switches 303
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xviii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 6-10: Firmware Upgrade of a Catalyst 2950 Series
Switch (6.2.9) 305
Task 1: Configure the Switch 306
Task 2: Configure the Host Attached to the Switch 306
Task 3: Verify Connectivity 306
Task 4: Display the Name of the Running Image File 306
Task 5: Prepare for the New Image 307
Task 6: Extract the New IOS Image and HTML Files into Flash Memory 307
Task 7: Associate the New Boot File 307
Task 8: Restart the Switch 308
Challenge Lab 6-11: Basic Switch Configuration with Port Security
308
Task 1: Cable the Topology and Clear the Configuration 309
Task 2: Configure the Switch 309
Task 3: Configure and Test Port Security 310
Chapter 7: Spanning Tree Protocol 313
Study Guide 314
Redundant Topologies 314
Vocabulary Exercise: Completion 314
Concept Questions 314
Journal Entry 315
Spanning Tree Protocol 315
Vocabulary Exercise: Matching 316
Vocabulary Exercise: Completion 317
Determine the Root Bridge and Port Roles Exercise 318
Spanning-Tree Recalculation Exercise 322
Concept Questions 323
Lab Exercises 324
Command Reference 324
Curriculum Lab 7-1: Selecting the Root Bridge (7.2.4) 324
Task 1: Configure the Switches 325
Task 2: Configure the Hosts that Are Attached to the Switches 325
Task 3: Verify Connectivity 325
Task 4: Look at the show interface vlan Options 326
Task 5: Look at the VLAN Interface Information 327
Task 6: Look at the Switches’ Spanning-Tree Tables 327
Task 7: Reassign the Root Bridge 329
Task 8: Look at the Switch Spanning-Tree Table 330
Task 9: Verify the Running Configuration File on the Root Switch 331
Curriculum Lab 7-2: Spanning-Tree Recalculation (7.2.6) 332
Task 1: Configure the Switches 333
Task 2: Configure the Hosts that Are Attached to the Switches 333
Task 3: Verify Connectivity 333
Task 4: Look at the VLAN Interface Information 333

Task 5: Look at the Switches’ Spanning-Tree Tables 334
Task 6: Remove a Cable on the Switch 336
Task 7: Look at the Spanning-Tree Table for the Switches 337
Task 8: Replace the Cable in the Switch 338
Task 9: Redisplay the Spanning-Tree Table for the Switches 338
Chapter 8: Virtual LANs 341
Study Guide 342
VLAN Concepts 342
Vocabulary Exercise: Completion 342
VLAN Configuration 342
Learn VLAN Configuration Commands Exercise 342
Troubleshooting VLANs 345
Identify the Troubleshooting Command Exercise 345
Lab Exercises 348
Command Reference 348
Curriculum Lab 8-1: Configuring Static VLANs (8.2.3) 348
Task 1: Configure the Switch 349
Task 2: Configure the Hosts Attached to the Switch 349
Task 3: Verify Connectivity 349
Task 4: Show the Cisco IOS Version 349
Task 5: Display the VLAN Interface Information 350
Task 6: Create and Name Two VLANs 351
Task 7: Display the VLAN Interface Information 351
Task 8: Assign a Port to VLAN 2 352
Task 9: Display the VLAN Interface Information 353
Task 10: Assign a Port to VLAN 3 354
Task 11: Display the VLAN Interface Information 354
Task 12: Look Only at VLAN 2 Information 355
Task 13: Look Only at VLAN 2 Information with a Different Command (1900: Skip
this Task) 355
Curriculum Lab 8-2: Verifying VLAN Configurations (8.2.4) 356
Task 1: Configure the Switch 357
Task 2: Configure the Hosts Attached to the Switch 357
Task 3: Verify Connectivity 357
Task 4: Display the VLAN Interface Information 357
Task 5: Create and Name Two VLANs 358
Task 6: Assign Ports to VLAN 2 358
Task 7: Display the VLAN Interface Information 359
Task 8: Assign Ports to VLAN 3 360
Task 9: Display the VLAN Interface Information 360
Task 10: Test the VLANs 361
Task 11: Move a Host 362
Task 12: Test the VLANs 362
Task 13: Move Hosts 362
xix

xx Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 14: Test the VLANs 362
Task 15: Move the Hosts 362
Task 16: Test the VLANs 362
Curriculum Lab 8-3: Deleting VLAN Configurations (8.2.6) 363
Task 1: Configure the Switch 364
Task 2: Configure the Hosts Attached to the Switch 364
Task 3: Verify Connectivity 364
Task 4: Display the VLAN Interface Information 364
Task 5: Create and Name Two VLANs 365
Task 6: Assign Ports to VLAN 2 365
Task 7: Display the VLAN Interface Information 366
Task 8: Assign Ports to VLAN 3 366
Task 9: Display the VLAN Interface Information 367
Task 10: Test the VLANs 368
Task 11: Delete a Host from a VLAN 368
Task 12: Display the VLAN Interface Information 368
Task 13: Delete a VLAN 369
Task 14: Display the VLAN Interface Information 370
Task 15: Delete VLAN 1 370
Challenge Lab 8-4: Static VLANs, STP, and Port Security 371
Task 1: Cable the Topology and Basic Configuration 371
Task 2: Configure VLANs 372
Task 3: Configure the Root Bridge for STP 373
Task 4: Configure Port Security 374
Task 5: Verify VLANs and Port Security 375
Chapter 9: VLAN Trunking Protocol 379
Study Guide 380
Trunking 380
Vocabulary Exercise: Completion 380
Basic Trunk Configuration Exercise 382
VTP 382
Vocabulary Exercise: Completion 383
VTP Basic Configuration Exercise 383
Concept Questions 384
Internet Research: VTP 385
Internet Research: VTP Pruning 387
Inter-VLAN Routing Overview 387
Vocabulary Exercise: Completion 387
Basic Inter-VLAN Configuration Exercise 388
Lab Exercises 389
Command Reference 389
Curriculum Lab 9-1: Trunking with ISL (9.1.5a) 391
Task 1: Configure the Switch 392

Task 2: Configure the Hosts Attached to the Switch 392
Task 3: Verify Connectivity 392
Task 4: Display the VLAN Interface Information 392
Task 5: Create and Name Three VLANs 393
Task 6: Assign Ports to VLAN 10 393
Task 7: Assign Ports to VLAN 20 394
Task 8: Assign Ports to VLAN 30 394
Task 9: Create VLANs on Switch_B 395
Task 10: Display the VLAN Interface Information 395
Task 11: Test the VLANs 396
Task 12: Create the ISL Trunk 396
Task 13: Verify the ISL Trunk 396
Task 14: Test the VLANs and the Trunk 397
Task 15: Move the Hosts 397
Task 16: Test the VLANs and the Trunk 397
Task 17: Move the Hosts 398
Task 18: Test the VLANs and the Trunk 398
Task 19: Move the Hosts 398
Task 20: Test the VLANs and the Trunk 398
Task 21: Move the Hosts 398
Task 22: Test the VLANs and the Trunk 398
Curriculum Lab 9-2: Trunking with 802.1q (9.1.5b) 402
Task 1: Configure the Switch 403
Task 2: Configure the Hosts Attached to the Switch 403
Task 3: Verify Connectivity 403
Task 4: Display the VLAN Interface Information 403
Task 5: Create and Name Three VLANs 404
Task 6: Assign Ports to VLAN 10 404
Task 7: Assign Ports to VLAN 20 405
Task 8: Assign Ports to VLAN 30 405
Task 9: Create VLANs on Switch_B 405
Task 10: Display the VLAN Interface Information 406
Task 11: Test the VLANs 406
Task 12: Create the Trunk 407
Task 13: Verify the Trunk 407
Task 14: Test the VLANs and the Trunk 408
Task 15: Move the Hosts 408
Task 16: Test the VLANs and the Trunk 409
Task 17: Move the Hosts 409
Task 18: Test the VLANs and the Trunk 409
Task 19: Move the Hosts 409
Task 20: Test the VLANs and the Trunk 410
Task 21: Move the Hosts 410
Task 22: Test the VLANs and the Trunk 410
xxi

xxii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 9-3: VTP Client and Server Configurations (9.2.5)
411
Task 1: Configure the Switches 412
Task 2: Configure the Hosts Attached to the Switch 412
Task 3: Verify Connectivity 412
Task 4: Display the VLAN Interface Information 412
Task 5: Configure VTP 413
Task 6: Create and Name Three VLANs 413
Task 7: Assign Ports to VLAN 10 414
Task 8: Assign Ports to VLAN 20 414
Task 9: Assign Ports to VLAN 30 414
Task 10: Display the VLAN Interface Information 415
Task 11: Configure the VTP Client 416
Task 12: Create the Trunk 416
Task 13: Verify the Trunk 416
Task 14: Display the VLAN Interface Information 417
Task 15: Assign Ports to VLAN 10 418
Task 16: Assign Ports to VLAN 20 418
Task 17: Assign Ports to VLAN 30 419
Task 18: Display the VLAN Interface Information 419
Task 19: Test the VLANs and the Trunk 420
Task 20: Move the Hosts 420
Task 21: Test the VLANs and the Trunk 420
Curriculum Lab 9-4: Configuring Inter-VLAN Routing (9.3.6) 421
Task 1: Configure the Switch 422
Task 2: Configure the Hosts Attached to the Switch 422
Task 3: Verify Connectivity 422
Task 4: Create and Name Two VLANs 422
Task 5: Assign Ports to VLAN 10 423
Task 6: Assign Ports to VLAN 20 423
Task 7: Display the VLAN Interface Information 424
Task 8: Create the Trunk 425
Task 9: Configure the Router 425
Task 10: Save the Router Configuration 426
Task 11: Display the Router Routing Table 426
Task 12: Test the VLANs and the Trunk 427
Task 13: Move the Hosts 427
Comprehensive Lab 9-5: Inter-VLAN and VTP Configuration 431
Task 1: Cable the Topology and Basic Configuration 432
Task 2: Configure VTP Parameters 432
Task 3: Configure Inter-VLAN Routing 435
Task 4: Adding, Moving, and Deleting VLANs 436
Task 5: Documentation 440

Challenge Lab 9-6: Advanced Switching 447
Task 1: Cable the Topology and Basic Configuration 448
Task 2: Configure the Root Bridge for STP 448
Task 3: Configure Port Security 449
Task 4: Configure VTP and VLANs 450
Task 5: Set Up DHCP on the DIST Router 453
Task 6: Configure Inter-VLAN Routing 453
Task 7: Verify Inter-VLAN Routing 454
Task 8: Documentation 458
Appendix A Router Interface Summary Chart 469
Appendix B Erasing and Reloading the Switch 471
Appendix C Erasing and Reloading the Router 473
Appendix D CCNA 3 Skills-Based Assessment Practice 475
xxiii

xxiv Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Icons Used in This Book
Communication
Server
Token
Ring
Token Ring
PC PC with
Software
Terminal File
Server
Command Syntax Conventions
The conventions that present command syntax in this book are the same conventions used in the IOS
Command Reference. The Command Reference describes these conventions as follows:
■ Boldface indicates commands and keywords that are entered literally as shown. In actual
configuration examples and output (not general command syntax), boldface indicates commands
that are manually input by the user (such as a show command).
■ Italics indicate arguments for which you supply actual values.
■ Vertical bars (|) separate alternative, mutually exclusive elements.
■ Square brackets [ ] indicate optional elements.
■ Braces { } indicate a required choice.
Sun
Workstation
Web
Server
Printer Laptop IBM
Mainframe
Gateway
Network Cloud
Macintosh
Cisco Works
Workstation
Front End
Processor
Access
Server
ATM
Switch
Cluster
Controller
■ Braces within brackets [{ }] indicate a required choice within an optional element.
ISDN/Frame Relay
Switch
Modem
Multilayer
Switch
Router Bridge Hub
DSU/CSU
DSU/CSU FDDI Catalyst
Switch
Line: Ethernet
FDDI
Line: Serial Line: Switched Serial

Introduction
Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide is a supplement to your classroom
and laboratory experience with the Cisco Networking Academy Program. Specifically, this book
covers the third of four courses. To be successful in this course and achieve your CCNA certification, you
should do everything in your power to arm yourself with a variety of tools and training materials to support
your learning efforts. This Labs and Study Guide is just such a collection of tools. Used to its fullest
extent, it will help you gain the knowledge as well as practice the skills associated with the content area of
the CCNA 3 Switching Basics and Intermediate Routing course. Specifically, this book will help you to
work on these main areas of CCNA 3:
■ Advanced IP addressing techniques (VLSM)
■ Routing protocols: RIPv2, single-area OSPF, and EIGRP
■ Switching technologies and LAN design
■ Switch configurations: security, STP, VLANs, and VTP
Lab Study Guides similar to this one are also available for the other three courses: Networking Basics
CCNA 1 Labs and Study Guide, Routers and Routing Basics CCNA 2 Labs and Study Guide, and WAN
Technologies CCNA 4 Labs and Study Guide.
Goals and Methods
One of the most important goals of this book is to help you prepare for either the CCNA exam (640-801)
or the ICND exam (640-811). Whether you are studying for the full exam or the second part of your
CCNA, passing either of these exams means that you not only have the required knowledge of the technologies
covered by the exam, but also can plan, design, implement, operate, and troubleshoot these technologies.
In other words, these exams are rigorously application-based. In fact, if you view the topics for
the CCNA exam at http://www.cisco.com/web/learning/le3/current_exams/640-801.html, you will see the
following four categories:
■ Planning & Designing
■ Implementation & Operation
■ Troubleshooting
■ Technology
Although Technology is listed last, a CCNA student cannot possibly plan, design, implement, operate, and
troubleshoot networks without first fully grasping the technology. So, you need to devote a certain amount
of time and effort in the Study Guide section of each chapter learning the concepts and theories before
applying them in the Lab Exercises portion.
The Study Guide section of each chapter offers exercises that help you learn the concepts and configurations
crucial to your success as a CCNA exam candidate. Each chapter is slightly different and includes
some or all of the following types of exercises:
■ Vocabulary matching and completion
■ Skill-building activities and scenarios
■ Configuration scenarios
■ Concept questions
■ Journal entries
■ Internet research
xxv

xxvi Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
The Lab Exercises sections include a Command Reference table, all the online Curriculum Labs, and
brand-new Comprehensive Labs and Challenge Labs. The Curriculum Labs typically walk you through the
configuration tasks step by step. The Comprehensive Labs combine many, if not all, of the configuration
tasks of the Curriculum Labs without actually providing you with all the commands. The Challenge Labs
take this a step further, often giving you only a general requirement that you must implement fully without
the details of each small step. In other words, you must use the knowledge and skills you gained in the
Curriculum Labs to successfully complete the Comprehensive and Challenge Labs. In fact, you should not
attempt the Comprehensive or Challenge Labs until you have worked through all the Study Guide activities
and the Curriculum Labs. When you work through the Comprehensive and Challenge Labs, avoid the
temptation to flip back through the Curriculum Labs when you are not sure of a command. Do not try to
short-circuit your CCNA training. Study the chapter’s topics until you can do the Comprehensive and
Challenge Labs without any help. You need a deep understanding of CCNA knowledge and skills to ultimately
be successful on the CCNA exam.
How This Book Is Organized
Although you could work through the Study Guides and Lab Exercises in this book in order, the content of
knowledge and skills actually flows down three separate paths. The flow chart shown in Figure I-1 graphically
displays these paths.
Figure I-1 Paths for Using This Book
Intermediate
Routing
Chapter 1:
Introduction to
Classless Routing
Chapter 2:
Single-Area
OSPF
Chapter 3:
EIGRP and
Troubleshooting
Routing Protocols
Intermediate
Routing and
Switching Basics
CCNA 3
Switching and
Design
Chapter 4:
Switching
Concepts
Chapter 5:
LAN Design
and Switches
Appendix D:
CCNA 3 Skills-Based
Assessment Practice
Switching
Configuration
Chapter 6:
Catalyst Switch
Configuration
Chapter 7:
Spanning Tree
Protocol
Chapter 8:
Virtual LANs
Chapter 9:
VLAN
Trunking Protocol
Chapters 1, 2, and 3 belong to the Intermediate Routing path and focus on VLSM and routing configuration.
Chapters 4 and 5 belong to the Switching and Design path and focus on switching technologies and
LAN design. Chapters 6, 7, 8, and 9 belong to the Switching Configuration path and focus on basic
switching protocols and configurations. No path is dependent upon another path. Appendix D provides you
with three different CCNA 3 Skills-Based Assessment practice labs.

Work through the Study Guide and Lab Exercises in the sequence in which they are presented. The
sequence is designed to take you from a basic understanding of the knowledge topics through the full
application and implementation of the skills. Individually, the chapters and appendixes include exercises
and labs covering the following knowledge and skills:
■ Chapter 1, “Introduction to Classless Routing”—Variable-Length Subnet Masking (VLSM) is
arguably one of the most challenging skills you must master as a CCNA candidate. Therefore, this
chapter spends a great deal of time on this topic. Use the large variety of exercises to solidify your
VLSM skills. In the RIPv2 discussion of the Study Guide portion, you compare and contrast RIPv1
and RIPv2 and complete an Internet Research exercise. In the Lab Exercises portion is a Command
Reference exercise to help you review all the commands covered in the chapter. The five Curriculum
Labs focus your attention on the configuration tasks covered in the chapter. Two additional labs, a
Comprehensive Lab and a Challenge Lab, help you review the commands and skills learned in the
Curriculum Labs.
■ Chapter 2, “Single-Area OSPF”—This chapter has plenty of vocabulary exercises to help you get a
firm grasp of OSPF terminology. Additional exercises focus on specific concepts and skills. For example,
the DR/BDR Election exercise concentrates on this challenging OSPF topic. Concept questions
round out your study of the operation of OSPF. In the Lab Exercises portion is a Command Reference
exercise to help you review all the commands covered in the chapter. The six Curriculum Labs focus
your attention on the configuration tasks covered in the chapter. Two additional labs, a Comprehensive
Lab and a Challenge Lab, help you review the commands and skills learned in the Curriculum Labs.
■ Chapter 3, “EIGRP and Troubleshooting Routing Protocols”—This chapter covers the concepts
and configurations of the Cisco-proprietary Enhanced Interior Gateway Routing Protocol (EIGRP).
Exercises cover vocabulary and the EIGRP packet types. In the “EIGRP Configuration” section, you
work through a comprehensive EIGRP configuration exercise. Finally, you work on your troubleshooting
skills in the “Troubleshooting Routing Protocols” section. The Lab Exercises portion has a
Command Reference exercise to help you review all the commands covered in the chapter. The two
Curriculum Labs focus your attention on the configuration tasks covered in the chapter. Two additional
labs, a Comprehensive Lab and a Challenge Lab, help you review the commands and skills learned
in the Curriculum Labs.
■ Chapter 4, “Switching Concepts”—This chapter is in many ways a review of concepts you have
already learned in previous course work. Therefore, in addition to some vocabulary exercises, additional
exercises concentrate on a few of the more difficult concepts, including CSMA/CD, the MAC
address table, collision and broadcast domains, and cabling. There are no Lab Exercises for this chapter.
■ Chapter 5, “LAN Design and Switches”—This chapter is mostly vocabulary and concepts. The
exercises in this chapter ensure that you have a firm grasp of the vocabulary and concepts pertaining
to LAN design and the three-layer hierarchical model. There are no Lab Exercises for this chapter.
xxvii
■ Chapter 6, “Catalyst Switch Configuration”—This chapter includes some vocabulary exercises and
LED switch identification exercises. Most of the Study Guide section is devoted to a basic switch configuration
exercise. In the Lab Exercises section of this chapter, you will find a Command Reference
exercise to help you review all the commands covered in the chapter. The ten Curriculum Labs focus
your attention on the configuration tasks covered in the chapter. A Challenge Lab will help you review
the commands and skills you learned in the Curriculum Labs.

xxviii Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
■ Chapter 7, “Spanning Tree Protocol”—This chapter covers the need for redundancy in today’s production
networks and explains how the Spanning Tree Protocol (STP) avoids switching loops in a
redundant configuration. Study Guide exercises include vocabulary, concept questions, determining
the root bridge, and spanning-tree recalculation. Because commands are limited to configuring the
root bridge and verifying STP operation, the Lab Exercises are limited to the two online Curriculum
Labs. However, STP configuration and verification commands are used in the Comprehensive and
Challenge Labs of both Chapter 8 and Chapter 9.
■ Chapter 8, “Virtual LANs”—This chapter begins the study of VLANs, which are increasingly
becoming more prominent in production networks. Exercises focus on vocabulary, concepts, configuration,
and troubleshooting. In the Lab Exercises section of this chapter, you will find a Command
Reference exercise to help you review all the commands covered in the chapter. The three Curriculum
Labs focus your attention on the configuration tasks covered in the chapter. An additional Challenge
Lab combines VLAN configuration with port security (Chapter 6) and STP (Chapter 7).
■ Chapter 9, “VLAN Trunking Protocol”—This chapter rounds out your CCNA study of VLANs
with the VLAN Trunking Protocol. Exercises include vocabulary, concept questions, Internet research,
and a journal entry. Also included are configuration exercises covering trunk configuration, VTP configuration,
and inter-VLAN configuration. In the Lab Exercises section of this chapter, you will find a
Command Reference exercise to help you review all the commands covered in the chapter. The four
Curriculum Labs focus your attention on the configuration tasks covered in the chapter. Two additional
labs, a Comprehensive Lab and a Challenge Lab, help you review the commands and skills learned
in the Curriculum Labs as well as reinforce commands from Chapters 6, 7, and 8.
■ Appendix A, “Router Interface Summary Chart”—This appendix has a table that you can reference
for the appropriate IOS interface names to use on Cisco 800, 1600, 1700, 2500, and 2600 series
routers.
■ Appendix B, “Erasing and Reloading the Switch”—Because many of the labs require a clean
switch configuration, this appendix includes the procedures you should complete before beginning.
■ Appendix C, “Erasing and Reloading the Router”—Because many of the labs require a clean
router configuration, this appendix includes the procedures you should complete before beginning.
■ Appendix D, “CCNA 3 Skills-Based Assessment Practice”—This appendix contains three practice
labs for the skills-based assessment. The first lab focuses on routing. The second lab focuses on
switching. The third lab is comprehensive, including most of the commands and configurations you
must master as a CCNA 3 student.

CHAPTER 1
Introduction to Classless Routing
The Study Guide portion of this chapter uses a combination of exercises to test your knowledge on classless
routing.
The Lab Exercises portion of this chapter includes all of the online curriculum labs as well as a
Comprehensive Lab and a Challenge Lab to ensure that you have mastered the practical, hands-on skills
needed about classless routing.

2 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
VLSM
Today’s networks must be stable yet scalable. Scalability means the initial design of the network must
allow for change and growth without any major modifications to the overall design. A key element of good
network design is an IP addressing plan that optimizes the use of IP addresses and minimizes the size of
routing tables. This is achieved through the use of VLSM, CIDR, and route summarization. These are fundamental
concepts and must be incorporated in your CCNA skill set before you move on to the more challenging
topics of OSPF and EIGRP, which both incorporate VLSM and scalable network design.
The exercises in this section will help you build your skills in implementing VLSM addressing schemes,
determining efficient route summaries, and configuring static and default routing. The exercises are meant
to progress logically from establishing the use of terminology in the Vocabulary Exercises through applying
your skill in design scenarios and application exercises. If you are new to the topic of VLSM, you
should proceed through the exercises in the order presented. However if you are refreshing your skill, try
one of the VLSM Addressing Design Scenarios or even Challenge Lab 1-7 to effectively gauge where you
are weak. Then, choose additional exercises to reinforce your knowledge and skill.

Vocabulary Exercise: Matching
Chapter 1: Introduction to Classless Routing 3
Match the definition on the left with a term on the right. This exercise is not necessarily a one-to-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
Definition
a. With classful routing, __________ must be
avoided because they are not visible across
classful network boundaries.
b. does not advertise subnet mask information.
c. describes the combination of multiple contiguous
classful network addresses into one
advertisement.
d. the policy of advertising routes at the classful
boundary.
e. When using a classful routing protocol, it is
important that all subnets have the same as
mask. This is sometimes referred to as
__________.
f. process of combining multiple subnets into
one advertisement with a common prefix
length (not necessarily on a classful boundary).
g. advertises subnet mask information.
h. When a router does not have an interface for
the destination network, it sends traffic to its
_____________.
i. With classless routing protocols, the subnet
mask can be different from subnet to subnet.
This is called __________.
j. also referred to as CIDR notation, bitmask,
and network mask, the number of bits that are
shared in common by all addresses in the
address space.
k. specified by RFC 1519 to address the critical
problems of exhaustion of Class B address
space and the growth in size of Internet routing
tables.
Term
k classless inter-domain routing
g classless routing protocol
j prefix length
a discontiguous subnets
f route aggregation
e fixed-length subnet masking (FLSM)
h default route
d automatic summarization
i variable-length subnet mask (VLSM)
f route summarization
c supernetting
b classful routing protocol

4 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Instructor Note: Supernetting can be referred to as route summarization or route aggregation, but route summarization
cannot always be referred to as supernetting. They are not technically the same thing. For example,
192.168.1.0/25 can be a summary route of the 192.168.1.0/26 and 192.168.1.64/26 subnets, but it is not a supernet of
them. Supernetting is a term used to describe the combination of multiple contiguous classful network addresses into
one advertisement. For example, 192.168.0.0/22 includes Class C networks 192.168.0.0 through 192.168.3.0.
However, the supernet 192.168.0.0/22 is more often referred to as a summary route. In fact, the show ip protocols
command will list this summary as Address Summarization, not as a supernet.
Classless inter-domain routing (CIDR, pronounced “cider”) is the method specified by RFC 1519 for assigning IP
addresses without using the standard IP address classes such as Class A, Class B, and Class C. Thus, an organization
could be assigned eight addresses such as 209.165.201.8/29. This is not a subnet; rather, it is a block of addresses from
209.165.201.8 through 209.165.201.15. The CIDR notation, which is the prefix length, is /29, meaning that the first
29 bits are assigned by the Internet Assigned Numbers Authority (http://www.iana.org). The remaining 3 bits are
available to the assignee for addressing purposes.
Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
When using classful routing protocols such as RIP and IGRP, you must use fixed-length subnet masking
(FLSM), which means that all subnets within the same addressing scheme must share the same subnet
mask. With these routing protocols, it is also very important to avoid discontiguous subnets, because they
perform automatic summarization at classful network boundaries. Subnets must be assigned to networks in
sequential order because they are not advertised across the network boundary.
Classless inter-domain routing is specified in RFC 1519 as a way to assign addresses by delineating the
prefix length of the common bits in the network portion of the address space instead of relying on the
default subnet masks of Classes A, B, and C.
The implementation of CIDR allows the use of classless routing protocols such as OSPF, IS-IS, EIGRP,
and BGPv4. These protocols effectively preserve address space and reduce the size of routing tables
through the use of variable-length subnet masks (or masking) (VLSM). These protocols are capable of
advertising a collection of classful addresses in one big supernet, which is a type of route summarization
(or aggregation) with which multiple address spaces can be combined into one route with a common network
prefix.
The process of using routing protocols such as RIP or OSPF is often referred to as dynamic routing. Two
other types of routing are available to the network administrator: static routing, which is the manual configuration
of a network/subnet mask combination, and default routing, which is the manual configuration
of a gateway of last resort.
Subnetting Review Exercises
Three basic subnetting review exercises follow, which will help you refresh your subnetting skills. You
must be able to demonstrate a basic level of competency in subnetting before proceeding into VLSM.
Note: CIDR notation refers to the practice of representing the prefix length of the network portion of an address in
“slash” format. For example, the CIDR notation of the Class C default subnet mask 255.255.255.0 is /24.

Class C Subnetting Scenario
Use the address space 192.168.1.0/24 and subnet it to provide enough addresses for 40 hosts.
What are the most bits you can borrow? 2
Assuming subnet 0 and the all-1s subnet are both useable, what is the total number of subnets? 4
What is the total number of useable hosts per subnet? 26 – 2 = 62
What is the new subnet mask in dotted-decimal notation? 255.255.255.192
What is the new subnet mask in CIDR notation? /26
What is the magic number or subnet multiplier? 64
Fill in the following table for the first ten useable subnets. All rows in the table may not be used.
Subnet No. Subnet Address Host Range Broadcast Address
0 192.168.1.0 192.168.1.1–192.168.1.62 192.168.1.63
1 192.168.1.64 192.168.1.65–192.168.1.126 192.168.1.127
2 192.168.1.128 192.168.1.129–192.168.1.190 192.168.1.191
3 192.168.1.192 192.168.1.193–192.168.1.254 192.168.1.255
4
5
6
7
8
9
Class B Subnetting Scenario
Use the address space 172.16.0.0/16 and subnet it to provide 2000 subnets.
How many bits do you need to borrow? 11
Assuming subnet 0 and the all-1s subnet are both useable, what is the total number of subnets? 2048
What is the total number of useable hosts per subnet? 25 – 2 = 30
What is the new subnet mask in dotted-decimal notation? 255.255.255.224
What is the new subnet mask in CIDR notation? /27
What is the magic number or subnet multiplier? 32
Chapter 1: Introduction to Classless Routing 5
Fill in the following table for the first ten useable subnets. Note: All blanks may not be used.

6 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Subnet No. Subnet Address Host Range Broadcast Address
0 172.16.0.32 172.16.0.33–172.16.0.62 172.16.0.63
1 172.16.0.64 172.16.0.65–172.16.0.94 172.16.0.95
2 172.16.0.96 172.16.0.97–172.16.0.126 172.16.0.127
3 172.16.0.128 172.16.0.129–172.16.0.158 172.16.0.159
4 172.16.0.160 172.16.0.161–172.16.0.190 172.16.0.191
5 172.16.0.192 172.16.0.193–172.16.0.222 172.16.0.223
6 172.16.0.224 172.16.0.225–172.16.0.254 172.16.0.255
7 172.16.1.0 172.16.1.1–172.16.1.30 172.16.1.31
8 172.16.1.32 172.16.1.33–172.16.1.64 172.16.1.63
9 172.16.1.64 172.16.1.65–172.16.1.94 172.16.1.95
Class A Subnetting Scenario
Use the address space 10.0.0.0/8 and subnet it to provide enough addresses for 30,000 hosts.
What are the most bits you can borrow? 9
Assuming subnet 0 and the all-1s subnet are both useable, what is the total number of subnets? 512
What is the total number of useable hosts per subnet? 215 – 2 = 32,764
What is the new subnet mask in dotted-decimal notation? 255.255.128.0
What is the new subnet mask in CIDR notation? /17
What is the magic number or subnet multiplier? 128
Fill in the following table for the first ten useable subnets. Note: All blanks may not be used.
Subnet No. Subnet Address Host Range Broadcast Address
0 10.0.0.0 10.0.0.1–10.0.127.254 10.0.127.255
1 10.0.128.0 10.0.128.1–10.0.255.254 10.0.255.255
2 10.1.0.0 10.1.0.1–10.1.127.254 10.1.127.255
3 10.1.128.0 10.1.128.1–10.1.255.254 10.1.255.255
4 10.2.0.0 10.2.0.1–10.2.127.254 10.2.127.255
5 10.2.128.0 10.2.128.1–10.2.255.254 10.2.255.255
6 10.3.0.0 10.3.0.1–10.3.127.254 10.3.127.255
7 10.3.128.0 10.3.128.1–10.3.255.254 10.3.255.255
8 10.4.0.0 10.4.0.1–10.4.127.254 10.4.127.255
9 10.4.128.0 10.4.128.1–10.4.255.254 10.4.255.255

Prefix Length Use Exercises
Use the following exercises to practice converting between dotted-decimal and prefix length representations
(CIDR notation) of subnet masks.
Dotted-Decimal to Prefix Length Conversion
Convert the following subnets and subnet masks shown in dotted-decimal format into the equivalent prefix
length format.
Example:
192.168.1.0 255.255.255.0; Answer: 192.168.1.0/24
192.168.1.0 255.255.255.128; Answer: 192.168.1.0/25
192.168.1.128 255.255.255.192; Answer: 192.168.1.0/26
192.168.1.32 255.255.255.224; Answer: 192.168.1.31/27
192.168.1.96 255.255.255.248; Answer: 192.168.1.96/29
192.168.1.48 255.255.255.252; Answer: 192.168.1.48/30
172.16.128.0 255.255.224.0; Answer: 172.16.128.0/19
172.16.8.0 255.255.255.128; Answer: 172.16.8.0/25
172.16.160.0 255.255.254.0; Answer: 172.16.160.0/23
172.16.80.0 255.255.240.0; Answer: 172.16.80.0/20
172.16.240.0 255.255.248.0; Answer: 172.16.240.0/21
172.16.39.0 255.255.255.0; Answer: 172.16.39.0/24
172.16.224.0 255.255.255.224; Answer: 172.16.224.0/27
172.16.45.24 255.255.255.248; Answer: 172.16.45.24/29
172.16.16.16 255.255.255.240; Answer: 172.16.16.16/28
172.16.200.192 255.255.255.192; Answer: 172.16.200.192/26
10.0.0.0 255.254.0.0; Answer: 10.0.0.0/15
10.5.160.32 255.255.255.224; Answer: 10.0.160.32/27
10.96.128.0 255.255.224.0; Answer: 10.96.128.0/19
10.64.48.0 255.255.255.240; Answer: 10.64.48.0/28
10.52.0.0 255.252.0.0; Answer: 10.52.0.0/14
Prefix Length to Dotted-Decimal Conversion
Convert the following subnets and subnet masks shown in prefix length format into the equivalent dotteddecimal
format.
Example:
172.16.0.0/16; Answer: 172.16.0.0 255.255.0.0
192.168.2.240/29; Answer: 192.168.2.240 255.255.255.248
192.168.2.32/28; Answer: 192.168.2.32 255.255.255.240
Chapter 1: Introduction to Classless Routing 7

8 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
192.168.2.0/25; Answer: 192.168.2.0 255.255.255.128
192.168.2.240/30; Answer: 192.168.2.240 255.255.255.252
192.168.2.192/26; Answer: 192.168.2.192 255.255.255.192
172.20.34.0/25; Answer: 172.20.34.0 255.255.255.128
172.20.64.0/18; Answer: 172.20.64.0 255.255.192.0
172.20.224.0/20; Answer: 172.20.224.0 255.255.240.0
172.20.16.0/23; Answer: 172.20.16.0 255.255.254.0
172.20.180.0/28; Answer: 172.20.180.0 255.255.255.240
172.20.36.0/22; Answer: 172.20.36.0 255.255.252.0
172.20.0.0/19; Answer: 172.20.0.0 255.255.224.0
172.20.128.0/17; Answer: 172.20.0.0 255.255.128.0
172.20.144.0/21; Answer: 172.20.144.0 255.255.248.0
172.20.96.96/27; Answer: 172.20.96.96 255.255.255.224
10.0.0.0/17; Answer: 10.0.0.0 255.255.128.0
10.0.154.32/28; Answer: 10.0.154.32 255.255.255.240
10.224.0.0/13; Answer: 10.72.224.0 255.248.0.0
10.32.0.0/22; Answer: 10.32.0.0 255.255.252.0
10.10.0.0/24; Answer: 10.10.0.0 255.255.255.0
Using Binary Math to AND the Subnet Address
Understanding how a router determines the network or subnet address for a given IP address is a fundamental
skill to implementing VLSM and interpreting routing tables.
In the following exercises, use binary math to “AND” the host IP address and subnet mask to determine
the subnet address. After completing the binary math, write the subnet address in dotted-decimal format.
In binary math, the AND operation is as follows:
1 AND 1 = 1; all other possibilities equal 0
Example:
192.168.1.67/28
IP address 11000000.10101000.00000001.01000011
Subnet mask 11111111.11111111.11111111.11110000
Subnet address 11000000.10101000.00000001.01000000
Dotted-decimal 192.168.1.64
1. 192.168.18.237/27
IP address 11000000.10101000.00010010.11101101
Subnet mask 11111111.11111111.11111111.11100000
Subnet address 11000000.10101000.00010010.11100000
Dotted-decimal 192.168.18.224

2. 192.168.35.142/29
IP address 11000000.10101000.00100011.10001110
Subnet mask 11111111.11111111.11111111.11111000
Subnet address 11000000.10101000.00100011.10000000
Dotted-decimal 192.168.35.128
3. 172.28.23.54/21
IP address 10101100.00011100.00010111.00110110
Subnet mask 11111111.11111111.11111000.00000000
Subnet address 10101100.00011100.00010000.00000000
Dotted-decimal 172.28.16.0
4. 172.31.32.69/25
IP address 10101100.00011111.00100000.01000101
Subnet mask 11111111.11111111.11111111.10000000
Subnet address 10101100.00011111.00100000.00000000
Dotted-decimal 172.31.32.0
5. 10.64.150.197/18
IP address 00001010.01000000.10010110.11000101
Subnet mask 11111111.11111111.11000000.00000000
Subnet address 00001010.01000000.10000000.00000000
Dotted-decimal 10.64.128.0
VLSM Subnetting a Subnet Exercises
Note: Now is a good time to complete Curriculum Lab 1-1: Calculating VLSM Subnets (1.1.4), which walks you
through a VLSM addressing scenario.
VLSM is simply “subnetting a subnet.” In the following exercises, use your subnetting skills to further
subnet a given subnet. If it helps you, draw a topology that represents the requirement you are given.
Example:
Chapter 1: Introduction to Classless Routing 9
Use the subnet 192.168.1.64/27 and further subnet this address to provide four additional subnets with at
least six hosts per subnet. List all four subnets in network address/prefix format.
Step 1. Determine how many host bits you have available in the given subnet. For subnet
192.168.1.64/27, you have a total of 5 host bits.
Step 2. Determine how many host bits you can borrow to make an additional four subnets with at least
six hosts per subnet. Borrowing an additional 2 bits will make four subnets (2 2 = 4). Because
there are 3 host bits left after borrowing, each subnet will have exactly six host addresses
(2 3 – 2 = 6).
Step 3. Determine the new prefix and list the new subnets. Because you borrowed 2 bits, the new
prefix is /29. You start with the first address 192.168.1.64 and list the four subnets.

10 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Subnet No. Network Address/Prefix
0 192.168.1.64/29
1 192.168.1.72/29
2 192.168.1.80/29
3 192.168.1.88/29
1. Use the subnet 192.168.1.128/25 and further subnet this address to provide eight additional subnets
with at least ten hosts per subnet. List the first five subnets in network address/prefix format. What
would be the last subnet?
192.168.1.240/28
Subnet No. Network Address/Prefix
0 192.168.1.128/28
1 192.168.1.144/28
2 192.168.1.160/28
3 192.168.1.176/28
4 192.168.1.192/28
2. Use the subnet 172.16.32.0/19 and further subnet this address to provide eight additional subnets with
at least 1000 hosts per subnet. List the first five subnets in network address/prefix format. What would
be the last subnet?
172.16.60/22
Subnet No. Network Address/Prefix
0 172.16.32.0/22
1 172.16.36.0/22
2 172.16.40.0/22
3 172.16.44.0/22
4 172.16.48.0/22
3. Use subnet 2 from the last question and further subnet this address to provide eight additional subnets
with at least 100 hosts per subnet. List the first five subnets in network address/prefix format. What
would be the last subnet?
172.16.43.128/25
Subnet No. Network Address/Prefix
0 172.16.40.0/25
1 172.16.40.128/25
2 172.16.41.0/25
3 172.16.41.128/25
4 172.16.42.0/25

4. Use subnet 4 from the last question and further subnet this address to provide eight additional subnets
with at least ten hosts per subnet. List the first five subnets in network address/prefix format. What
would be the last subnet?
172.16.42.112/28
Subnet No. Network Address/Prefix
0 172.16.42.0/28
1 172.16.42.16/28
2 172.16.42.32/28
3 172.16.42.48/28
4 172.16.42.64/28
5. Use subnet 0 from the last question and further subnet this address to provide four additional subnets
to be used for point-to-point links. List all four subnets in network address/prefix format.
Subnet No. Network Address/Prefix
0 172.16.42.0/30
1 172.16.42.4/30
2 172.16.42.8/30
3 172.16.42.12/30
6. Use the subnet 10.1.0.0/16 and further subnet this address to provide 30 additional subnets with at
least 2000 hosts per subnet. List the first five subnets in network address/prefix format. What would
be the last subnet?
10.1.248.0/21
Subnet No. Network Address/Prefix
0 10.1.0.0/21
1 10.1.8.0/21
2 10.1.16.0/21
3 10.1.24.0/21
4 10.1.32.0/21
Chapter 1: Introduction to Classless Routing 11

12 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
7. Use subnet 4 from the last question and further subnet this address to provide 30 additional subnets
with at least 60 hosts per subnet. List the first five subnets in network address/prefix format. What
would be the last subnet?
10.1.39.192.0/26
Subnet No. Network Address/Prefix
0 10.1.32.0/26
1 10.1.32.64/26
2 10.1.32.128/26
3 10.1.32.192/26
4 10.1.33.0/26
8. Use subnet 1 from the last question and further subnet this address to provide 16 additional subnets to
be used for point-to-point links. List the first 5 subnets in network address/prefix format. What would
be the last subnet?
10.1.32.124/30
Subnet No. Network Address/Prefix
0 10.1.32.64/30
1 10.1.32.68/30
2 10.1.32.72/30
3 10.1.32.76/30
4 10.1.32.80/30
VLSM Addressing Design Exercises
In the following VLSM Addressing Design Exercises, you apply your VLSM addressing skills to a three
router topology. Each exercise is progressively more difficult than the last. There may be more than one
correct answer in some situations. However, you should always practice good addressing design by assigning
your subnets contiguously. This allows the summary of a group of subnets into one aggregate route,
thus decreasing the size of routing tables.
VLSM Addressing Design Exercise 1
Assume that 4 bits were borrowed from the host portion of 192.168.1.0/24. You are not using VLSM.
Starting with subnet 0, label Figure 1-1 contiguously with subnets. Start with the LAN on RTA and proceed
clockwise.

Figure 1-1 Addressing Design Exercise 1 Topology: Subnets
Address Space
192.168.1.0/24
192.168.1.64/28
192.168.1.80/28
192.168.1.0/28
RTA
RTC RTB
192.168.1.48/28
How many total valid host addresses will be wasted on the WAN links?
You assigned 3 WAN subnets with 14 hosts each. Two hosts are used. Therefore, 12 hosts × 3 WAN subnets
= 36 wasted host addresses.
Now, come up with a better addressing scheme using VLSM. Start with the same 4 bits borrowed from the
host portion of 192.168.1.0/24. Label each of the LANs with a subnet. Then, subnet the next available subnet
to provide WAN subnets without wasting any host addresses. Label Figure 1-2 with the subnets.
Figure 1-2 Addressing Design Exercise 1 Topology: VLSM Subnets
Address Space
192.168.1.0/24
192.168.1.32/28
192.168.1.56/30
192.168.1.0/28
RTA
Chapter 1: Introduction to Classless Routing 13
192.168.1.16/28
192.168.1.48/30
RTC RTB
192.168.1.52/30
192.168.1.32/28
192.168.1.16/28

14 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
List the address space that is still available for future expansion.
For the solution shown in Figure 1-2, address space still available is .60/30; .64/26; .128/25.
The topology shown in Figure 1-3 has LAN subnets already assigned out of the 192.168.1.0/24 address
space. Using VLSM, create and label the WANs with subnets from the remaining address space.
Figure 1-3 Addressing Design Exercise 1 Topology: WAN Subnets
Address Space
192.168.1.0/24
192.168.1.128/27
List the address space that is still available for future expansion.
Answers may vary. In the answer shown in Figure 1-3, the available address space is .172/30; .176/28;
.192/26.
VLSM Addressing Design Exercise 2
192.168.1.0/26
RTA
192.168.1.168/30 192.168.1.160/30
RTC RTB
192.168.1.164/30
Your address space is 192.168.1.192/26. Each LAN needs to support ten hosts. Use VLSM to create a contiguous
IP addressing scheme. Label Figure 1-4 with your addressing scheme. Don’t forget the WAN links.
Figure 1-4 Addressing Design Exercise 2 Topology
Address Space
192.168.1.192/26
192.168.1.224/28
192.168.1.248/30
192.168.1.192/28
RTA
192.168.240./30
RTC RTB
192.168.1.244/30
192.168.1.64/26
192.168.1.208/28

List the address space that is still available for future expansion.
There is only one subnet left: .252/30.
VLSM Addressing Design Exercise 3
Your address space is 192.168.6.0/23. The number of hosts needed for each LAN is shown in Figure 1-5.
Use VLSM to create a contiguous IP addressing scheme. Label Figure 1-5 with your addressing scheme.
Don’t forget the WAN links.
Figure 1-5 Addressing Design Exercise 3 Topology
Address Space
192.168.6.0/23
192.168.7.64/27
30 Hosts
192.168.7.104/30
List the address space that is still available for future expansion.
For the solution shown in Figure 1-5, the address space still available is .7.108/30; .7.112/28; .7.128/25.
VLSM Addressing Design Exercise 4
192.168.6.0/24
150 Hosts
RTA
RTC RTB
192.168.7.100/30
Chapter 1: Introduction to Classless Routing 15
192.168.7.96/30
192.168.7.0/26
60 Hosts
Your address space is 10.10.96.0/21. The number of hosts needed for each LAN is shown in Figure 1-6.
Use VLSM to create a contiguous IP addressing scheme. Label Figure 1-6 with your addressing scheme.
Don’t forget the WAN links.

16 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-6 Addressing Design Exercise 4 Topology
Address Space
10.10.96.0/21
10.10.102.0/24
250 Hosts
10.10.103.248/30
List the address space that is still available for future expansion.
For the solution shown in Figure 1-6, the address space still available is .103.252/30; .103.224/28;
.103.192/27; .103.128/26; .103.0/25.
VLSM Addressing Design Scenarios
The following VLSM Addressing Design Scenarios will build upon your addressing design skills. In these
scenarios, you will fully document your network design, including IP addresses for interfaces and hosts.
Instructor Note: Once students have successfully completed a scenario, have them test it out on real routers or a simulator
such as Packet Tracer.
VLSM Addressing Design Scenario 1
Complete Addressing Design Scenario 1 using the following list of requirements:
■ Address space: 192.168.1.0/25.
10.10.96.0/22
1,000 Hosts
RTA
RTC RTB
10.10.103.244/30
■ RTA LAN, 60 hosts; RTB LAN, 30 hosts; RTC LAN, 10 hosts.
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in Figure 1-7.
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
10.10.103.240/30
10.10.100.0/23
500 Hosts

Figure 1-7 Addressing Design Scenario 1 Topology
For the solution shown in Figure 1-7, the address space still available is .124/30.
Because the given address space is /25, there is no more available space except for the one leftover WAN
subnet.
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 192.168.1.1 255.255.255.192
S0/1 192.168.1.113 255.255.255.252
S0/0 192.168.1.121 255.255.255.252
RTB Fa0/0 192.168.1.65 255.255.255.224
S0/1 192.168.1.114 255.255.255.252
S0/0 192.168.1.117 255.255.255.252
RTC Fa0/0 192.168.1.97 255.255.255.240
S0/1 192.168.1.118 255.255.255.252
S0/0 192.168.1.122 255.255.255.252
Host A 192.168.1.2 255.255.255.192 192.168.1.1
Host B 192.168.1.66 255.255.255.224 192.168.1.65
Host C 192.168.1.98 255.255.255.240 192.168.1.97
VLSM Addressing Design Scenario 2
Complete Addressing Design Scenario 2 using the following list of requirements:
■ Address space: 192.168.18.0/23.
Fa0/0
RTA
Fa0/0 Fa0/0
RTC
S0/1
S0/0
DCE
RTB
192.168.1.116/30
■ RTA LAN, 250 hosts; RTB LAN, 100 hosts; RTC LAN, 60 hosts.
S0/0
Chapter 1: Introduction to Classless Routing 17
60 Hosts
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in Figure 1-8.
S0/1
DCE
S0/0
C DCE
S0/1
B
10 Hosts
Address Space
192.168.1.0/25
192.168.1.96/28
192.168.1.120/30
192.168.1.0/26
A
192.168.1.112/30
192.168.1.64/27
30 Hosts

18 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
Figure 1-8 Addressing Design Scenario 2 Topology
Fa0/0 Fa0/0
RTC
S0/1
S0/0
DCE
RTB
192.168.19.196/30
For the solution shown in Figure 1-8, the address space still available is .19.204/30; .19.208/28;
.19.224/27.
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 192.168.18.1 255.255.255.0
S0/1 192.168.19.193 255.255.255.252
S0/0 192.168.19.201 255.255.255.252
RTB Fa0/0 192.168.19.1 255.255.255.128
S0/1 192.168.19.194 255.255.255.252
S0/0 192.168.19.197 255.255.255.252
RTC Fa0/0 192.168.19.129 255.255.255.192
S0/0
S0/1 192.168.19.198 255.255.255.252
S0/0 192.168.19.202 255.255.255.252
Host A 192.168.18.2 255.255.255.0 192.168.18.1
Host B 192.168.19.2 255.255.255.128 192.168.19.1
Fa0/0
Host C 192.168.19.130 255.255.255.192 192.168.19.129
RTA
250 Hosts
S0/1
DCE
C
S0/0
DCE
S0/1
B
60 Hosts
Address Space
192.168.18.0/23
192.168.19.128/26
192.168.19.200/30
192.168.18.0/24
A
192.168.19.192/30
192.168.19.0/25
100 Hosts

VLSM Addressing Design Scenario 3
Complete Addressing Design Scenario 3 using the following list of requirements:
■ Address space: 172.16.0.0/22.
■ RTA LAN, 500 hosts; RTB LAN, 250 hosts; RTC LAN, 100 hosts.
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in Figure 1-9.
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
Figure 1-9 Addressing Design Scenario 3 Topology
Fa0/0 Fa0/0
RTC
S0/1
S0/0
DCE
RTB
172.16.3.132/30
For the solution shown in Figure 1-9, the address space still available is .3.140/30; .3.144/28; .3.160/27;
.3.192/27.
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 172.16.0.1 255.255.254.0
S0/1 172.16.3.129 255.255.255.252
S0/0 172.16.3.137 255.255.255.252
RTB Fa0/0 172.16.2.1 255.255.255.0
S0/1 172.16.3.130 255.255.255.252
S0/0 172.16.3.133 255.255.255.252
RTC Fa0/0 172.16.3.1 255.255.255.128
S0/1 172.16.3.134 255.255.255.252
S0/0 172.16.3.138 255.255.255.252
Chapter 1: Introduction to Classless Routing 19
Host A 172.16.0.2 255.255.254.0 172.16.0.1
Host B 172.16.2.2 255.255.255.0 172.16.2.1
Host C 172.16.3.2 255.255.255.128 172.16.3.1
S0/0
Fa0/0
RTA
500 Hosts
S0/1
DCE
S0/0
C DCE
S0/1
B
100 Hosts
Address Space
172.16.0.0/22
172.16.3.0/25
172.16.3.136/30
172.16.0.0/23
A
172.16.3.128/30
172.16.2.0/24
250 Hosts

20 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
VLSM Addressing Design Scenario 4
Complete Addressing Design Scenario 4 using the following list of requirements:
■ Address space: 172.24.0.0/21.
■ RTA LAN, 1000 hosts; RTB LAN, 500 hosts; RTC LAN, 250 hosts.
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in
Figure 1-10.
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
Figure 1-10 Addressing Design Scenario 4 Topology
Fa0/0 Fa0/0
RTC
S0/1
S0/0
DCE
RTB
172.24.7.4/30
For the solution shown in Figure 1-10, the address space still available is .7.12/30; .7.16/28; .7.32/27;
.7.64/26; .7.128/25.
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 172.24.0.1 255.255.252.0
S0/1 172.24.7.1 255.255.255.252
S0/0 172.24.7.9 255.255.255.252
RTB Fa0/0 172.24.4.1 255.255.254.0
S0/1 172.24.7.2 255.255.255.252
S0/0 172.24.7.5 255.255.255.252
RTC Fa0/0 172.24.6.1 255.255.255.0
S0/0
S0/1 172.24.7.6 255.255.255.252
S0/0 172.24.7.10 255.255.255.252
Host A 172.24.0.2 255.255.252.0 172.24.0.1
Fa0/0
RTA
1,000 Hosts
S0/1
DCE
S0/0
C DCE
S0/1
B
250 Hosts
Address Space
172.24.0.0/21
172.24.0.0/22
A
172.24.7.8/30 172.24.7.0/30
172.24.6.0/24 172.24.4.0/23
500 Hosts

Device Interface IP Address Subnet Mask Default Gateway
Host B 172.24.4.2 255.255.254.0 172.24.4.1
Host C 172.24.6.2 255.255.255.0 172.24.6.1
VLSM Addressing Design Scenario 5
Complete Addressing Design Scenario 5 using the following list of requirements:
■ Address space: 10.8.64.0/18.
■ RTA LAN, 6000 hosts; RTB LAN, 3000 hosts; RTC LAN, 1000 hosts.
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in Figure 1-11.
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
Figure 1-11 Addressing Design Scenario 5 Topology
Fa0/0
Fa0/0 Fa0/0
RTC
S0/1
S0/0 RTB
10.8.116.4/30
DCE
For the solution shown in Figure 1-11, the address space still available is 116.12/30; .116.16/28;
.116.32/27; .116.64/26; .116.128/25; .117.0/24; .118.0/23; .120.0/21.
RTA
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 10.8.64.1 255.255.224.0
S0/1 10.8.116.1 255.255.255.252
S0/0 10.8.116.9 255.255.255.252
RTB Fa0/0 10.8.96.1 255.255.240.0
S0/0
S0/1 10.8.116.2 255.255.255.252
S0/0 10.8.116.5 255.255.255.252
Chapter 1: Introduction to Classless Routing 21
6,000 Hosts
S0/1
DCE
S0/0
C DCE
S0/1
B
1,000 Hosts
Address Space
10.8.64.0/18
10.8.116.8/30
10.8.64.0/19
A
10.8.116.0/30
10.8.112.0/22 10.8.96.0/20
3,000 Hosts

22 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Device Interface IP Address Subnet Mask Default Gateway
RTC Fa0/0 10.8.112.1 255.255.252.0
S0/1 10.8.116.6 255.255.255.252
S0/0 10.8.116.10 255.255.255.252
Host A 10.8.64.2 255.255.224.0 10.8.64.1
Host B 10.8.96.2 255.255.240.0 10.8.96.1
Host C 10.8.112.2 255.255.252.0 10.8.112.1
VLSM Addressing Design Scenario 6
Complete Addressing Design Scenario 6 using the following list of requirements:
■ Address space: 10.0.0.0/15.
■ RTA LAN, 65,000 hosts; RTB LAN, 30,000 hosts; RTC LAN, 8000 hosts.
■ Using good VLSM design practices, contiguously assign subnets to the topology shown in Figure 1-12.
■ Fill in the table with all necessary IP address configuration information for all devices. Use dotteddecimal
format for the subnet mask.
■ List the address space that is still available for future expansion.
Figure 1-12 Addressing Design Scenario 6 Topology
S0/0
Fa0/0
RTA
65,000 Hosts
S0/1
DCE
S0/0
C DCE
S0/1
B
8,000 Hosts
Address Space
10.0.0.0/15
10.1.128.0/19
10.1.160.8/30
10.0.0.0/16
A
10.1.160.0/30
Fa0/0 Fa0/0
RTC
S0/1
S0/0
DCE
RTB
10.1.160.4/30
10.1.0.0/17
30,000 Hosts

For the solution shown in Figure 1-12, the address space still available is 10.1.160.12/30; 10.1.160.16/28;
10.1.160.32/27; 10.1.160.64/26; 10.1.160.128/25; 10.1.161.0/24; 10.1.162.0/23; 10.1.164.0/22;
10.1.168.0/21; 10.1.176.0/20; 10.1.192.0/18.
Device Interface IP Address Subnet Mask Default Gateway
RTA Fa0/0 10.0.0.1 255.255.0.0
S0/1 10.1.160.1 255.255.255.252
S0/0 10.1.160.9 255.255.255.252
RTB Fa0/0 10.1.0.1 255.255.128.0
S0/1 10.1.160.2 255.255.255.252
S0/0 10.1.160.5 255.255.255.252
RTC Fa0/0 10.1.128.1 255.255.224.0
S0/1 10.1.160.6 255.255.255.252
S0/0 10.1.160.10 255.255.255.252
Host A 10.0.0.2 255.255.0.0 10.0.0.1
Host B 10.1.0.2 255.255.128.0 10.1.0.1
Host C 10.1.128.2 255.255.224.0 10.1.128.1
Summary Route Exercises
Use the following exercises to practice determining the summary route for a collection of subnets.
The following is an example with the answer:
Referring to Figure 1-13, what summary route would R1 send to BBR (Backbone Router) for the four networks?
Write your answer in the space provided.
Figure 1-13 Summary Route Example
192.168.1.0/27
192.168.1.32/27
192.168.1.64/27
192.168.1.96/27
Chapter 1: Introduction to Classless Routing 23
R1 BBR
Summary Route
192.168.1.0/25

24 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 1. Find the number of highest-order bits that match in all the addresses, convert the addresses to
binary format, and align them in a list.
To make sure that you are including the entire address range from the lowest to the highest network
address, find the lowest IP address, which is the network address 192.168.1.0 in the
example. Then, find the highest IP address, which is 192.168.1.127, or the last address in the
highest network, 192.168.1.96.
Write the lowest and highest IP addresses in binary:
192.168.1.0: 11000000.10101000.00000001.00000000
192.168.1.127: 11000000.10101000.00000001.01111111
Step 2. Locate where the common pattern of digits ends. The common bits are shaded in the following
example.
First IP 192.168.1.0 11000000.10101000.00000001.00000000
Last IP 192.168.1.127 11000000.10101000.00000001.01111111
Step 3. Count the number of common bits. This number is the prefix length of the summary route. It is
represented at the end of the first IP address in the block and preceded by a slash.
In this example, counting from left to right, you have 25 common bits. Your first address in the
address block is 192.168.1.0. Therefore, your summary route is 192.168.1.0/25.
Summary Route Exercise 1
Referring to Figure 1-14, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.
Figure 1-14 Summary Route Exercise 1
192.168.1.0/25
192.168.1.128/26
192.168.1.192/27
192.168.1.224/27
R1 BBR
Summary Route
192.168.1.0/24

First IP 192.168.1.0 11000000.10101000.00000001.00000000
Last IP 192.168.1.255 11000000.10101000.00000001.11111111
Summary route 192.168.1.0/24
Summary Route Exercise 2
Referring to Figure 1-15, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.
Figure 1-15 Summary Route Exercise 2
192.168.4.0/24
192.168.5.0/24
192.168.6.0/24
192.168.7.0/24
First IP 192.168.4.0 11000000.10101000.00000100.00000000
Last IP 192.168.7.255 11000000.10101000.00000111.11111111
Summary route 192.168.4.0/22
Summary Route Exercise 3
Chapter 1: Introduction to Classless Routing 25
R1 BBR
Summary Route
192.168.4.0/22
Referring to Figure 1-16, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.

26 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-16 Summary Route Exercise 3
192.168.64.0/21
192.168.72.0/21
192.168.80.0/21
192.168.88.0/21
First IP 192.168.64.0 11000000.10101000.01000000.00000000
Last IP 192.168.95.255 11000000.10101000.01011111.11111111
Summary route 192.168.64.0/19
Summary Route Exercise 4
R1 BBR
Summary Route
192.168.64.0/19
Referring to Figure 1-17, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.

Figure 1-17 Summary Route Exercise 4
172.16.0.0/14
172.20.0.0/14
172.24.0.0/14
172.28.0.0/14
First IP 172.16.0.0 10101100.00010000.00000000.00000000
Last IP 172.31.255.255 10101100.00011111.11111111.11111111
Summary route 172.16.0.0/12
Your students may be interested to know that the summary route 172.16.0.0/12 is also the entire range of
Class B private IP addresses as defined by RFC 1918.
Summary Route Exercise 5
Chapter 1: Introduction to Classless Routing 27
R1 BBR
Summary Route
172.16.0.0/12
Referring to Figure 1-18, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.

28 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-18 Summary Route Exercise 5
172.16.0.0/17
172.16.128.0/17
172.17.0.0/16
172.18.0.0/15
First IP 172.16.0.0 10101100.00010000.00000000.00000000
Last IP 172.19.255.255 10101100.00010011.11111111.11111111
Summary route 172.16.0.0/14
Summary Route Exercise 6
R1 BBR
Summary Route
172.16.0.0/14
Referring to Figure 1-19, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.

Figure 1-19 Summary Route Exercise 6
10.10.0.0/21
10.10.8.0/21
10.10.16.0/21
10.10.24.0/21
First IP 10.10.0.0 00001010.00001010.00000000.00000000
Last IP 10.10.31.255 00001010.00001010.00011111.11111111
Summary route 10.10.0.0/19
Summary Route Exercise 7
Referring to Figure 1-20, what summary route would R1 send to BBR for the four networks? Write your
answer in the space provided.
Figure 1-20 Summary Route Exercise 7
10.0.0.0/16
10.1.0.0/16
10.2.0.0/15
10.4.0.0/14
Chapter 1: Introduction to Classless Routing 29
R1 BBR
Summary Route
10.10.0.0/19
R1 BBR
Summary Route
10.0.0.0/13

30 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
First IP 10.0.0.0 00001010.00000000.00000000.00000000
Last IP 10.7.255.255 00001010.00000111.11111111.11111111
Summary route 10.0.0.0/13
Default and Static Routing Scenario
In Figure 1-21, both static and default routing are used between RTA and ISP to route traffic. First, determine
the summary route that would summarize all of the subnets from the 10.0.0.0 address space. Then,
record the commands that would be configured on RTA and ISP to provide full connectivity. (Hint: RTA
will use a default route and ISP will use a static route.)
Figure 1-21 Default and Static Routing Scenario
10.10.1.224/28
To find the summary route, find the common bits shared by the first and last addresses in the address
space.
First IP 10.10.1.128 00001010.00001010.00000001.10000000
Last IP 10.10.1.255 00001010.00001010.00000001.11111111
Summary route 10.10.1.128/25
10.10.1.128/26
RTA
RTC 10.10.1.244/30
RTB
Now configure ISP with a static route pointing to the summary of the address space:
ISP(config)#ip route 10.10.1.128 255.255.255.128 209.165.201.2
S1/0
209.165.201.2/30
10.10.1.248/30 10.10.1.240/30
RTA will use a default route to ISP because ISP provides connectivity to destinations outside the
10.10.1.128/25 address space:
RTA(config)#ip route 0.0.0.0 0.0.0.0 209.165.201.1
209.165.201.1/30
S0/0
DCE
10.10.1.192/27
ISP

Concept Questions
List at least three reasons why you should use VLSM when designing your addressing scheme.
■ More efficient use of IP addresses
■ Greater capability to use route summarization
■ Isolation of topology changes from other routers
Why is VLSM described as “subnetting a subnet”?
From the instructor version of the curriculum:
VLSM is often referred to as “subnetting a subnet” because any network address space—whether a classful
address like 192.168.1.0/24 or a classless address like 192.168.1.32/27—can be further subnetted to
provide another level of logical addressing.
Why was VLSM not used in CCNA 1 and CCNA 2?
From the instructor version of the curriculum:
There are two main reasons why VLSM is not used in CCNA 1 and CCNA 2:
■ Historically, subnetting has proved to be one of the more challenging skills students must master during
the first two CCNA courses. Adding the concept of VLSM to this already difficult task is unnecessary,
namely because….
■ CCNA 2 only deals with classful routing. Students do not yet implement classless addressing schemes
in their network designs.
What is the difference between CIDR and supernetting or router summarization?
From the instructor version of the curriculum:
Classless Interdomain Routing (CIDR) is the mechanism that allows advertising of both supernets and subnets
outside of the normal bounds of a classful network number. Supernetting is a representation that
allows masks that are shorter than the natural masks, therefore creating supernets.
From Switching Basics and Intermediate Routing CCNA 3 Companion Guide, by Wayne Lewis (Cisco
Networking Academy Program):
Although there is no consensus, the term route summarization often applies to summarizing within a classful
boundary; on the other hand, CIDR almost always refers to combining several classful networks. With
both CIDR and route summarization, the point is to optimize routing. To illustrate the difference between
route summarization and CIDR, a network engineer may define a summary route on a Cisco router for a
company’s network, but this has nothing to do with allocating a block of addresses to a customer.
List the two ways a router running a classful routing protocol can calculate the network portion of routes
received in routing updates.
From Switching Basics and Intermediate Routing CCNA 3 Companion Guide:
■ If the routing update information contains the same major network number as configured on the
receiving interface, the router applies the subnet mask that is configured on the receiving interface.
■ If the routing update information contains a different major network than the one configured on the
receiving interface, the router applies the default classful mask by IP address class.
Explain three ways a router can learn paths to destination networks.
From Switching Basics and Intermediate Routing CCNA 3 Companion Guide:
Chapter 1: Introduction to Classless Routing 31
■ Static routes are manually defined by the system administrator via an attached interface or the next
hop to a destination. These are useful for security and reducing routing traffic.

32 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
■ Default routes are also manually defined by the network engineer as the path to take when no known
route exists to the destination. Default routes are essential to minimizing the size of a routing table.
When an entry for a destination network does not exist in a routing table, the packet is sent via the
route.
■ Dynamic routing is where the router learns of paths to destinations by receiving routing updates from
other routers via a routing protocol such as RIP.
Explain the effect of the command ip classless on both classful and classless routing protocols.
From Switching Basics and Intermediate Routing CCNA 3 Companion Guide:
The ip classless command causes a classful routing protocol to evaluate all packets using the longestmatch
criterion. Instead of discarding traffic bound for unknown subnets of a known classful network, a
router tries to match the largest number of bits possible against the route in its routing table.
Note that ip classless has no effect on routers running classless routing protocols, because they already use
the longest-match criterion in making routing decisions.
List the two classful routing protocols and explain the most serious limitation of these two protocols.
RIPv1 and IGRP are both classful routing protocols. Neither RIPv1 nor IGRP sends subnet mask information
in routing updates. Therefore, subnets must use the same mask and must be assigned contiguously.
Not only does this waste address space, but classful routing is not very scalable. Adding a new subnet
between two contiguously addressed subnets will necessitate designing a new addressing scheme.
Which classless routing protocols automatically summarize at the classful boundary? Why do these protocols
operate in a classful manner? What command will turn off automatic summarization and with which
IOS versions must you enter the command?
By default RIPv2, EIGRP, and BGP all summarize at the classful boundary. Automatic summarization
enables RIPv2 and EIGRP to be backward compatible with their predecessors, RIPv1 and IGRP. In situations
in which you want to manually summarize routes at a different bit boundary or want to be able to
assign subnets discontiguously, turn off automatic summarization with the no auto-summary command.
With Cisco IOS Release 12.2(8)T, EIGRP and BGP have auto-summary disabled by default; prior to
12.2(8)T, EIGRP and BGP had auto-summary enabled by default. With RIPv2, auto-summary has
always been and remains enabled by default.
VLSM Case Study
You are the new network administrator for Mom and Pop’s Stop & Shop, a multibranch convenience store
corporation. The previous network administrator used the 192.168.1.0/24 private network exclusively to
communicate between branch locations and corporate headquarters. The current topology and addressing
scheme is shown in Figure 1-22.
Mom and Pop’s Stop & Shop plans to add two new locations this year. With the current addressing
scheme, how many subnets are left to provide address space for the new locations? As the new network
administrator, what plan would you have for adding additional address space when needed? What routing
protocol would you use?

Figure 1-22 Mom and Pop’s Stop & Shop Network Topology
172.16.7.0/24
192.168.1.192/28
172.16.8.0/24
Store8
Store7 HQ 192.168.1.80/28 Store3
192.168.1.176/28
Store6
172.16.6.0/24
172.16.0.20/30
172.16.0.28/30
172.16.0.24/30
172.16.0.16/30
192.168.1.144/28
172.16.1.0/24
The current addressing scheme only allows for an additional four subnets: 192.168.1.0/28,
192.168.1.208/28, 192.168.1.224/28, and 192.168.240/28. This is enough for the current needs. However,
no more subnets will be available for future expansion. In addition, the current design is wasting
12 addresses on each WAN link. A better solution would be to implement VLSM and a classless
routing protocol.
Allow students to design their own addressing scheme to reinforce the VLSM concepts learned in this
chapter. This will provide you with several examples to compare and contrast. Discuss with the students as
a class the benefits and drawbacks of different solutions.
The following is a sample solution using the 172.16.0.0/16 address space:
Chapter 1: Introduction to Classless Routing 33
192.168.1.32/28
Store1
172.16.0.0/30
192.168.1.16/28
192.168.1.112/28
Store5
192.168.1.160/28
172.16.5.0/24
172.16.0.8/30
172.16.0.12/30
172.16.2.0/24
Store2
192.168.1.48/28
172.16.0.4/30
Store4
172.16.4.0/24
192.168.1.64/28
172.16.3.0/24
192.168.1.96/28
192.168.1.128/28
Although the current stores need only a handful of IP addresses, future needs are always more demanding.
To provide enough address space for any possible future needs at each store, give each store a /24 subnet.
WAN links will be assigned exclusively from the 172.16.0.0/24 address space. (You just as easily could
have used the last /24 subnet or 172.16.255.0/24.) Store subnets will match the store numbers already used
by Mom and Pop’s. The addressing convention will be 172.16.x.0/24, where x is the store number. Using a
numbering scheme that also denotes the location helps tremendously when troubleshooting. For example, a
poorly performing or failing NIC can cause a flood of meaningless traffic. This traffic can be identified by
its IP address using network monitoring software. The IP address alone is enough to tell you which store is
generating the excess traffic.
For routing, you can use any classless routing protocol, including RIPv2, OSPF, and EIGRP. However,
although the network is large, it is not overly complex. There is no need to complicate the situation with a
more complex routing protocol. RIPv2 is probably the best choice in this situation.

34 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
RIP Version 2
RIP was designed to work as a simple Interior Gateway Protocol (IGP) within small and moderate-sized
autonomous systems. The first version of RIP did not support VLSM, but rather simply advertised the
classful network to RIP neighbors. However, the original RIP specification (RFC 1058) provided several
empty fields in the RIP update that are now used by RIP version 2 (RFC 2453). In the following two exercises,
you will compare and contrast RIPv1 and RIPv2. Then, you will complete a research exercise to discover
more details about the two versions of RIP.
Compare and Contrast Exercise
Compare and contrast RIPv1 and RIPv2 by listing the features of each protocol in the following table.
RIPv1 Features RIPv2 Features
Hop count is the metric. Hop count is the metric.
Maximum hop count is 15. Maximum hop count is 15.
Uses hold-down timers to prevent routing loops. Uses hold-down timers to prevent routing loops.
Uses split-horizon to prevent routing loops. Uses split-horizon to prevent routing loops.
Failure to receive updates in a timely manner Failure to receive updates in a timely manner results in
results in removal of routes previously learned removal of routes previously learned from a neighbor.
from a neighbor.
The administrative distance is 120. The administrative distance is 120.
Routing updates are broadcast every Routing updates are multicast every 30 seconds by 30
seconds by default. default.
Capable of load balancing over as many as six Capable of load balancing over as many as six
equal-cost paths—four paths by default. equal-cost paths—four paths by default.
Authentication is not supported. Supports clear-text and Message Digest 5 (MD5)
authentication.
VLSM is not supported— VLSM is supported—sends mask in the update.
it is a classful routing protocol.
Does not support manual route summarization. Supports manual route summarization.
From your preceding list of features, what are the four improvements added to RIPv2?
■ Multicasting of updates
■ Support for simple and MD5 authentication
■ Support for VLS because subnet mask information is sent in updates
■ Support for route summarization
Internet Research
RIP is an open standard, which means the specifications for the format of RIP messages is not proprietary
and can be implemented by any vendor or software developer. When you are not sure about an open standard
such as RIP or OSPF, you can always refer to the original Request For Comments (RFC) for that
standard. For this research exercise, use the Internet to find the RFC for RIPv2 and answer the following
questions.

Students should be well versed in using search tools. The RFCs for RIPv1 and RIPv2 exist is several
places on the Internet. Emphasize that they should look for the most recent version of the RFC. In this
case, RFC 2453 is sufficient to answer all of the following questions. Students should also be encouraged
to find the original source for RFCs—the Internet Engineering Task Force (IETF). According to
http://www.ietf.org, IETF “…is a large open international community of network designers, operators,
vendors, and researchers concerned with the evolution of the Internet architecture and the smooth operation
of the Internet.” The IETF collection of RFCs can be found at http://www.ietf.org/rfc/rfc#, where # is
the number of the RFC.
What Layer 4 protocol does RIP use and what is its port number?
RIP used UDP and its port number is 520.
How many routing updates can a RIP update contain?
A RIP update can contain up to 25 routing updates.
RIPv1 and RIPv2 both use the same header information. RIPv2 uses empty fields in the 20-byte RIPv1
route entry. Fill in the names of the fields for both the RIPv1 and RIPv2 route entries in Figure 1-23 and
Figure 1-24, respectively. (Hint: Look for phrases “message format” and “protocol extensions.”)
Figure 1-23 RIPv1 Header and Route Entry
Command (1)
Address Family Identifier (2)
IPv4 Address (4)
Chapter 1: Introduction to Classless Routing 35
Version (1) Must be Zero (2)
Must be Zero (4)
Must be Zero (4)
Metric (4)
Must be Zero (4)

36 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-24 RIPv2 Header and Route Entry
Command (1) Version (1) Must be Zero (2)
Address Family Identifier (2)
IPv4 Address (4)
Subnet Mask (4)
Next Hop (4)
Metric (4)
Notice that authentication is not listed in any of the fields. Briefly explain how RIPv2 allows authentication
of messages.
From RFC 2453:
Since authentication is a per message function, and since there is only one 2-octet field available in the
message header, and since any reasonable authentication scheme will require more than two octets, the
authentication scheme for RIP version 2 will use the space of an entire RIP entry. If the Address Family
Identifier of the first (and only the first) entry in the message is 0xFFFF, then the remainder of the entry
contains the authentication. This means that there can be, at most, 24 RIP entries in the remainder of the
message. If authentication is not in use, then no entries in the message should have an Address Family
Identifier of 0xFFFF.
Briefly explain the use of the fields Route Tag and Next Hop.
Route Tag (2)
From RFC 2453:
4.2 Route Tag
The intended use of the Route Tag is to provide a method of separating “internal” RIP routes (routes for
networks within the RIP routing domain) from “external” RIP routes, which may have been imported from
an EGP or another IGP.
4.4 Next Hop
The immediate next hop IP address to which packets to the destination specified by this route entry should
be forwarded. Specifying a value of 0.0.0.0 in this field indicates that routing should be via the originator
of the RIP advertisement.

Lab Exercises
Command Reference
In the table that follows, record the command, including the correct router prompt, that fits the description.
Command Description
Router(conig)#ip classless Causes a classful routing protocol to evaluate all packets
using the longest-match criterion. As a last resort, the
router will use the default route rather than discard
traffic bound for unknown subnets of a known classful
network.
Router(config)#ip subnet-zero Allows the use of the all-0 subnets; on by default in
Cisco IOS Software Release 12.0 and later.
Router(config)#router rip Turns off the RIP routing process.
Router(config-router)#version 2 Turns on Version 2 of the routing process.
Router(config-router)#network a.b.c.d Configures the network number of the directly connect
ed classful network you want to advertise.
Router(config-router)#no auto-summary RIPv2 summarizes networks at the classful boundary.
This command turns off autosummarization.
Router#debug ip rip Displays all RIP activity in real time.
Router#show ip rip database Displays contents of the RIP database.
Curriculum Lab 1-1: Calculating VLSM Subnets (1.1.4)
Figure 1-25 Topology for Lab 1-1
192.168.10.128/30
Address Space
192.168.10.0/24
Perth
KL
Sydney
Chapter 1: Introduction to Classless Routing 37
28 Hosts
192.168.10.64/27
192.168.10.132/30 192.168.10.136/30
Singapore
60 Hosts
12 Hosts
12 Hosts
192.168.10.0/26 192.168.10.96/28 192.168.10.112/28

38 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Objective
Use variable-length subnet masking (VLSM) to support more efficient use of the assigned IP address and
to reduce the amount of routing information at the top level.
The solution to this VLSM lab is provided in the steps themselves. Students should take the recommended
subnetting in each step and build a diagram of the network, showing routers, LANs, and WAN links. Each
LAN and WAN link should be labeled with the appropriate subnet address and slash number. A suggested
diagram can be found at the end of this lab.
Background/Preparation
A Class C address of 192.168.10.0/24 has been allocated.
Perth, Sydney, and Singapore have a WAN connection to Kuala Lumpur. The host requirements are
as follows:
■ Perth requires 60 hosts.
■ Kuala Lumpur requires 28 hosts.
■ Sydney and Singapore each require 12 hosts.
To calculate VLSM subnets and the respective hosts, allocate the largest requirements first from the
address range. Requirements levels should be listed from the largest to the smallest.
In this example, Perth requires 60 hosts. Use 6 bits, because 2 6 – 2 = 62 usable host addresses. Thus,
2 bits will be used from the fourth octet to represent the extended network prefix of /26, and the remaining
6 bits will be used for host addresses.
Task 1: Divide the Allocated Addresses into Four Equal-Sized
Address Blocks
Step 1. Divide the allocated address of 192.168.10.0/24 into four equal-sized address blocks. Because
4 = 2 2 , 2 bits are required to identify each of the four subnets.
Step 2. Take subnet 0 (192.168.10.0/26) and identify each of its hosts. Table 1-1 documents the allocated
addresses, subnetworks, and usable hosts.
Table 1-1 Usable Hosts for 192.168.10.0/24
Allocated Address Subnetworks 62 Usable Hosts/Subnetworks (Subnet 0)
192.168.10.0/24 192.168.10.0/26 192.168.10.0/26 (network address)
Table 1-2 lists the range for the /26 mask.
192.168.10.64/26 192.168.10.1/26
192.168.10.128/26 192.168.10.2/26
192.168.10.192/26 192.168.10.3/26
through
192.168.10.61/26
192.168.10.62/26
192.168.10.63/26 (broadcast address)

Table 1-2 IP Address Range for 192.168.10.0/26
Perth Range of Addresses in the Last Octet
192.168.10.0/26 From 0 to 63. Sixty hosts required.
Hosts 0 and 63 cannot be used because they are the network and broadcast
addresses for their subnet.
Task 2: Allocate the Next Level After All the Requirements Are
Met for the Higher Level(s)
Kuala Lumpur requires 28 hosts. The next available address after 192.168.10.63/26 is 192.168.10.64/26.
Note from Table 1-2 that this is subnet 1. Because 28 hosts are required, 2 5 – 2 = 30 usable network
addresses. Thus, 5 bits will be required to represent the hosts, and 3 bits will be used to represent the
extended network prefix of /27. Applying VLSM on address 192.168.10.64/27 gives the results in Table 1-3.
Table 1-3 Usable Hosts for 192.168.10.64/26
Subnetwork 1 Sub-Subnetworks 30 Usable Hosts
192.168.10.64/26 192.168.10.64/27 192.168.10.65/27
Table 1-4 lists the range for the /27 mask.
192.168.10.96/27 192.168.10.66/27
192.168.10.128/27 192.168.10.67/26
192.168.10.192/27 through
Table 1-4 IP Address Range for 192.168.10.64/27
Kuala Lumpur Range of Addresses in the Last Octet
192.168.10.64/27 (network address)
192.168.10.93/27
192.168.10.94/27
192.168.10.95/27 (broadcast address)
192.168.10.64/27 From 64 to 95. 28 hosts required.
Hosts 64 and 95 cannot be used because they are the network and broadcast
addresses for their subnet. Thirty usable addresses are available in this range for
the hosts.
Task 3: Allocate Address Space for Sydney
Chapter 1: Introduction to Classless Routing 39
Sydney and Singapore require 12 hosts each. The next available address starts from 192.168.10.96/27.
Note from Table 1-2 that this is the next subnet available. Because 12 hosts are required, 2 4 – 2 = 14
usable addresses. Thus, 4 bits are required to represent the hosts, and 4 bits are required for the extended
network prefix of /28. Applying VLSM on address 192.168.10.96/27 gives the results in Table 1-5.

40 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 1-5 Usable Hosts for 192.168.10.96/27
Subnetwork 2 Sub-Subnetworks 14 Usable Hosts
192.168.10.96/27 192.168.10.96/28 192.168.10.96/28 (network address)
Table 1-6 lists the range for the /28 mask.
192.168.10.112/28 192.168.10.97/28
192.168.10.128/28 192.168.10.98/28
192.168.10.224/28 192.168.10.99/28
192.168.10.240/28 through
Table 1-6 IP Address Range for 192.168.10.96/28
Sydney Range of Addresses in the Last Octet
192.168.10.109/28
192.168.10.110/28
192.168.10.111/28 (broadcast address)
192.168.10.96/28 From 96 to 111. Twelve hosts required.
Hosts 96 and 111 cannot be used because they are network and broadcast
addresses for their subnet. Fourteen usable addresses are available in this range
for the hosts.
Task 4: Allocate Address Space for Singapore
Because Singapore also requires 12 hosts, the next set of host addresses in Table 1-7 can be derived from
the next available subnet (192.168.10.112/28).
Table 1-7 Singapore Host Addresses
Sub-Subnetworks 14 Usable Hosts
192.168.10.96/28 192.168.10.112/28 (network address)
192.168.10.112/28 192.168.10.113/28
192.168.10.128/28 192.168.10.114/28
192.168.10.224/28 192.168.10.115/28
through
192.168.10.240/28 192.168.10.125/28
Table 1-8 lists the range for the /28 mask.
192.168.10.126/28
192.168.10.127/28 (broadcast address)

Table 1-8 IP Address Range for 192.168.10.112/28
Singapore Range of Addresses in the Last Octet
192.168.10.112/28 From 112 to 127. Twelve hosts required.
Hosts 112 and 127 cannot be used because they are network and broadcast
addresses for their subnet. Fourteen usable addresses are available in this
range for the hosts.
Task 5: Allocate Address Space for WAN Links
Now allocate addresses for the WAN links. Remember that each WAN link requires two IP addresses. The
next available subnet is 192.168.10.128/28. Because two network addresses are required for each WAN
link, 2 2 – 2 = 2 usable addresses. Thus, 2 bits are required to represent the links, and 6 bits are required
for the extended network prefix of /30. Applying VLSM on 192.168.10.128/28 gives the results in Table 1-9.
Table 1-9 Usable Hosts After Applying VLSM on 192.168.10.112/28
Sub-Subnetworks 14 Usable Hosts
192.168.10.128/30 192.168.10.128/30 (network address)
192.168.10.129/30
192.168.10.130/30
192.168.10.31/30 (broadcast address)
192.168.10.132/30 192.168.10.132/30 (network address)
192.168.10.133/30
192.168.10.134/30
192.168.10.135/30 (broadcast address)
192.168.10.136/30 192.168.10.136/30 (network address)
192.168.10.137/30
192.168.10.138/30
192.168.10.139/30 (broadcast address)
Chapter 1: Introduction to Classless Routing 41
The available addresses for the WAN links can be taken from the available addresses in each of the /30
subnets.
Sometimes, a visual will help your students see how an address space can be used with VLSM. One visual
I like to use is to represent the address space in a big, square box, as shown in Figure 1-25B.

42 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-25B VLSM Design Using a Visual
This diagram illustrates how the
Class C address was subnetted
using VLSM. The network address
and broadcast address for
each subnet are shown in the
corners of each box.
0
64
/27
95
/26
96
112
128
/30
131
132
/30
135
144
First, draw a large box on the board. Label the top-left corner with the subnet address and the bottom-right
corner with the broadcast address. For our beginning address space in this lab, the corners are .0 and .255,
respectively.
For the first VLSM step, we borrowed 2 bits. This can be represented visually by bisecting the box in half
two times (for 2 bits). First, draw a horizontal line cutting the box in half. Then, draw a vertical line cutting
the box into fourths. This visually represents to your students that we created four subnets. Now label
each box’s top-left and bottom-right corners with the beginning and ending address in each of the subnets.
So, the top-left box already has .0 but needs an address for the bottom left, which is the broadcast address
for that subnet or .63. You can see from Figure 1-25B how the other four boxes are labeled.
In the lab, we assigned the first box to Perth because 192.168.10.0/26 is enough address space for
60 hosts. In our figure, we can label the box with “Perth LAN /26” so that we know that block of
addresses has been assigned.
/28
/28
63
192
Next, we need address space for the 28 hosts attached to Kuala Lumpur. So, we subnet the .64/26 address
space borrowing 1 bit. In our visual, we draw a vertical line bisecting this block of addresses and label our
corners. Then, we assign 192.168.10.64/27 to Kuala Lumpur’s LAN.
Sydney and Singapore both need address space to support 12 hosts. Continuing contiguously through our
address space, we borrow 1 bit from the 192.168.10.96/27 address space to make two subnets:
192.168.10.96/28 and 192.168.10.112/28. In our visual, we draw a horizontal line to represent the borrowing
of 1 bit and label each box with the name of the LAN assigned to that block of addresses.
Our last step is to assign WAN links. We have the entire second half of the address space available represented
by 192.168.10.128/25. For WAN links, we need only two hosts. Therefore, we can borrow 5 more
bits from 192.168.10.128/25. In our visual, we represent the 5 bits borrowed by first drawing a horizontal
line to bisect the 192.168.10.128/25 address space. Then, we draw a vertical line in the upper box to bisect
the 192.168.10.128/26 address space. Then, we draw a third line to bisect the 192.168.10.128/27 address
space. Finally, we draw a vertical line and a horizontal line to bisect the 192.168.10.128/28 address space
into four subnets perfect for WAN links.
111
127
136
/30
139
140
/30
143
159
160
191
255

To finish our visual, we label all the corners and designate what the prefix is for each address space. These
are our leftover, unused subnets.
Remember, not every student will care for the visual way of representing VLSM. Many prefer to simply
do it by hand. In addition, this visual method can be difficult with larger address spaces. Imagine trying to
do this same exercise with a 10.0.0.0/8 address space and eight levels of subnetting. It would not be
impossible, but it also would not be very effective. However, I have found that, for some students, the
“light comes on” when I use a visual representation for VLSM.
Curriculum Lab 1-2: Review of Basic Router Configuration
with RIP (1.2.3)
Figure 1-26 Topology for Lab 1-2
Straight-Through Cable
Table 1-10 Lab Equipment Configuration
Router Router Name Fast Ethernet 0 Address Interface Type Serial 0 Address
Designation
Router 1 GAD 172.16.0.1 DCE 172.17.0.1
Router 2 BHM 172.18.0.1 DTE 172.17.0.2
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both interfaces on both routers is 255.255.0.0.
Chapter 1: Introduction to Classless Routing 43
Router 1 Router 2
Rollover (Console) Cable
Crossover Cable
Serial Cable

44 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Objectives
■ Cable and configure workstations and routers.
■ Set up an IP addressing scheme by using Class B networks.
■ Configure RIP on routers.
Background/Preparation
Cable a network that is similar to the one in Figure 1-26. You can use any router that meets the interface
requirements in Figure 1-26 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A, “Router Interface Summary Chart,” to correctly specify the interface identifiers
based on the equipment in your lab. The 1721 series routers produced the configuration output in
this lab. Another router might produce slightly different output. You should execute the following steps on
each router unless you are specifically instructed otherwise.
Implement the procedure documented in Appendix C, “Erasing and Reloading the Router,” before you
continue with this lab.
General Configuration Tips
■ Use the question mark (?) and arrow keys to help to enter commands.
■ Each command mode restricts the set of available commands. If you have difficulty entering a command,
check the prompt and then enter ? for a list of available commands. The problem might be a
wrong command mode or wrong syntax.
■ To disable a feature, enter the keyword no before the command; for example, no ip routing.
■ Save the configuration changes to nonvolatile RAM (NVRAM) so that the changes are not lost if there
is a system reload or power outage.
Table 1-11 lists the router command modes for this and other labs in the chapter.
Table 1-11 Router Command Modes
Command Mode Access Method Router Prompt Exit Method
Displayed
User EXEC Log in. Router> Use the logout command.
Privileged EXEC From user EXEC Router# To exit to user EXEC mode,
mode, enter the use the disable, exit, or
enable command. logout command.
Global From privileged EXEC Router(config)# To exit to privileged EXEC
configuration mode, enter the mode, use the exit or end
configure terminal command, or press Ctrl-Z.
command.
Interface From global Router(config-if)# To exit to global configuraconfiguration
configuration mode, tion mode, use the exit
enter the interface command.
type number command,
such as interface serial 0.

Task 1: Basic Router Configuration
Connect one end of a rollover cable to the console port on the router and connect the other end to the PC
with a DB-9 or DB-25 adapter to a COM port. You should do this prior to powering on any devices.
Task 2: Start the HyperTerminal Program
Step 1. Turn on the computer and router.
Step 2. From the Windows taskbar, locate the HyperTerminal program by choosing Start > Programs
> Accessories > Communications > HyperTerminal.
Task 3: Name the HyperTerminal Session
In the Connection Description dialog box, enter a name in the Name field and click OK (see Figure 1-27).
Figure 1-27 HyperTerminal Connection Description Dialog Box
Chapter 1: Introduction to Classless Routing 45
Task 4: Specify the Computer’s Connecting Interface
In the Connect To dialog box, select COM1 from the Connect Using drop-down list and click OK (see
Figure 1-28).

46 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 1-28 HyperTerminal Connect To Dialog Box
Task 5: Specify the Interface Connection Properties
Step 1. In the COM1 Properties dialog box, use the drop-down arrows to select the following (see
Figure 1-29):
Bits per second = 9600
Data bits = 8
Parity = None
Stop bits = 1
Flow control = None
Step 2. Click OK.

Figure 1-29 HyperTerminal Interface Connection Property Settings
Step 3. When the HyperTerminal session window opens (see Figure 1-30), turn on the router. If the
router is already on, press the Enter key. The router should respond.
Figure 1-30 HyperTerminal Session Window
If the router responds, the connection has been successfully completed.
Chapter 1: Introduction to Classless Routing 47

48 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 6: Close the Session
Step 1. To end the console session from a HyperTerminal session, choose File > Exit.
Step 2. When the HyperTerminal disconnect warning dialog box appears, click Yes (see Figure 1-31).
Figure 1-31 Closing a HyperTerminal Session
Step 3. The computer asks if you want to save the session (see Figure 1-32). Click Yes.
Figure 1-32 Saving a HyperTerminal Session
Task 7: Reopen the HyperTerminal Connection
Step 1. In the Connection Description dialog box (refer to Figure 1-27), click Cancel.
Step 2. To open the saved console session from HyperTerminal, choose File > Open. The saved session
will appear. By double-clicking on the name, the connection opens without reconfiguring
it each time.

Task 8: Configure Hostname and Passwords on Router GAD
Enter enable at the user mode prompt and enter the rest of the commands in the following code.
Router>enable
Router#configure terminal
Router(config)#hostname GAD
GAD(config)#enable password cisco
GAD(config)#enable secret class
GAD(config)#line console 0
GAD(config-line)#password cisco
GAD(config-line)#login
GAD(config-line)#line vty 0 4
GAD(config-line)#password cisco
GAD(config-line)#login
GAD(config-line)#exit
GAD(config)#
Task 9: Configure Interface Serial 0 on Router GAD
From global configuration mode, configure interface serial 0 (refer to Appendix A) on router GAD.
GAD(config)#interface serial 0
GAD(config-if)#ip address 172.17.0.1 255.255.0.0
GAD(config-if)#clock rate 64000
GAD(config-if)#no shutdown
GAD(config-if)#exit
Task 10: Configure the Fast Ethernet 0 Interface on Router GAD
GAD(config)#interface fastethernet 0
GAD(config-if)#ip address 172.16.0.1 255.255.0.0
GAD(config-if)#no shutdown
GAD(config-if)#exit
Task 11: Configure the IP Host Statements on Router GAD
GAD(config)#ip host BMH 172.18.0.1 172.17.0.1
Chapter 1: Introduction to Classless Routing 49

50 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 12: Configure RIP Routing on Router GAD
GAD(config)#router rip
GAD(config-router)#network 172.16.0.0
GAD(config-router)#network 172.17.0.0
GAD(config-router)#exit
GAD(config)#exit
Task 13: Save the GAD Router Configuration
GAD#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Task 14: Configure Hostname and Passwords on Router BHM
Enter enable at the user mode prompt and enter the rest of the commands in the following code.
Router>enable
Router#configure terminal
Router(config)#hostname BHM
BHM(config)#enable password cisco
BHM(config)#enable secret class
BHM(config)#line console 0
BHM(config-line)#password cisco
BHM(config-line)#login
BHM(config-line)#line vty 0 4
BHM(config-line)#password cisco
BHM(config-line)#login
BHM(config-line)#exit
BHM(config)#
Task 15: Configure Interface Serial 0 on Router BHM
From global configuration mode, configure interface serial 0 (refer to Appendix A) on router BHM.
BHM(config)#interface serial 0
BHM(config-if)#ip address 172.17.0.2 255.255.0.0
BHM(config-if)#no shutdown
BHM(config-if)#exit
Task 16: Configure the Fast Ethernet 0 Interface on Router BHM
BHM(config)#interface fastethernet 0
BHM(config-if)#ip address 172.18.0.1 255.255.0.0
BHM(config-if)#no shutdown
BHM(config-if)#exit

Task 17: Configure the IP Host Statements on Router BHM
BHM(config)#ip host GAD 172.16.0.1 172.17.0.1
Task 18: Configure RIP Routing on Router BHM
BHM(config)#router rip
BHM(config-router)#network 172.18.0.0
BHM(config-router)#network 172.17.0.0
BHM(config-router)#exit
BHM(config)#exit
Task 19: Save the BHM Router Configuration
BHM# copy running-config startup-config
Destination filename [startup-config]?[Enter]
Task 20: Configure the Hosts
Using the following information, configure the hosts with the proper IP address, subnet mask, and default
gateway:
Host connected to router GAD
IP address: 172.16.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.16.0.1
Host connected to router BHM
IP address: 172.18.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.18.0.1
Chapter 1: Introduction to Classless Routing 51
Task 21: Verify the Internetwork Is Functioning by Pinging the
Fast Ethernet Interface of the Other Router
Step 1. From the host that is attached to GAD, ping the BHM router Fast Ethernet interface. Was the
ping successful? Yes
Step 2. From the host that is attached to BHM, ping the GAD router Fast Ethernet interface. Was the
ping successful? Yes
Step 3. If the answer is no for either question, troubleshoot the router configurations to find the error.
Then, do the pings again until the answer to both questions is yes. Finally, ping all interfaces in
the network.

52 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 22: Show the Routing Tables for Each Router
Step 1. From enable (privileged EXEC) mode, examine the routing table entries by using the show ip
route command on each router.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate
default
route
U - per-user static route, o - ODR, P - periodic downloaded static
T - traffic engineered route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.16.0.0/16 is directly connected, FastEthernet0
R 172.18.0.0/16 [120/1] via 172.17.0.2, Serial0
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area * - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
R 172.16.0.0/16 [120/1] via 172.17.0.1, 00:00:27, Serial0
C 172.18.0.0/16 is directly connected, FastEthernet0
What are the entries in the GAD routing table?
Networks 172.17.0.0/16 and 172.16.0.0/16 are directly connected and network 172.18.0.0/16
was learned through RIP from next hop 172.17.0.2 through local interface serial 0.
What are the entries in the BHM routing table?
Networks 172.17.0.0/16 and 172.18.0.0/16 are directly connected and network 172.16.0.0/16
was learned through RIP from next hop 172.17.0.1 through local interface serial 0.
Step 2. Upon completion of the previous step, log off (by typing exit) and turn the router off. Then,
remove and store the cables and adapter.

Curriculum Lab 1-3: Converting RIPv1 to RIPv2 (1.2.4)
Figure 1-33 Topology for Lab 1-3
Table 1-12 Lab Equipment Configuration
Router Router Name Fast Ethernet 0 Address Interface Type Serial 0 Address
Designation
Router 1 GAD 172.16.0.1 DCE 172.17.0.1
Router 2 BHM 172.18.0.1 DTE 172.17.0.2
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both interfaces on both routers is 255.255.0.0.
Objectives
■ Configure RIP Version 1 on routers.
■ Convert to RIP Version 2 on routers.
Background/Preparation
Straight-Through Cable
Chapter 1: Introduction to Classless Routing 53
Router 1 Router 2
Rollover (Console) Cable
Crossover Cable
Serial Cable
Cable a network similar to the one in Figure 1-33. You can use any router that meets the interface requirements
in Figure 1-33 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to the
information in Appendix A to correctly specify the interface identifiers based on the equipment in your lab.
The 1721 series routers produced the configuration output in this lab. Another router might produce slightly
different output. You should execute the following steps on each router unless you are specifically
instructed otherwise.

54 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, configure the hostnames, console, virtual terminal, and enable passwords. Next, configure
the serial (IP address and clock rate) and Fast Ethernet (IP address) interfaces. Finally, configure IP hostnames.
If you have problems performing the basic configuration, refer to Lab 1-2, “Review of Basic
Router Configuration with RIP.” You can also configure optional interface descriptions and message of the
day banners. Be sure to save the configurations you just created.
Router 1
Router>enable
Router#configure terminal
Router(config)#hostname GAD
GAD(config)#enable secret class
GAD(config)#line console 0
GAD(config-line)#password cisco
GAD(config-line)#login
GAD(config-line)#line vty 0 4
GAD(config-line)#password cisco
GAD(config-line)#login
GAD(config-line)#exit
GAD(config)#interface serial 0
GAD(config-if)#ip address 172.17.0.1 255.255.0.0
GAD(config-if)#clock rate 64000
GAD(config-if)#no shutdown
GAD(config-if)#exit
GAD(config)#interface Fastethernet 0
GAD(config-if)#ip address 172.16.0.1 255.255.0.0
GAD(config-if)#no shutdown
GAD(config-if)#exit
GAD(config)#ip host BMH 172.18.0.1 172.17.0.2
Router 2
Router>enable
Router#configure terminal
Router(config)#hostname BHM
BHM(config)#enable secret class
BHM(config)#line console 0
BHM(config-line)#password cisco
BHM(config-line)#login
BHM(config-line)#line vty 0 4
BHM(config-line)#password cisco
BHM(config-line)#login
BHM(config-line)#exit

BHM(config)#interface serial 0
BHM(config-if)#ip address 172.17.0.2 255.255.0.0
BHM(config-if)#no shutdown
BHM(config-if)#exit
BHM(config)#interface Fastethernet 0
BHM(config-if)#ip address 172.18.0.1 255.255.0.0
BHM(config-if)#no shutdown
BHM(config-if)#exit
BHM(config)#ip host GAD 172.16.0.1 172.17.0.1
Task 2: Configure the Routing Protocol on Router GAD
Go to the proper command mode and configure RIP routing on the GAD router according to Table 1-12.
GAD(config)#router rip
GAD(config-router)#network 172.16.0.0
GAD(config-router)#network 172.17.0.0
GAD(config-router)#exit
GAD(config)#exit
Task 3: Save the GAD Router Configuration
Any time that changes are correctly made to the running configuration, you should save them to the startup
configuration. Otherwise, if the router is reloaded or power cycled, the changes that are not in the startup
configuration are lost.
GAD#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Task 4: Configure the Routing Protocol on Router BHM
Go to the proper command mode and configure RIP routing on the BHM router according to Table 1-12.
BHM(config)#router rip
BHM(config-router)#network 172.18.0.0
BHM(config-router)#network 172.17.0.0
BHM(config-router)#exit
BHM(config)#exit
Task 5: Save the BHM Router Configuration
BHM#copy running-config startup-config
Destination filename [startup-config]?[Enter]
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56 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 6: Configure the Hosts
Configure the hosts with proper IP addresses, subnet masks, and default gateways. Document your choices
here:
Host connected to router GAD
IP address: 172.16.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.16.0.1
Host connected to router BHM
IP address: 172.18.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.18.0.1
Task 7: Verify that the Internetwork Is Functioning
Step 1. From each router, ping the other router’s Fast Ethernet interface.
Step 2. From the host that is attached to GAD, ping the other host that is attached to the BHM router.
Was the ping successful? Yes
Step 3. From the host that is attached to BHM, ping the other host that is attached to the GAD router.
Was the ping successful? Yes
Step 4. If the answer is no for either question, troubleshoot the router configurations to find the error.
Then, do the pings again until the answer to both questions is yes.
Task 8: Enable RIPv2 Routing
Enable version 2 of the RIP routing protocol on both the GAD and BHM routers.
GAD(config)#router rip
GAD(config-router)#version 2
GAD(config-router)#exit
GAD(config)#exit
BHM(config)#router rip
BHM(config-router)#version 2
BHM(config-router)#exit
BHM(config)#exit
Task 9: Ping All Interfaces on the Network from Each Host
Step 1. Could you still ping all of the interfaces on the network from each host? Yes
Step 2. If not, troubleshoot the network and ping again.
Step 3. Upon completion of the previous steps, log off (by typing exit) and turn the router off. Then,
remove and store the cables and adapter.

Curriculum Lab 1-4: Verifying RIPv2 Configuration (1.2.5)
Figure 1-34 Topology for Lab 1-4
Table 1-13 Lab Equipment Configuration
Router Router Name Fast Ethernet 0 Address Interface Type Serial 0 Address
Designation
Router 1 GAD 172.16.0.1 DCE 172.17.1.1
Router 2 BHM 172.18.0.1 DTE 172.17.1.2
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both interfaces on both routers is 255.255.0.0.
Objectives
Straight-Through Cable
■ Configure RIPv1 and RIPv2 on routers.
■ Use show commands to verify RIPv2 operation.
Chapter 1: Introduction to Classless Routing 57
Router 1 Router 2
Rollover (Console) Cable
Crossover Cable
Serial Cable
Background/Preparation
Cable a network that is similar to the one in Figure 1-34. You can use any router that meets the interface
requirements in Figure 1-34 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before continuing with this lab.

58 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 1: Configure the Routers
On the routers, configure the hostnames, console, virtual terminal, and enable passwords. Next, configure
the serial (IP address and clock rate) and Fast Ethernet (IP address) interfaces. Finally, configure IP hostnames.
If you have problems performing the basic configuration, refer to Lab 1-2, “Review of Basic
Router Configuration with RIP.” You can also configure optional interface descriptions and message of the
day banners. Be sure to save the configurations you just created.
Task 2: Configure the Routing Protocol on Router Gadsden
Go to the correct command mode and configure RIP routing on the GAD router according to Table 1-13.
GAD(config)#router rip
GAD(config-router)#network 172.16.0.0
GAD(config-router)#network 172.17.0.0
GAD(config-router)#exit
GAD(config)#exit
Task 3: Save the Gadsden Router Configuration
Any time that changes are correctly made to the running configuration, you should save them to the startup
configuration. Otherwise, if you reload or power cycle the router, you will lose the changes that are not in
the startup configuration.
Task 4: Configure the Routing Protocol on Router BHM
Go to the correct command mode and configure RIP routing on the BHM router according to Table 1-13.
BHM(config)#router rip
BHM(config-router)#network 172.18.0.0
BHM(config-router)#network 172.17.0.0
BHM(config-router)#exit
BHM(config)#exit
Task 5: Save the BHM Router Configuration
Enter the command copy run start to save the current running configuration to NVRAM.
Task 6: Configure the Hosts
Configure the hosts with proper IP addresses, subnet masks, and default gateways. Document your choices
here:
Host connected to router GAD
IP address: 172.16.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.16.0.1
Host connected to router BHM
IP address: 172.18.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.18.0.1

Task 7: Verify that the Internetwork Is Functioning
Step 1. From each router, ping the other router’s Fast Ethernet interface.
Step 2. From the host that is attached to GAD, ping the other host that is attached to the BHM router.
Was the ping successful? Yes
Step 3. From the host that is attached to BHM, ping the other host that is attached to the GAD router.
Was the ping successful? Yes
Step 4. If the answer is no for either question, troubleshoot the router configurations to find the error.
Then, do the pings again until the answer to both questions is yes.
Task 8: Show the Routing Tables for Each Router
From enable (privileged EXEC) mode, examine the routing table entries by using the show ip route command
on each router.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.16.0.0/16 is directly connected, FastEthernet0
R 172.18.0.0/16 [120/1] via 172.17.1.2, Serial0
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.18.0.0/16 is directly connected, FastEthernet0
R 172.16.0.0/16 [120/1] via 172.17.1.1, 00:00:27, Serial0
What are the entries in the GAD routing table?
C 172.17.0.0/16 is directly connected, Serial0
C 172.16.0.0/16 is directly connected, FastEthernet0
R 172.18.0.0/16 [120/1] via 172.17.1.2, Serial0
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60 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
What are the entries in the BHM routing table?
C 172.17.0.0/16 is directly connected, Serial0
C 172.18.0.0/16 is directly connected, FastEthernet0
R 172.16.0.0/16 [120/1] via 172.17.1.1, 00:00:27, Serial0
Task 9: Enable RIPv2 Routing
Enable Version 2 of the RIP routing protocol on the GAD and BHM routers.
GAD(config)#router rip
GAD(config-router)#version 2
GAD(config-router)#exit
GAD(config)#exit
BHM(config)#router rip
BHM(config-router)#version 2
BHM(config-router)#exit
BHM(config)#exit
Task 10: Show the Routing Tables
Show the routing tables on both routers again.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.16.0.0/16 is directly connected, FastEthernet0
R 172.18.0.0/16 [120/1] via 172.17.1.2, Serial0
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.18.0.0/16 is directly connected, FastEthernet0
R 172.16.0.0/16 [120/1] via 172.17.1.1, 00:00:45, Serial0

Have they changed now that RIPv2 is being used instead of RIPv1? No
What is the difference between RIPv2 and RIPv1?
RIPv2 supports VLSM and RIPv1 does not.
What must you do to see a difference between RIPv2 and RIPv1?
Change the subnet mask of the interfaces.
Task 11: Change the Fast Ethernet IP Subnet Mask on Router GAD
Change the subnet mask on router GAD from a Class B (255.255.0.0) to a Class C (255.255.255.0). Use
the same IP address.
GAD(config)#interface fastethernet 0
GAD(config-if)#ip address 172.16.0.1 255.255.255.0
GAD(config-if)#exit
How does this change affect the address for the Fast Ethernet interface?
The IP address of the interface remains the same, but it belongs to a smaller subnet.
Task 12: Show the GAD Routing Table
Show the GAD routing table.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.0.0 is directly connected, FastEthernet0
R 172.18.0.0/16 [120/1] via 172.17.1.2, Serial0
Has the output changed now that you have added a subnetted IP address? Yes
How has it changed?
There is a new route to the subnet 172.16.0.0/24.
Task 13: Show the BHM Routing Table
Show the BHM routing table.
BHM#show ip route
Chapter 1: Introduction to Classless Routing 61
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP

62 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
R 172.16.0.0/16 [120/1] via 172.17.1.1, 00:00:24, Serial0
172.18.0.0/24 is subnetted, 1 subnets
C 172.18.0.0 is directly connected, FastEthernet0
Has the output changed now that you have added a subnetted IP address? Yes
Task 14: Change the Network Addressing Scheme
Change the addressing scheme of the network to a single Class B network with a Class C subnet (8 bits of
subnetting).
On the BHM router:
BHM(config)#interface serial 0
BHM(config-if)#ip address 172.16.1.2 255.255.255.0
BHM(config-if)#exit
BHM(config)#interface fastethernet 0
BHM(config-if)#ip address 172.16.3.1 255.255.255.0
BHM(config-if)#exit
BHM(config)#exit
BHM(config)#router rip
BHM(config-router)#no network 172.18.0.0
BHM(config-router)#no network 172.17.0.0
BHM(config-router)#network 172.16.1.0
BHM(config-router)#network 172.16.3.0
BHM(config-router)#exit
On the GAD router:
GAD(config)#interface serial 0
GAD(config-if)#ip address 172.16.1.1 255.255.255.0
GAD(config-if)#exit
GAD(config)#router rip
GAD(config-router)#no network 172.17.0.0
GAD(config-router)#network 172.16.1.0
GAD(config-router)#exit
Task 15: Show the Routing Table for Router GAD
Show the GAD routing table.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP

i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, FastEthernet0
C 172.16.1.0 is directly connected, Serial0
R 172.16.3.0 [120/1] via 172.16.1.2, Serial0
Has the output changed now that you have added a subnetted IP address? Yes
How has it changed?
There are three subnets, two of which are directly connected, and the other subnet, 172.16.3.0, is learned
through RIP via interface serial 0.
Task 16: Show the Routing Table for Router BHM
Show the BHM routing table.
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
R 172.16.0.0 [120/1] via 172.16.1.1, 00:00:05, Serial0
C 172.16.1.0 is directly connected, Serial0
C 172.16.3.0 is directly connected, FastEthernet0
Has the output changed now that you have added a subnetted IP address? Yes
Task 17: Change the Host Configurations
Change the host configuration to reflect the new IP addressing scheme of the network.
Host connected to router GAD
IP address: 172.16.0.2
Subnet mask: 255.255.255.0
Default gateway: 172.16.0.1
Host connected to router BHM
IP address: 172.16.3.2
Subnet mask: 255.255.255.0
Default gateway: 172.16.3.1
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64 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 18: Ping All Interfaces on the Network from Each Host
Step 1. Could you still ping all of the interfaces on the network from each host? Yes
Step 2. If not, troubleshoot the network and ping again.
Task 19: Use show ip route to See Different Routes by Type
Step 1. Enter show ip route connected on the GAD router.
What networks are displayed?
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, FastEthernet0
C 172.16.1.0 is directly connected, Serial0
What interface is directly connected?
C 172.16.0.0 is directly connected, Ethernet0
C 172.16.1.0 is directly connected, Serial0
Step 2. Enter show ip route rip.
172.16.0.0/24 is subnetted, 3 subnets
R 172.16.3.0 [120/1] via 172.16.1.2, Serial0
Step 3. List the routes in the routing table.
R 172.16.3.0 [120/1] via 172.16.1.2, Serial0
What is the administrative distance? 120
Step 4. Enter show ip route connected on the BHM router.
What networks are displayed?
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.1.0 is directly connected, Serial0
C 172.16.3.0 is directly connected, Ethernet0
What interface is directly connected?
C 172.16.1.0 is directly connected, Serial0
C 172.16.3.0 is directly connected, Ethernet0
Step 5. Enter show ip route rip.
Step 6. List the routes in the routing table
172.16.0.0/24 is subnetted, 3 subnets
R 172.16.0.0 [120/1] via 172.16.1.1, 00:00:15, Serial0
Task 20: Use the show ip protocol Command
Enter the show ip protocol command on the GAD router.
Routing Protocol is “rip”
Sending updates every 30 seconds, next due in 1 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is
Incoming update filter list for all interfaces is

Redistributing: rip
Default version control: send version 2, receive version 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0 2 2
Serial0 2 2
Routing for Networks:
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
172.17.1.2 120 00:13:21
172.16.1.2 120 00:00:24
172.17.0.2 120 00:35:08
Distance: (default is 120)
When will the routes be flushed? 240 seconds
What is the default distance listed for RIP? 120
Task 21: Remove the Version 2 Option for RIP
Remove the version 2 option on the RIP configuration for both routers.
GAD(config)#router rip
GAD(config-router)#no version 2
GAD(config-router)#exit
BHM(config)#router rip
BHM(config-router)#no version 2
BHM(config-router)#exit
Task 22: Show the Routing Table for Router GAD
Show the GAD routing table.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR, P - periodic downloaded static route
T - traffic engineered route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
C 172.16.0.0 is directly connected, FastEthernet0
C 172.16.1.0 is directly connected, Serial0
R 172.16.3.0 [120/1] via 172.16.1.2, Serial0
Has the output changed now that RIPv2 has been removed? No
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66 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 23: Show the Routing Table for Router BHM
Step 1. Show the BHM routing table.
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B – BGP
area
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 3 subnets
R 172.16.0.0 [120/1] via 172.16.1.1, 00:00:01, Serial0
C 172.16.1.0 is directly connected, Serial0
C 172.16.3.0 is directly connected, Ethernet0
Has the output changed now that RIPv2 has been removed? No
Step 2. Upon completion of the previous step, log off (by typing exit) and turn the router off. Then,
remove and store the cables and adapter.
Curriculum Lab 1-5: Troubleshooting RIPv2 Using debug
(1.2.6)
Figure 1-35 Topology for Lab 1-5
Straight-Through Cable
Table 1-14 Lab Equipment Configuration
Router Designation Router Name Fast Ethernet 0 Address Interface Type
Serial 0 Address
Router 1 GAD 172.16.0.1 DCE 172.17.1.1
Router 2 BHM 172.18.0.1 DTE 172.17.1.2
The enable secret password for both routers is class.
Router 1 Router 2
Rollover (Console) Cable
Crossover Cable
Serial Cable

The enable, VTY, and console password for both routers is cisco.
The subnet mask for both interfaces on both routers is 255.255.0.0.
Objectives
■ Configure RIP Version 2 on both routers.
■ Use debug commands to verify proper RIP operation and analyze data that is transmitted between
routers.
Background/Preparation
Cable a network that is similar to the one in Figure 1-35. You can use any router that meets the interface
requirements in Figure 1-35 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, configure the hostnames, console, virtual terminal, and enable passwords. Next, configure
the serial (IP address and clock rate) and Fast Ethernet (IP address) interfaces. Finally, configure IP hostnames.
If you have problems performing the basic configuration, refer to Lab 1-2, “Review of Basic
Router Configuration with RIP.” You can also configure optional interface descriptions and message of the
day banners. Be sure to save the configurations you just created.
Task 2: Configure the Routing Protocol on Router GAD
Go to the proper command mode and configure RIP routing on the GAD router according to Table 1-14.
Task 3: Save the GAD Router Configuration
Chapter 1: Introduction to Classless Routing 67
Anytime that changes are correctly made to the running configuration, you should save them to the startup
configuration. Otherwise, if you reload or power cycle the router, you will lose the changes that are not in
the startup configuration.
Task 4: Configure the Routing Protocol on Router BHM
Go to the proper command mode and configure RIP routing on the BHM router according to Table 1-14.

68 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 5: Save the BHM Router Configuration
Enter the command copy run start to save the current running configuration to NVRAM.
Task 6: Configure the Hosts
Configure the hosts with proper IP addresses, subnet masks, and default gateways. Document your choices
here:
Host connected to router GAD
IP address: 172.16.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.16.0.1
Host connected to router BHM
IP address: 172.18.0.2
Subnet mask: 255.255.0.0
Default gateway: 172.18.0.1
Task 7: Verify the Internetwork Is Functioning
Step 1. From each router, ping the other router’s Fast Ethernet interface.
Step 2. From the host that is attached to GAD, ping the other host that is attached to the BHM router.
Was the ping successful? Yes
Step 3. From the host that is attached to BHM, ping the other host that is attached to the GAD router.
Was the ping successful? Yes
Step 4. If the answer is no for either question, troubleshoot the router configurations to find the error.
Then, do the pings again until the answer to both questions is yes.
Task 8: Show the debug ip Command Options
At the privileged EXEC mode prompt, type debug ip ?.
cache IP cache operations
dhcp Dynamic Host Configuration Protocol
eigrp IP-EIGRP information
error IP error debugging
ftp FTP dialogue
html HTML connections
http HTTP connections
icmp ICMP transactions
igrp IGRP information
interface IP interface configuration changes
mpacket IP multicast packet debugging
nat NAT events
ospf OSPF information
packet General IP debugging and IPSO security transactions
peer IP peer address activity

policy Policy routing
rip RIP protocol transactions
routing Routing table events
rtp RTP information
security IP security options
socket Socket event
tcp TCP information
tempacl IP temporary ACL
udp UDP based transactions
Which routing protocols have debug commands?
EIGRP, IGRP, OSPF, and RIP have debug commands.
Task 9: Show the debug ip rip Command Options
At the privileged EXEC mode prompt, type debug ip rip ?.
database RIP database events
events RIP protocol events
trigger RIP trigger extension
How many options are available for debug ip rip ? 3
Task 10: Show the RIP Routing Updates
Step 1. From enable (privileged EXEC) mode, examine the routing table entries by using the debug ip
rip command on each router.
What three operations that take place are listed in the RIP debug statements?
Receive routing update, Send an update, and Build update entries are listed.
Step 2. Turn off debugging by typing either no debug ip rip or undebug all.
Task 11: Enable RIPv2 Routing on Router GAD Only
Enable version 2 of the RIP routing protocol on the GAD router only.
GAD(config)#router rip
GAD(config-router)#version 2
Task 12: Restart the Debug Function on Router GAD
Does a problem occur now that RIPv2 is configured on the GAD router? Yes
If so, what is the problem?
It does not accept updates from BHM because of the version difference.
RIP: ignored v1 packet from 172.17.1.2 (illegal version)
Chapter 1: Introduction to Classless Routing 69

70 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 13: Clear the Routing Table
Step 1. Instead of waiting for the routes to time out, type clear ip route *. Then type show ip route.
What has happened to the routing table?
The route to 172.18.0.1 is no longer there.
GAD#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
C 172.16.0.0/16 is directly connected, FastEthernet0/0
Will the routing table be updated to include RIP routes if the debug output says the update is
ignored? No
Step 2. Turn off debugging by typing either no debug ip rip or undebug all.
Task 14: Start the Debug RIP Function
Start the debug RIP function on the BHM router again by typing debug ip rip.
Does a problem occur now that the GAD router is configured with RIPv2? No
If so, what is the problem?
There is no problem on BHM because RIPv1 is accepting the RIPv2 updates from GAD.
RIP: received v2 update from 172.17.1.1 on Serial0
172.16.0.0/16 via 0.0.0.0 in 1 hops
Task 15: Clear the Routing Table
Step 1. Instead of waiting for the routes to time out, type clear ip route *. Then type show ip route.
What has happened to the routing table?
Nothing, all routes are still there.
BHM#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
area
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 172.17.0.0/16 is directly connected, Serial0
R 172.16.0.0/16 [120/1] via 172.17.1.1, 00:00:20, Serial0
C 172.18.0.0/16 is directly connected, FastEthernet0/0

Will the routing table be updated to include RIP routes if the update is from RIPv2? Yes
Step 2. Turn off debugging by typing either no debug ip rip or undebug all.
Task 16: Enable RIPv2 Routing on Router BHM
Enable RIPv2 on the BHM router.
BHM(config)#router rip
BHM(config-router)#version 2
Task 17: Use the Debug Function to See Packet Traffic on a
Router
Use the debug function to see packet traffic on the BHM router by typing debug ip packet at the privileged
EXEC mode prompt.
When a RIP update is sent, how many source addresses are used? 2
Why are multiple source addresses used?
One is used for each network the router will send and receive updates with.
What is the source address that is used?
172.16.0.1 and 172.17.1.1
Why is this address used?
It is the originating interface from which the packet is sent.
Task 18: Start the debug ip rip database Function on Router BHM
Step 1. Start the RIP database debugging by typing debug ip rip database. Then, clear the routing
table by typing clear ip route *.
Are the old routes in the table deleted? Yes
Are new routes added back into the table? Yes
What does the last entry in the debug output say?
RIP-DB: adding 172.16.0.0/16 (metric 1) via 172.17.1.1 on Serial0 to RIP database.
Step 2. Turn off debugging by typing either no debug ip rip or undebug all.
Task 19: Use the Debug Function to See Routing Updates
Step 1. Use the debug function to see routing updates by typing debug ip rip events in privileged
EXEC mode on the BHM router.
What interfaces are the routing updates sent on?
Fast Ethernet 0/0 and serial 0.
How many routes are in the routing updates that are being sent? 2
Chapter 1: Introduction to Classless Routing 71
Step 2. Upon completion of the previous steps, log off (by typing exit) and turn the router off. Then,
remove and store the cables and adapter.

72 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Comprehensive Lab 1-6: Default Routing and RIPv2
Figure 1-36 Default Routing and RIPv2 Topology
192.168.1.128/26
Address Space
192.168.1.0/24
S0/0
DCE
Table 1-15 Addressing Scheme
192.168.1.0/26
S0/0
Fa0/0
RTA
RIPv2
Fa0/0 Fa0/0
RTC
S0/1
192.168.1.248/30 S0/0
DCE
RTB
Device Interface IP Address Subnet Mask
S0/1
DCE
192.168.1.252/30 192.168.1.244/30
ISP S0/0 209.165.201.1 255.255.255.252
Lo0/0 209.165.202.129 255.255.255.252
RTA Fa0/0 192.168.1.1 255.255.255.192
S1/0 209.165.201.2 255.255.255.252
S0/1 192.168.1.245 255.255.255.252
S0/0 192.168.1.254 255.255.255.252
RTB S0/1 192.168.1.246 255.255.255.192
Fa0/0 192.168.1.65 255.255.255.192
S0/0 192.168.1.249 255.255.255.252
RTC S0/1 192.168.1.250 255.255.255.252
S1/0
209.165.201.2/30
209.165.201.1/30
S0/0
DCE
Fa0/0 192.168.1.129 255.255.255.192
S0/0 192.168.1.253 255.255.255.252
S0/1
192.168.1.64/26
ISP
Public Web Server
209.165.202.129/32

Objectives
■ Review basic router configurations.
■ Configure RIPv2.
■ Configure static and default routing.
■ Verify connectivity and troubleshoot problems.
Equipment
The topology shown in Figure 1-36 is using 2600 series routers. This lab can be done with any combination
of 1700, 2500, and 2600 series routers. If a router with three serial interfaces is not available, you can
use a router with two Ethernet interfaces and attach the ISP router through the Ethernet interfaces. If a
router with four interfaces is not available, you can simulate the LAN off of RTA with a loopback instead
of using the Ethernet interface.
NetLab Compatibility Notes
Most of this lab can be completed on a standard NetLab three router pod. To simulate the ISP connection,
simply configure a loopback address. However, you will not be able to test connectivity to the Public Web
Server.
Task 1: Cable the Topology and Basic Configurations
Step 1. Cable the topology as shown in Figure 1-36. If DCE/DTE connections and interfaces are different
from those shown in Figure 1-36 and Table 1-15, relabel the figure to match your connections.
Step 2. Configure the routers with basic router configurations, including:
■ Hostnames and host tables
■ Enable secret password and MOTD banner
■ Line configurations
■ IOS-specific commands (e.g. ip subnet-zero with IOS versions prior to 12)
Router(config)#hostname RTA
RTA(config)#ip subnet-zero
RTA(config)#no ip domain-lookup
RTA(config)#ip host WEB 209.165.202.129
RTA(config)#ip host ISP 209.165.201.1
RTA(config)#ip host RTC 192.168.1.253 192.168.1.254
RTA(config)#ip host RTB 192.168.1.246 192.168.1.249
RTA(config)#banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
RTA(config)#line con 0
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#ine aux 0
RTA(config-line)#exec-timeout 30 0
Chapter 1: Introduction to Classless Routing 73

74 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#line vty 0 4
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#end
RTA#copy run start
Task 2: Configure Interfaces and Enable RIPv2
Step 1. Use Table 1-15 and the topology shown in Figure 1-37 to configure each router with the correct
interface addresses.
RTA(config)#interface FastEthernet0/0
RTA(config-if)#description Link to RTA LAN
RTA(config-if)#ip address 192.168.1.1 255.255.255.192
RTA(config-if)#no shutdown
RTA(config-if)#interface Serial0/0
RTA(config-if)#description Link to RTC
RTA(config-if)#ip address 192.168.1.254 255.255.255.252
RTA(config-if)#no shutdown
RTA(config-if)#interface Serial0/1
RTA(config-if)#description Link to RTB
RTA(config-if)#ip address 192.168.1.245 255.255.255.252
RTA(config-if)#clockrate 64000
RTA(config-if)#no shutdown
RTA(config)#interface Serial1/0
RTA(config-if)#description Link to ISP
RTA(config-if)#ip address 209.165.201.2 255.255.255.252
RTA(config-if)#no shutdown
Step 2. If you are not using a router with four interfaces for RTA, you need to simulate ISP. To simulate
an ISP connection, use the following configuration on RTA:
RTA(config)#interface Loopback0
RTA(config-if)#description Simulated Link to ISP
RTA(config-if)#ip address 209.165.201.2 255.255.255.252
Step 3. Configuring RIPv2 requires adding the version 2 command after entering RIP routing configuration
mode. With RIPv2, auto-summary is enabled by default, so you need to add the no
auto-summary command. All connected networks participating in RIP are defined with the
network command in the form of classful networks. In this case, you only need to add the
192.168.1.0 network. Do not configure the ISP link as part of RIP.
RTA(config)#router rip
RTA(config-router)#version 2
RTA(config-router)#network 192.168.1.0
RTA(config-router)#no auto-summary

Task 3: Verify Connectivity
Step 1. You should now have full connectivity between RTA, RTB, and RTC. Issue the show ip route
command to verify full convergence.
Routing table on RTA:
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial1/0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
R 192.168.1.64/26 [120/1] via 192.168.1.246, 00:00:25, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
R 192.168.1.248/30 [120/1] via 192.168.1.246, 00:00:25, Serial0/1
[120/1] via 192.168.1.253, 00:00:04, Serial0/0
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
R 192.168.1.128/26 [120/1] via 192.168.1.253, 00:00:06, Serial0/0
Step 2. Notice that RTA has four connected routes (including the connected route to ISP) and three
RIP routes. RTB and RTC should both have three connected routes and three RIP routes.
Step 3. Pings sourced from any router to a LAN interface on another router should succeed. Make sure
each router can ping the LAN interfaces of the other two routers. RTA pings to RTB and RTC
LAN interfaces are shown here:
RTA#ping 192.168.1.65
Chapter 1: Introduction to Classless Routing 75
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.65, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
RTA#ping 192.168.1.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/29/32 ms

76 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 4: Add ISP Router
Step 1. If you are not simulating the ISP router, configure ISP with the following script:
Router(config)#hostname ISP
ISP(config)#enable secret class
ISP(config)#no ip domain-lookup
ISP(config)#ip host RTA 209.165.201.1
ISP(config)#interface Loopback0
ISP(config-if)#description Public Web Server
ISP(config-if)#ip address 209.165.202.129 255.255.255.255
ISP(config-if)#interface Serial0
ISP(config-if)#description Link to RTA
ISP(config-if)#ip address 209.165.201.1 255.255.255.252
ISP(config-if)#clockrate 64000
ISP(config-if)#no shutdown
ISP(config-if)#exit
ISP(config)#banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
ISP(config)#line con 0
ISP(config-line)#exec-timeout 30 0
ISP(config-line)#password cisco
ISP(config-line)#logging synchronous
ISP(config-line)#login
ISP(config-line)#line aux 0
ISP(config-line)#exec-timeout 30 0
ISP(config-line)#password cisco
ISP(config-line)#logging synchronous
ISP(config-line)#login
ISP(config-line)#line vty 0 4
ISP(config-line)#exec-timeout 30 0
ISP(config-line)#password cisco
ISP(config-line)#logging synchronous
ISP(config-line)#login
ISP(config-line)#end
ISP#copy run start
Step 2. Verify that ISP can now ping the 209.165.201.2 interface on RTA.
ISP#ping RTA
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.201.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/29/32 ms
RTA will not be able to ping the Public Web Server and ISP will not be able to ping beyond the
209.165.201.2 interface of RTA. Why?
The routing table on ISP shows only two directly connected networks. ISP can ping RTA
directly because ISP has a route to the 209.165.201.0/30 network in its routing table. RTA can
reply for the same reason. But RTA does not have a route to host 209.165.202.129/32, nor does

RTA have a default route. ISP cannot ping any of the addresses inside the 192.168.1.0/24
address space because it does not have a route. RTA needs a default route pointing to ISP, and
ISP needs a static route pointing to the 192.168.1.0/24 address space.
Task 5: Configure Static and Default Routing
Step 1. For ISP to be able to send Echo replies back to hosts belonging to the 192.168.1.0/24 address
space, it must have a route. Use the following command on ISP to configure a static route
pointing to the 192.168.1.0/24 address space:
ISP(config)#ip route 192.168.1.0 255.255.255.0 209.165.201.2
Step 2. Now ISP can route back to any host belonging to 192.168.1.0/24. However, RTA, RTB, and
RTC do not yet have a route for any address space other than 192.168.1.0/24. Because ISP represents
the connection to the rest of the world, you need to configure default routing. A router
without a more specific route in the routing table will send traffic to the default route. Use the
following command on RTA to configure a default route:
RTA(config)#ip route 0.0.0.0 0.0.0.0 209.165.201.1
Step 3. If you are simulating ISP, use the following command to configure a default route:
RTA(config)#ip route 0.0.0.0 0.0.0.0 Loopback0
Step 4. Now RTA should be able to ping the Public Web Server. However, RTB and RTC still cannot
ping outside the 192.168.1.0/24 address space. The reason is that RTA does not advertise the
default route unless specifically configured to do so. Use the following command with RIP to
propagate a default route to RTB and RTC in the RIP updates:
RTA(config)#router rip
RTA(config-router)#default-information originate
Note: With RIP routing, depending on the platform and IOS version, you may need to reload the router that is propagating
the default route before the default route will be sent in routing updates.
Task 6: Verify Connectivity and Capture Scripts
Chapter 1: Introduction to Classless Routing 77
Step 1. Verify that all routers now have a default route and can ping the Public Web Server.
Note: If you are simulating ISP, test by pinging the loopback interface, 209.165.201.2 on RTA.
RTA>show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 209.165.201.1 to network 0.0.0.0
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial1/0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks

78 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
R 192.168.1.64/26 [120/1] via 192.168.1.246, 00:00:15, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
R 192.168.1.248/30 [120/1] via 192.168.1.253, 00:00:15, Serial0/0
[120/1] via 192.168.1.246, 00:00:15, Serial0/1
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
R 192.168.1.128/26 [120/1] via 192.168.1.253, 00:00:16, Serial0/0
S* 0.0.0.0/0 [1/0] via 209.165.201.1
RTA>ping WEB
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/38/56 ms
RTB>show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 192.168.1.245 to network 0.0.0.0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
C 192.168.1.64/26 is directly connected, FastEthernet0/0
R 192.168.1.0/26 [120/1] via 192.168.1.245, 00:00:13, Serial0/1
C 192.168.1.248/30 is directly connected, Serial0/0
R 192.168.1.252/30 [120/1] via 192.168.1.250, 00:00:04, Serial0/0
[120/1] via 192.168.1.245, 00:00:13, Serial0/1
C 192.168.1.244/30 is directly connected, Serial0/1
R 192.168.1.128/26 [120/1] via 192.168.1.250, 00:00:04, Serial0/0
R* 0.0.0.0/0 [120/1] via 192.168.1.245, 00:00:13, Serial0/1
RTB>ping WEB
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/38/56 ms
RTC>show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2

area
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 192.168.1.254 to network 0.0.0.0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
R 192.168.1.64/26 [120/1] via 192.168.1.249, 00:00:24, Serial0/1
R 192.168.1.0/26 [120/1] via 192.168.1.254, 00:00:04, Serial0/0
C 192.168.1.248/30 is directly connected, Serial0/1
C 192.168.1.252/30 is directly connected, Serial0/0
R 192.168.1.244/30 [120/1] via 192.168.1.249, 00:00:24, Serial0/1
[120/1] via 192.168.1.254, 00:00:04, Serial0/0
C 192.168.1.128/26 is directly connected, FastEthernet0/0
R* 0.0.0.0/0 [120/1] via 192.168.1.254, 00:00:04, Serial0/0
RTC>ping WEB
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/38/56 ms
Step 2. Troubleshoot, if necessary, to obtain output similar to the preceding output.
Step 3. When finished, capture your scripts for your records and erase/reload the routers.
The following are the ending scripts for this lab tested on NetLab using the 2600 platform with IOS version
12.1(22a):
RTA with connection to ISP router:
hostname RTA
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTB 192.168.1.246 192.168.1.249
ip host RTC 192.168.1.253 192.168.1.254
ip host ISP 209.165.201.1
ip host WEB 209.165.202.129
!
interface FastEthernet0/0
!
description Link to RTA LAN
ip address 192.168.1.1 255.255.255.192
no shutdown
Chapter 1: Introduction to Classless Routing 79

80 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface Serial0/0
!
description Link to RTC
ip address 192.168.1.254 255.255.255.252
no shutdown
interface Serial0/1
!
description Link to RTB
ip address 192.168.1.245 255.255.255.252
clockrate 64000
no shutdown
interface Serial1/0
!
description Link to ISP
ip address 209.165.201.2 255.255.255.252
no shutdown
router rip
!
version 2
network 192.168.1.0
default-information originate
no auto-summary
ip classless
ip route 0.0.0.0 0.0.0.0 209.165.201.1
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 30 0
password cisco

!
logging synchronous
login
end
RTA with simulated ISP:
hostname RTA
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTB 192.168.1.246 192.168.1.249
ip host RTC 192.168.1.253 192.168.1.254
ip host ISP 209.165.201.2
!
interface Loopback0
!
description Simulated Link to ISP
ip address 209.165.201.2 255.255.255.252
interface FastEthernet0/0
!
description Link to RTA LAN
ip address 192.168.1.1 255.255.255.192
no shutdown
interface Serial0/0
!
description Link to RTC
ip address 192.168.1.254 255.255.255.252
clockrate 64000
no shutdown
interface Serial0/1
!
description Link to RTB
ip address 192.168.1.245 255.255.255.252
clockrate 64000
no shutdown
router rip
!
version 2
network 192.168.1.0
default-information originate
no auto-summary
ip classless
ip route 0.0.0.0 0.0.0.0 Loopback0
!
Chapter 1: Introduction to Classless Routing 81

82 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end
RTB configuration:
hostname RTB
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTA 192.168.1.245 192.168.1.254
ip host RTC 192.168.1.250 192.168.1.253
ip host ISP 209.165.201.1
ip host WEB 209.165.202.129
!——————————————————————
!If using a simulated ISP, use the following
!instead of the above ‘ISP’ and ‘WEB’:
!ip host ISP 209.165.201.2
!——————————————————————
!
interface FastEthernet0/0
description Link to RTB LAN
ip address 192.168.1.65 255.255.255.192

!
no shutdown
interface Serial0/0
!
description Link to RTC
ip address 192.168.1.249 255.255.255.252
clockrate 64000
no shutdown
interface Serial0/1
!
description Link to RTA
ip address 192.168.1.246 255.255.255.252
no shutdown
router rip
!
version 2
network 192.168.1.0
no auto-summary
ip classless
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end
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84 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
RTC configuration:
hostname RTC
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTA 192.168.1.254 192.168.1.245
ip host RTB 192.168.1.249 192.168.1.246
ip host ISP 209.165.201.1
ip host WEB 209.165.202.129
!——————————————————————
!If using a simulated ISP, use the following
!instead of the above ‘ISP’ and ‘WEB’:
!ip host ISP 209.165.201.2
!——————————————————————
!
interface FastEthernet0/0
!
description Link to RTC LAN
ip address 192.168.1.129 255.255.255.192
no shutdown
interface Serial0/0
!
description Link to RTA
ip address 192.168.1.253 255.255.255.252
no shutdown
interface Serial0/1
!
description Link to RTB
ip address 192.168.1.250 255.255.255.252
no shutdown
router rip
!
version 2
network 192.168.1.0
no auto-summary
ip classless
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&

!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end
Challenge Lab 1-7: VLSM Design, RIPv2, and Default
Routing
Figure 1-37 VLSM Design, RIPv2, and Default Routing Topology
10.1.8.0/25
10.1.8.128/25
10.1.9.0/25
10.1.9.128/25
Address Space
10.1.0.0/20
Lo1
Lo2
Lo3
Lo4
RTB
S0/1
Chapter 1: Introduction to Classless Routing 85
Public Web Server
209.165.202.129/30
ISP
S0/1
DCE
209.165.201.1/30
209.165.201.2/30
S0/1
172.16.1.0/30 S0/0
DCE
RTA
Lo1
Lo2
Lo3
Lo4
10.1.0.0/25
10.1.0.128/25
10.1.1.0/25
10.1.1.128/25

86 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 1-16 Addressing Scheme
Device Interface IP Address Subnet Mask
ISP S0/0 209.165.201.1 255.255.255.252
Lo0/0 209.165.202.129 255.255.255.252
RTA S0/1 209.165.201.2 255.255.255.252
S0/0 172.16.1.1 255.255.255.252
Lo1 10.1.0.1 255.255.255.128
Lo2 10.1.0.129 255.255.255.128
Lo3 10.1.1.1 255.255.255.128
Lo4 10.1.1.129 255.255.255.128
RTB S0/1 172.16.1.2 255.255.255.252
Objectives
■ Design a scalable addressing scheme.
Lo1 10.1.8.1 255.255.255.128
Lo2 10.1.8.129 255.255.255.128
Lo3 10.1.9.1 255.255.255.128
Lo4 10.1.9.129 255.255.255.128
■ Configure routers with basic configurations using your addressing scheme.
■ Configure dynamic, static, and default routing.
■ Verify connectivity and troubleshoot problems.
Equipment
The topology shown in Figure 1-37 uses 2600 series routers. This lab can be done with any combination of
1700, 2500, and 2600 series routers.
NetLab Compatibility Notes
This lab can be completed on a standard NetLab three router pod.
Task 1: Design the Addressing Scheme
You are given the address space, 10.1.0.0/20. The loopback interfaces on RTA and RTB are used to simulate
different areas of the network. Although each loopback interface could be one LAN or a group of
LANs summarized in one routing update, this discussion simply refers to each loopback interface as a simulated
LAN.
Design an addressing scheme by following these requirements:
Step 1. RTA and RTB will share the 10.1.0.0/20 address space equally. Split the address space into two
equal subnets. Record your subnets with prefix notation in the space provided.
10.1.8.0/21 10.1.0.0/21
Address space for RTB Address space for RTA

Step 2. Each simulated LAN requires a minimum of 100 host addresses. Subnet the address space for
both RTA and RTB, maximizing the total number of subnets while still providing enough host
addresses for each simulated LAN. You will use the first four subnets in each address space.
Record your subnets with prefix notation in the space provided.
Subnets for RTA LANs Subnets for RTB LANs
Lo1 10.1.8.0/25 Lo1 10.1.0.0/25
Lo2 10.1.8.128/25 Lo1 10.1.0.128/25
Lo3 10.1.9.0/25 Lo1 10.1.1.0/25
Lo4 10.1.9.128/25 Lo1 10.1.1.128/25
Step 3. Now label the topology with your subnets and finish filling in the addressing table. Make sure
you record the subnet masks in dotted-decimal format.
Step 4. If required, obtain your instructor’s approval before proceeding.
Instructor Initials _______________
Task 2: Cable the Topology and Basic Configurations
Step 1. Cable the topology as shown in Figure 1-37.
Step 2. Configure the routers with basic router configurations, including
■ Hostnames and host tables
■ Enable secret password and MOTD banner
■ Line configurations
■ IOS-specific commands (that is, ip subnet-zero with IOS versions prior to 12)
See the scripts at the end of this lab for recommended configurations.
Task 3: Configure the Interfaces and Enable RIPv2
Step 1. Configure all interfaces, including the loopbacks, according to your addressing scheme.
Step 2. Configure RIPv2 on RTA and RTB. Make sure to add the 172.16.0.0 network to RIP configuration
on both RTA and RTB. Do not configure RIP on ISP. Do not add the 209.165.201.0/30
network to the RIP configuration on RTA.
See the scripts at the end of the lab for recommended configurations.
Task 4: Configure Static and Default Routing
Step 1. ISP needs two static routes: one pointing to the 10.1.0.0/20 address space and one pointing to
the 172.16.1.0/30 address space. Configure ISP with these static routes.
ISP(config)#ip route 10.1.0.0 255.255.240.0 209.165.201.2
ISP(config)#ip route 172.16.1.0 255.255.255.252 209.165.201.2
Step 2. RTA needs a default route point to ISP. Configure RTA with a default route.
RTA(config)#ip route 0.0.0.0 0.0.0.0 209.165.201.1
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88 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 3. RTA needs to send RTB the default router. Configure RTA to originate default information
within the RIP routing process. Refer to Lab 1-6, if you need help.
RTA(config-router)#default-information originate
Note: With RIP routing, you must reload the router that is propagating the default route before the default route will
be sent in routing updates.
Task 5: Verify Connectivity
Step 1. Verify that all routers now have a default route and can ping the Public Web Server. The routing
tables should have all the routes shown in the following output:
Routing Table for ISP:
Gateway of last resort is not set
172.16.0.0/30 is subnetted, 1 subnets
S 172.16.1.0 [1/0] via 209.165.201.2
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0/1
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
10.0.0.0/20 is subnetted, 1 subnets
S 10.1.0.0 [1/0] via 209.165.201.2
Routing Table for RTA:
Gateway of last resort is 209.165.201.1 to network 0.0.0.0
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/0
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0/1
10.0.0.0/25 is subnetted, 8 subnets
R 10.1.9.0 [120/1] via 172.16.1.2, 00:00:26, Serial0/0
R 10.1.8.0 [120/1] via 172.16.1.2, 00:00:26, Serial0/0
C 10.1.1.0 is directly connected, Loopback3
C 10.1.0.0 is directly connected, Loopback1
R 10.1.9.128 [120/1] via 172.16.1.2, 00:00:27, Serial0/0
R 10.1.8.128 [120/1] via 172.16.1.2, 00:00:27, Serial0/0
C 10.1.1.128 is directly connected, Loopback4
C 10.1.0.128 is directly connected, Loopback2
S* 0.0.0.0/0 [1/0] via 209.165.201.1
Routing Table for RTB:
Gateway of last resort is 172.16.1.1 to network 0.0.0.0
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/1
10.0.0.0/25 is subnetted, 8 subnets
C 10.1.9.0 is directly connected, Loopback3
C 10.1.8.0 is directly connected, Loopback1
R 10.1.1.0 [120/1] via 172.16.1.1, 00:00:20, Serial0/1
R 10.1.0.0 [120/1] via 172.16.1.1, 00:00:20, Serial0/1
C 10.1.9.128 is directly connected, Loopback4

C 10.1.8.128 is directly connected, Loopback2
R 10.1.1.128 [120/1] via 172.16.1.1, 00:00:21, Serial0/1
R 10.1.0.128 [120/1] via 172.16.1.1, 00:00:21, Serial0/1
R* 0.0.0.0/0 [120/1] via 172.16.1.1, 00:00:21, Serial0/1
Step 2. Troubleshoot, if necessary, to obtain output similar to the preceding output.
Step 3. Once finished, capture your scripts for your records and erase/reload the routers.
Task 6: Challenge
Looking forward to your studies of EIGRP, you will learn that it is possible to reduce the size of the routing
tables on RTA and RTB by configuring EIGRP to summarize the simulated LANs into one route.
What summary route would you configure on RTB to send to RTA? Record the summary route with the
correct prefix length here:
10.1.8.0/21
What summary route would you configure on RTA to send to RTB? Record the summary route with the
correct prefix length here:
10.1.0.0/21
What interface would send the summary on RTB?
Serial 0/1
What interface would send the summary on RTA?
Serial 0/0
Now use the Cisco IOS help facility to discover a command you can use to configure a summary route. To
get you started on RTA, enter interface configuration mode for the interface attached to RTB. Then enter
ip ?. Can you find an ip command that looks like a summary route? Continue to use the help facility to
discover all the parameters and configure your summary route.
You may want to help the students through this process of discovering additional features of the IOS by
using the help facility. The following output shows how this discovery process might occur:
RTA(config)#interface s0/0
RTA(config-if)#ip ?
Interface IP configuration subcommands:
access-group Specify access control for packets
accounting Enable IP accounting on this interface
address Set the IP address of an interface
audit Apply IDS audit name
auth-proxy Apply authenticaton proxy
authentication authentication subcommands
bandwidth-percent Set EIGRP bandwidth limit
bgp BGP interface commands
broadcast-address Set the broadcast address of an interface
cef Cisco Express Fowarding interface commands
cgmp Enable/disable CGMP
directed-broadcast Enable forwarding of directed broadcasts
dvmrp DVMRP interface commands
hello-interval Configures IP-EIGRP hello interval
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90 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
helper-address Specify a destination address for UDP broadcasts
hold-time Configures IP-EIGRP hold time
igmp IGMP interface commands
inspect Apply inspect name
irdp ICMP Router Discovery Protocol
load-sharing Style of load sharing
mask-reply Enable sending ICMP Mask Reply messages
mobile Mobile IP support
mrm Configure IP Multicast Routing Monitor tester
mroute-cache Enable switching cache for incoming multicast packets
mtu Set IP Maximum Transmission Unit
multicast IP multicast interface commands
nat NAT interface commands
nhrp NHRP interface subcommands
ospf OSPF interface commands
pgm PGM Reliable Transport Protocol
pim PIM interface commands
policy Enable policy routing
probe Enable HP Probe support
proxy-arp Enable proxy ARP
rarp-server Enable RARP server for static arp entries
redirects Enable sending ICMP Redirect messages
rip Router Information Protocol
route-cache Enable fast-switching cache for outgoing packets
router IP router interface commands
rsvp RSVP interface commands
rtp RTP parameters
sap Session Advertisement Protocol interface commands
sdr Session Directory Protocol interface commands
security DDN IP Security Option
split-horizon Perform split horizon
summary-address Perform address summarization
tcp TCP header compression parameters
unnumbered Enable IP processing without an explicit address
unreachables Enable sending ICMP Unreachable messages
verify Enable per packet validation
vrf VPN Routing/Forwarding parameters on the interface
wccp WCCP interface commands
RTA(config-if)#ip summary-address ?
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
rip Routing Information Protocol (RIP)
RTA(config-if)#ip summary-address rip ?
A.B.C.D IP address

RTA(config-if)#ip summary-address rip 10.1.0.0 ?
A.B.C.D IP network mask
RTA(config-if)#ip summary-address rip 10.1.0.0 255.255.248.0 ?
RTA(config-if)#ip summary-address rip 10.1.0.0 255.255.248.0
RTA(config-if)#end
Notice the subnet mask matches the summary of all the simulated LANs for RTA. This summary should
conform to the subnet the student determined in Task 1, Step 1 above.
Next, encourage the students to use other commands besides show run and show ip route to see the effect
of this configuration. A powerful command that displays routing configuration information is show ip protocols.
Notice the highlighted portion of the output shows the summary route.
RTA#show ip protocols
Routing Protocol is “rip”
Sending updates every 30 seconds, next due in 23 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive version 2
Interface Send Recv Triggered RIP Key-chain
Serial0/0 2 2
Loopback1 2 2
Loopback2 2 2
Loopback3 2 2
Loopback4 2 2
Automatic network summarization is not in effect
Address Summarization:
10.1.0.0/21 for Serial0/0
Maximum path: 4
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
172.16.1.2 120 00:00:10
Distance: (default is 120)
Chapter 1: Introduction to Classless Routing 91
Now verify that RTB has received the new summary route as highlighted in the following output. All the
routes may be listed, including the /25 routes, because RIP has not yet timed out these routes. You can
either wait for the /25 routes to be flushed or simply refresh the routing table by using the clear ip route *
command.
RTB#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

92 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 172.16.1.1 to network 0.0.0.0
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/1
10.0.0.0/8 is variably subnetted, 9 subnets, 2 masks
C 10.1.9.0/25 is directly connected, Loopback3
C 10.1.8.0/25 is directly connected, Loopback1
R 10.1.1.0/25 [120/1] via 172.16.1.1, 00:00:55, Serial0/1
R 10.1.0.0/21 [120/1] via 172.16.1.1, 00:00:28, Serial0/1
R 10.1.0.0/25 [120/1] via 172.16.1.1, 00:00:55, Serial0/1
C 10.1.9.128/25 is directly connected, Loopback4
C 10.1.8.128/25 is directly connected, Loopback2
R 10.1.1.128/25 [120/1] via 172.16.1.1, 00:00:55, Serial0/1
R 10.1.0.128/25 [120/1] via 172.16.1.1, 00:00:55, Serial0/1
R* 0.0.0.0/0 [120/1] via 172.16.1.1, 00:00:28, Serial0/1
RTB#clear ip route *
RTB#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 172.16.1.1 to network 0.0.0.0
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/1
10.0.0.0/8 is variably subnetted, 5 subnets, 2 masks
C 10.1.9.0/25 is directly connected, Loopback3
C 10.1.8.0/25 is directly connected, Loopback1
R 10.1.0.0/21 [120/1] via 172.16.1.1, 00:00:03, Serial0/1
C 10.1.9.128/25 is directly connected, Loopback4
C 10.1.8.128/25 is directly connected, Loopback2
R* 0.0.0.0/0 [120/1] via 172.16.1.1, 00:00:03, Serial0/1

Now configure RTB to summarize the simulated LANs in RIP routing updates sent to RTA. What is the
command, including router prompt?
RTB(config-if)#ip summary-address rip 10.1.8.0 255.255.248.0
Clear the routing table on RTA and verify that RTA lists only the summary route for RTB. Test the route
by pinging the loopback interfaces on RTB.
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 209.165.201.1 to network 0.0.0.0
172.16.0.0/30 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Serial0/0
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0/1
10.0.0.0/8 is variably subnetted, 5 subnets, 2 masks
R 10.1.8.0/21 [120/1] via 172.16.1.2, 00:00:05, Serial0/0
C 10.1.1.0/25 is directly connected, Loopback3
C 10.1.0.0/25 is directly connected, Loopback1
C 10.1.1.128/25 is directly connected, Loopback4
C 10.1.0.128/25 is directly connected, Loopback2
S* 0.0.0.0/0 [1/0] via 209.165.201.1
RTA#ping 10.1.8.1
Chapter 1: Introduction to Classless Routing 93
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.8.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 ms
RTA#ping 10.1.8.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.8.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
RTA#ping 10.1.9.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.9.129, timeout is 2 seconds:
!!!!!

94 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 ms
RTA#ping 10.1.9.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.9.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/29/32 ms
The following are the ending scripts for this lab tested on NetLab using the 2600 platform with
IOS version 12.1(22a).
ISP configuration:
hostname ISP
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTA 209.165.201.2
!
interface Loopback0
!
description Public Web Server
ip address 209.165.202.129 255.255.255.255
interface Serial0/1
!
description Link to RTA
ip address 209.165.201.1 255.255.255.252
clockrate 64000
no shutdown
ip classless
ip route 10.1.0.0 255.255.240.0 209.165.201.2
ip route 172.16.1.0 255.255.255.252 209.165.201.2
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0

password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end
RTA configuration:
hostname RTA
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTB 172.16.1.2
ip host ISP 209.165.201.1
ip host WEB 209.165.202.129
!
interface Loopback1
!
description RTA Simulated LAN1
ip address 10.1.0.1 255.255.255.128
interface Loopback2
!
description RTA Simulated LAN2
ip address 10.1.0.129 255.255.255.128
interface Loopback3
!
description RTA Simulated LAN3
ip address 10.1.1.1 255.255.255.128
interface Loopback4
!
description RTA Simulated LAN4
ip address 10.1.1.129 255.255.255.128
interface Serial0/0
!
description Link to RTB
ip address 172.16.1.1 255.255.255.252
ip summary-address rip 10.1.0.0 255.255.248.0
clockrate 64000
no shutdown
interface Serial0/1
Chapter 1: Introduction to Classless Routing 95

96 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
description Link to ISP
ip address 209.165.201.2 255.255.255.252
no shutdown
router rip
!
version 2
network 10.0.0.0
network 172.16.0.0
default-information originate
no auto-summary
ip classless
ip route 0.0.0.0 0.0.0.0 209.165.201.1
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end
RTB configuration:
hostname RTB
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host WEB 209.165.202.129

ip host ISP 209.165.201.1
ip host RTA 172.16.1.1
!
interface Loopback1
!
description Simulated RTB LAN1
ip address 10.1.8.1 255.255.255.128
interface Loopback2
!
description Simulated RTB LAN2
ip address 10.1.8.129 255.255.255.128
interface Loopback3
!
description Simulated RTB LAN3
ip address 10.1.9.1 255.255.255.128
interface Loopback4
!
description Simulated RTB LAN4
ip address 10.1.9.129 255.255.255.128
interface Serial0/1
!
description Link to RTA
ip address 172.16.1.2 255.255.255.252
ip summary-address rip 10.8.0.0 255.255.248.0
no shutdown
router rip
!
version 2
network 10.0.0.0
network 172.16.0.0
no auto-summary
ip classless
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 30 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 30 0
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98 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 30 0
password cisco
logging synchronous
login
end

CHAPTER 2
Single-Area OSPF
The Study Guide portion of this chapter uses a combination of matching, fill in the blank, open-ended
questions, and unique custom exercises to test your knowledge on the theory of link-state routing protocols,
single-area OSPF concepts, and single-area OSPF configuration.
The Lab Exercises portion of this chapter includes all the online curriculum labs as well as a comprehensive
lab and a challenge lab to ensure that you have mastered the practical, hands-on skills needed about
single-area OSPF.

100 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
Link-State Routing Overview
In this section of the Study Guide, you complete exercises that solidify your knowledge of the features,
benefits, and limitations of link-state routing protocols. You also work on your OSPF vocabulary. The following
exercises build on each other and are best done in sequence.
Vocabulary Exercise: Matching
Match the definition on the left with a term on the right. This exercise is not necessarily a one-to-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
Finally, some terms may not be used at all.
Definition
a. A collection of networks under a common
administration that share a common routing
strategy
b. Link-state routing protocol
c. Attaches to multiple areas, maintains separate
link-state databases for each area it is connected
to, and routes traffic destined for or
arriving from other areas
d. Describes the details of OSPF link-state concepts
and operations
e. A listing of links used by the SPF algorithm
to calculate the best paths through the network
and build the SPF tree
f. A group of contiguous subnets that is a logical
subdivision of an autonomous system
g. Flooded throughout an area when a failure
occurs in the network, such as when a neighbor
becomes unreachable
h. An open-standard, link-state routing protocol
designed to address the limitations of RIP
i. Calculates and maintains a complex database
of topology information
j. Within each autonomous system, a contiguous
transition area through which all other
areas communicate
k. Connects to an external routing domain that
uses a different routing policy
l. The part of the network through which multiple
OSPF areas connect
m. When this is not equal, the router with the highest
will be the DR regardless of router ID values
n. The Router ID for an OSPF router if no loopbacks
are configured
Term
e link-state database
b Intermediate System-to-Intermediate
System (IS-IS)
f area
g link-state advertisements
n highest IP address
b, h Open Shortest Path First (OSPF)
m router priority
l area 0
d RFC 2328
i Shortest Path First algorithm
a autonomous system
c Area Border Router (ABR)
e topological database
l, j the backbone
k Autonomous System Boundary Router
(ASBR)
(not used) lowest IP address
i Dijkstra

Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
Open Shortest Path First (OSPF) and Intermediate System-to-Intermediate System (IS-IS) protocols are
classified as link-state routing protocols. RFC 2328 describes OSPF link-state concepts and operations.
Link-state routing protocols were designed to overcome the limitations of distance vector routing protocols.
When a failure occurs in the network, such as when a neighbor becomes unreachable, link-state protocols
flood LSAs (acronym) using a special multicast address throughout an area. A link is the same as an interface
on a router. The state of the link is a description of an interface and the relationship to its neighboring
routers. The collection of link states forms a link-state database, sometimes called a topological database.
Link-state routers find the best paths to destinations by applying the Dijkstra or Shortest Path First algorithm
against the link-state database to build the shortest-path first (SPF) tree, with the local router as the
root. The best paths are then selected from the SPF tree and placed in the forwarding database.
An autonomous system (AS) consists of a collection of networks under a common administration that
share a common routing strategy. The backbone area is the transition point between areas in an AS because
all other areas communicate through it.
Compare and Contrast Exercise
In the following table, list the benefits and limitations of link-state routing protocols. You should have at
least four entries for each side of the table.
Benefits Limitations
Chapter 2: Single-Area OSPF 101
Link-state protocols use cost metrics to choose Link-state protocols require a topology database, an
paths through the network. The cost metric adjacency database, and a forwarding database.
reflects the capacity of the links on those paths. Using all these databases can require a significant
amount of memory in large or complex networks.
Routing updates are more infrequent.
Dijkstra’s algorithm requires CPU cycles to calculate
The network can be segmented into area the best paths through the network. If the network is
hierarchies, limiting the scope of route changes. large or complex, link-state protocols can use a
significant amount of CPU time.
Link-state protocols send only updates of a
topology change. By using triggered, flooded In a multiarea design, an area router must always
updates, link-state protocols can immediately have a path to the backbone or else the router will
report changes in the network topology to all have no connectivity to the rest of the network.
routers in the network. This immediate reporting Additionally, the backbone area must remain
generally leads to fast convergence times. contiguous at all times to avoid some areas becoming
isolated (partitioned).
Because each router has a complete and
synchronized picture of the network, it is very Configuring a link-state protocol in a large network
difficult for routing loops to occur. can be challenging.
Because LSAs are sequenced and aged, routers Interpreting the information that is stored in the
always base their routing decisions on the most topology, neighbor databases, and routing table
recent set of information. requires a good understanding of the concepts of
link-state routing.
With careful network design, the link-state
database sizes can be minimized, leading to During the initial discovery process, link-state routing
smaller Dijkstra calculations and faster protocols can flood the network with LSAs and thereconvergence.
by significantly decrease the network’s capability to
transport data.
Link-state protocols usually scale to larger
networks than distance vector protocols do,
particularly the traditional distance vector
protocols such as RIPv1 and IGRP.

102 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Concept Questions
What two names refer to the same algorithm used by all link-state routing protocols?
Link-state routing protocols were made possible by the algorithm formulated by Edsger Wybe Dijkstra.
Thus, it is called the Dijkstra algorithm. More generically, it is called the Shortest Path First algorithm. For
more on Dijkstra, visit Wikipedia at http://en.wikipedia.org/wiki/Edsger Dijkstra.
What is the difference between the way link-state routing protocols view the network and the way distance
vector routing protocols view the network?
Link-state routing protocols build a tree-like structure of the network, with the local router as the root of
the tree. Each link-state router has knowledge of the entire network. Link-state routers do not depend on
other routers to advertise the best route. Link-state routers calculate an algorithm to determine the best
route to the destination. Distance vector routing has also been called “routing by rumor” and “gossip routing.”
Distance vector routers depend upon directly connected neighbors to advertise the best route to the
destination.
Journal Entry
Describe a network implementation where a distance vector routing protocol would be preferred over a
link-state routing protocol.
First, the current networking devices may not support link-state routing, and the budget for the implementation
may not be sufficient to purchase additional equipment.
Second, the network may be simple enough that the benefits of a link-state routing protocol is overkill. For
example, a network with only a handful of subnets, a few routers and servers, and only one gateway would
not normally need the features of a link-state routing protocol. In fact, you may not want to run a routing
protocol at all. Instead, you may want to use static routes.
Finally, the network administration of the network may not have the necessary training and skills to implement
and monitor a link-state routing protocol, which can be more complex than distance vector routing or
static routing.
Single-Area OSPF Concepts
One of the main limitations of OSPF is its sheer complexity. Although you are only responsible for understanding
single-area OSPF concepts and configurations, it is still the most complex routing protocol you
will use at the CCNA level. The exercises in the section focus on the conceptual framework of OSPF. It is
important to have a good grasp of these concepts before proceeding into the configuration of OSPF. The
following exercises build on each other and are best done in sequence.
Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
OSPF is a routing protocol developed for IP networks by the OSPF working group of the Internet
Engineering Task Force (IETF). OSPF has two primary characteristics. The first is that the protocol is an
open standard, which means that its specification is in the public domain, described in RFC 2328. The second
principal characteristic is that OSPF is based on the Dijkstra or SPF algorithm.
OSPF is a link-state routing protocol, whereas RIP and IGRP are distance vector routing protocols.
Routers that are running distance vector algorithms send all or a portion of their routing tables in routingupdate
messages to their neighbors.

The term link simply refers to the interface on a router and its relationship to its neighboring routers. The
collection all of these states forms the link-state database, which is an overall picture of networks in relation
to routers.
The ability of OSPF to separate a large internetwork into multiple areas is also referred to as hierarchical
routing. Routing still occurs between areas, but recalculating databases can be isolated to the area where
the change occurred.
The SPF algorithm is used to calculate the cost of links. The OSPF cost of an interface is inversely proportional
to the bandwidth of that interface, so a higher bandwidth indicates a lower cost. The default formula
used to calculate OSPF cost is
cost = 100,000,000/bandwidth in bps
The SPF algorithm calculates a loop-free topology using the node (or local router) as the starting point and
examining, in turn, information it has about adjacent nodes.
Build the SPF Loop-Free Topology
A physical topology is shown in Figure 2-1. All seven routers are running OSPF in the same single area
network. The OSPF cost value has been simplified for this exercise. Each link is labeled with its cost. Each
router will use the SPF algorithm to construct a loop-free topology with the local router as the root. In the
space provided or on a separate sheet of paper, draw the logical spanning-tree topology for each router.
(Hint: Use a pencil. You will make mistakes.)
Figure 2-1 Build the SPF Loop-Free Topology
D
A
B DC
3
1 4
1
4 1
2 1
1
F G
Chapter 2: Single-Area OSPF 103
Example: The following describes how you would draw the spanning-tree topology in Figure 2-1a showing
Router A as the local or root router. Start by drawing router A at the top. Router A can send traffic to
both router B and router C. You can see that router A will always send traffic destined for router B directly
to router B, so draw router B and connect it to router A. Label the link with the cost, which is 1. But will
router A send traffic destined for router C directly to router C? No. The cost of 4 is too high compared to
the path through router B, which has a cumulative cost of only 2. So, attach router C to router B and label
the link with its cost. Now, how would router A send traffic to router D? It would send it to router B,
which would forward the traffic directly to router D because the cumulative cost of 4 is lower than the
cumulative cost to forward the traffic to router C. So, attach router D to router B and label the link with its
cost. Now router B has three routers attached to it. Continue adding routers. Router E would receive traffic
from router A via router C. Both router F and router G would receive traffic from router A via router E.
E
2

104 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 2-1a Loop-free Topology for Router A
Figure 2-1b Loop-free Topology for Router B
Figure 2-1c Loop-free Topology for Router C
A D
2
1
1
A
B
C D
1
E F
1
1
1
B
3
G
A C
D
2
E
1 1
F G
C
1 2
B DE
1 3 1 1
3
F G

Figure 2-1d Loop-free Topology for Router D
A C
Figure 2-1e Loop-free Topology for Router E
Figure 2-1f Loop-free Topology for Router F
D
3 2
B DF
1 1 1 1
2
E
B D
E G
C F GD
A
1
1 2
1
2
F
D E GD
C
B
1
2
1
1
A
1
1
Chapter 2: Single-Area OSPF 105

106 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 2-1g Loop-free Topology for Router G
Concept Questions
What is the formula Cisco IOS uses to calculate the cost metric for OSPF?
Cost = 10 8 /bandwidth in bps
What is the OSPF cost of a T1 link?
10 8 /1544000 bps = 64.7, which is rounded to a cost of 64 by the IOS
What is the OSPF cost of a Fast Ethernet link?
10 8 /100,000,000 bps = 1
What is the OSPF cost of a 56-kps dialup link?
10 8 /56000 = 1785.71, which is rounded to a cost of 1785 by the IOS
The routers within an OSPF area have converged. What can you safely assume about the link-state databases
of all the routers within the area?
The link-state databases within an OSPF area are identical. That is, each router contains the same list of
links. In fact, this condition must be met before the routers within the area can calculate the SPF algorithm.
Name at least three advantages of OSPF that relate to its hierarchical routing characteristic.
Because OSPF is built on a multiple-area concept within autonomous systems, it has the following benefits:
■ Reduced frequency of SPF calculations
■ Smaller routing tables
■ Reduced link-state update overhead
Single-Area OSPF Configuration
C
G
1 1
E DF
B
2
1
1
A
Now that you have a good understanding of how OSPF works, it is time to learn the configuration commands
that you use in a single-area OSPF network. The first exercise in this section takes you step-by-step
through an OSPF configuration. The second exercise focuses on a topic that often causes problems for students:
the DR/BDR election. The final exercise is a journal entry. These exercises build on each other and
are best done in sequence.
D
2

Learn the OSPF Commands Exercise
1. Document the command syntax, including router prompt, to configure the OSPF routing process.
Router(config)#router ospf process-id.
2. The value for process-id can be any number between 1 and 65535.
3. True or False: All routers in an area must have the same process-id.
False. The process-id is only significant to the local router and has no meaning to other OSPF neighbors.
OSPF neighbors are unaware of what process ID the local router is using.
4. The command syntax, including router prompt, for adding network statements to the OSPF routing
process is
Router(config-router)#network address wildcard-mask area area-id.
5. For single area OSPF configurations, the area-id should always be 0.
6. The wildcard-mask argument works the same way as wildcard masks in access control list statements.
List the corresponding wildcard mask for each of the following subnet masks:
255.255.255.0 0.0.0.255
255.255.255.128 0.0.0.127
255.255.255.192 0.0.0.63
255.255.255.240 0.0.0.15
255.255.0.0 0.0.255.255
255.255.252.0 0.0.3.255
255.255.240.0 0.0.15.255
255.0.0.0 0.255.255.255
255.224.0.0 0.31.255.255
255.248.0.0 0.7.255.255
7. Refer to Figure 2-2. In the space provided, document the correct commands, including router prompt,
to configure RTA to advertise all directly connected networks in OSPF.
Figure 2-2 RTA OSPF Configuration
192.168.1.0/26
RTA
192.168.1.252/30 192.168.1.244/30
Chapter 2: Single-Area OSPF 107

108 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
RTA(config)#router ospf 1
RTA(config-router)#network 192.168.1.0 0.0.0.63 area 0
RTA(config-router)#network 192.168.1.244 0.0.0.3 area 0
RTA(config-router)#network 192.168.1.252 0.0.0.3 area 0
8. OSPF routers that share a common link become neighbors on that link. In Figure 2-3, RTB and RTC
are neighbors of RTA, but not of each other. These routers send each other OSPF Hello packets to
establish adjacency. These packets also act as keepalives so that each router knows that adjacent
routers are still functional.
Figure 2-3 Establishing OSPF Adjacency
192.168.1.128/26
9. Using Figure 2-3, document the correct commands, including router prompt, to configure RTB and
RTC to advertise all directly connected networks in OSPF.
!OSPF Configuration for RTB.
!Note that the process-id does NOT have to match with RTA
RTB(config)#router ospf 2
RTB(config-router)#network 192.168.1.64 0.0.0.63 area 0
RTB(config-router)#network 192.168.1.244 0.0.0.3 area 0
!OSPF Configuration for RTB.
RTC(config)#router ospf 3
192.168.1.0/26
RTC RTB
RTC(config-router)#network 192.168.1.128 0.0.0.63 area 0
RTC(config-router)#network 192.168.1.252 0.0.0.3 area 0
Note: Now is a good time to complete Curriculum Lab 2-1: Configuring the OSPF Routing Process (2.3.1).
RTA
192.168.1.252/30 192.168.1.244/30
OSPF
Area 0
192.168.1.64/26
10. On multiaccess networks (networks supporting more than two routers) such as Ethernet and Frame-
Relay networks, the Hello protocol elects a designated router (DR) and a backup designated router
(BDR). Among other things, the designated router is responsible for generating LSAs for the entire
multiaccess network, which reduces both routing-update traffic and management of link-state synchronization.

11. The DR/BDR election is based on OSPF priority and OSPF Router ID. By default, all OSPF routers
have a priority of 1. If all OSPF routers have the same priority, the highest Router ID determines the
DR and BDR.
12. Unless a loopback interface is configured, the highest IP address on an active interface at the moment
of OSPF process startup is used as the router ID.
13. In Figure 2-4, label each router with its router ID. Assume that all routers came up simultaneously and
that all interfaces are active.
Figure 2-4 Determine the Router ID
14. In Figure 2-4, which router would be the DR? RTC BDR? RTB
15. You can override the Router ID that OSPF chooses by configuring an IP address on a loopback interface.
This will provide stability to your OSPF network, because loopback interfaces do not become
inactive.
16. The syntax for configuring a loopback interface with an IP address is
Router(config)#interface loopback number
Router(config-if)#ip address address subnet-mask
17. Assume that network policy has determined that RTA is best suited to be the DR. In addition, the policy
states that all OSPF routers will be configured with a loopback interface, as follows, to provide stability
to OSPF:
■ 10.0.0.3/32 for RTA
■ 10.0.0.2/32 for RTB
■ 10.0.0.1/32 for RTC
Router ID: 192.168.1.65
Fa0/1 192.168.1.65/26
RTA
Fa0/0 192.168.1.3/29
OSPF
Area 0
Chapter 2: Single-Area OSPF 109
Fa0/1 192.168.1.193/26 Fa0/1 192.168.1.129/26
Fa0/0 192.168.1.1/29 Fa0/0 192.168.1.2/29
RTC
RTB
Router ID: 192.168.1.193 Router ID: 192.168.1.129

110 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
18. Document the correct commands, including router prompt, to configure loopback interfaces on each
router.
RTA(config)#interface loopback 0
RTA(config-if)#ip address 10.0.0.3 255.255.255.255
RTB(config)#interface loopback 0
RTB(config-if)#ip address 10.0.0.2 255.255.255.255
RTC(config)#interface loopback 0
RTC(config-if)#ip address 10.0.0.1 255.255.255.255
19. With loopback interfaces now configured on each router, what must you do to change which router
is DR?
Does the first sentence mean, “Either the routers must be reloaded or the OSPF process must be
removed with the no router ospf process-id command and then completely reconfigured before routers
will use the loopback addresses as the router ID”? However, the first router reconfigured will become
the DR regardless of the value of Router ID unless you reload the routers. So, the best way to ensure
which router is DR is by configuring priority.
Note: Now is a good time to complete Curriculum Lab 2-2: Configuring OSPF with Loopback Addresses (2.3.2).
20. In addition to configuring loopbacks, it would be a good idea to configure RTA with an OSPF priority
that ensures that it always wins the DR/BDR election. The syntax for configuring OSPF priority is
Router(config-if)#ip ospf priority priority
21. Document the commands you would configure on RTA to make sure its priority always wins the
DR/BDR election.
RTA(config)#interface Fa 0/0
RTA(config-if)#ip ospf priority 2
!Any priority higher than the default of 1 will work.
22. In Figure 2-5, note the differences in bandwidth. If OSPF uses the default bandwidth on the serial
interfaces to calculate the cost, RTB will send traffic destined for the LAN on RTC directly to RTC,
and RTC will send traffic destined for the LAN on RTB directly to RTB. However, the path through
RTA is faster. There are two ways to force RTB and RTC to send traffic to RTA. Explain the two different
ways to configure the correct cost. In what situations would one be better than the other?
Figure 2-5 Configure OSPF Cost Metric
192.168.1.0/26
Fa0/0
RTA
192.168.1.252/30 192.168.1.244/30
T1
S0/0
OSPF
Area 0
S0/1
DCE
192.168.1.128/26
S0/0
DCE
S0/1 192.168.1.64/26
Fa0/0
RTC
S0/1
192.168.1.248/30
386 kps
S0/0
DCE
RTB
Fa0/0
T1

The Cisco IOS uses the 10 8 /bps formula to assign a value for OSPF cost. However, this formula is
arbitrary and is not universal. The OSPF standard does not specify how cost is to be calculated. In
fact, it states, “This cost is configurable by the system administrator” (see RFC 2328, page 17).
Therefore, if you are configuring OSPF in a multivendor environment, you need to configure the cost
for the interface so that it matches the non-Cisco device. For that situation, it is best to use the ip ospf
cost bps command.
If, however, you are using all Cisco equipment, it is much more effective and simple to configure the
interface with the actual bandwidth by using the bandwidth bps command.
23. RTB and RTC are both Cisco 2600 series routers. The default bandwidth on serial interfaces for 2600
routers is 1544 kbps (T1). What command would you enter to verify the default or configured bandwidth
on an interface? show interface Referring to Figure 2-5, document the commands needed to
configure the bandwidth correctly so that OSPF uses an accurate cost metric.
RTB(config)#interface serial 0/0
RTB(config-if)#bandwidth 386
RTC(config)#interface serial 0/1
RTC(config-if)#bandwidth 386
Note: Now is a good time to complete Curriculum Lab 2-3: Modifying OSPF Cost Metric (2.3.3).
24. By default, a router trusts that information arriving from another router is “believable.” However, to
avoid malicious or inadvertent misinformation, you should configure authentication. The Cisco IOS
has two methods for authenticating OSPF routing updates: simple authentication and encrypted
authentication. With simple authentication, passwords are sent in clear text, affording no protection
from sniffer programs. Document the command syntax, including router prompt, to configure simple
authentication (two commands).
!On the interface that will participate in authentication:
Router(config-if)#ip ospf authentication-key password
!Within the OSPF router process:
Router(config-router)#area area-number authentication
25. You should use encrypted authentication whenever possible. Document the command syntax, including
router prompt, to configure encrypted authentication (two commands).
!On the interface that will participate in encryption:
Router(config-if)#ip ospf message-digest-key key-id encryption-type md5 key
!Within the OSPF router process:
Router(config-router)#area area-id authentication message-digest
26. Document the commands necessary to configure encrypted authentication of OSPF routing updates
for the routers in Figure 2-5. Because the commands are the same for all three routers, it is only necessary
that you document the commands for RTA. Use “allrouters” as the key.
RTA(config)#interface serial 0/0
RTA(config-if)#ip ospf message-digest-key 1 md5 7 allrouters
RTA(config)#interface serial 0/1
RTA(config-if)#ip ospf message-digest-key 1 md5 7 allrouters
RTA(config-if)#router ospf 1
RTA(config-router)#area 0 authentication message-digest
Chapter 2: Single-Area OSPF 111
Instructor Note: The preceding configuration also ensures that potentially malicious routing updates received on the
Fast Ethernet interfaces will not be believed. Authentication has been enabled for the entire area.

112 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Note: Now is a good time to complete Curriculum Lab 2-4: Configuring OSPF Authentication (2.3.4).
27. The DR, BDR, and every other router in an OSPF network sends out Hellos using 224.0.0.5 as the
destination address. If a DRother (a router that is not the DR) needs to send an LSA, it will send it
using 224.0.0.6 as the destination address. The DR and the BDR will receive LSAs at this address.
28. Complete the following table by listing the four types of OSPF networks and whether they have a
DR/BDR election.
Network Type Characteristics DR/BDR
Election?
Broadcast multiaccess Ethernet, Token Ring, or FDDI Yes
Non-broadcast multiaccess Frame Relay, X.25, SMDS Yes
Point-to-point PPP, HDLC No
Point-to-multipoint Configured by an administrator No
29. OSPF routers must use matching Hello intervals and Dead intervals on the same link. These are used
to time the exchange of link-state information as well as to determine when a link is down.
30. On broadcast OSPF networks, the default Hello interval is 10 seconds and the default Dead interval is
40 seconds. On nonbroadcast networks, the default Hello interval is 30 seconds and the default Dead
interval is 120 seconds.
31. These default interval values result in efficient OSPF operation and seldom need to be modified.
However, you can change them. Document the command syntax, including router prompt, to change
these values.
Router(config-if)#ip ospf hello-interval seconds
Router(config-if)#ip ospf dead-interval seconds
32. Again, refer to Figure 2-5. Assuming that the current intervals are 10 and 40, document the commands
necessary to change these intervals on the link between RTB and RTC to a value four times greater
than the current value.
RTB(config)#interface serial 0/0
RTB(config-if)#ip ospf hello-interval 40
RTB(config-if)#ip ospf dead-interval 160
RTC(config)#interface serial 0/1
RTC(config-if)#ip ospf hello-interval 40
RTC(config-if)#ip ospf dead-interval 160
Instructor Note: It is not necessary to configure the Dead interval as long as the desired interval is four times the
Hello interval. The IOS will automatically increase the Dead interval to four times the configured Hello interval.
Note: Now is a good time to complete Curriculum Lab 2-5: Configuring OSPF Timers (2.3.5).
33. Refer to Figure 2-6 for the remaining questions in this section. RTA is your gateway router because it
provides access outside the area. In OSPF terminology, RTA is called the Autonomous System
Boundary Router (ASBR) because it connects to an external routing domain that uses a different routing
policy.

Figure 2-6 Propagating a Default Route
192.168.1.128/26
Address Space
192.168.1.0/24
Fa0/0
RTA
S0/1
RTC 192.168.1.248/30 S0/0 RTB
DCE
34. Each routing protocol handles the propagation of default routing information a little differently. For
OSPF, the gateway router must be configured with two commands. First, RTA needs a static default
route (also known as the “quad-zero” route) pointing to ISP. Document the command syntax to configure
a static default route on RTA.
Router(config)#ip route 0.0.0.0 0.0.0.0 [interface | next-hop-address]
Instructor Note: Students should also know the difference between using the interface argument and using the nexthop-address
argument. When you configure the outbound interface, the router does not need to do the extra step of
looking up the next hop’s address in the routing table. Therefore, the interface argument has an administrative distance
of 0. This is also the preferred configuration if the next hop’s address changes often. If you configure the next-hopaddress
argument, the administrative distance is 1 to account for the extra processing time.
35. Using the interface argument, document the command necessary to configure RTA with a static
default route pointing to ISP.
RTA(config)#ip route 0.0.0.0 0.0.0.0 serial 1/0
36. At this point, RTA can send pings to ISP, and ISP will respond as long as the pings are sourced from
the serial 1/0 interface on RTA. However, any ping coming from the 192.168.1.0/24 address space will
be discarded by ISP. Why?
Because ISP does not yet have a route to the 192.168.1.0/24 address space.
37. Document the command syntax used to configure a static route.
Router(config)#ip route network_address subnet_mask [interface | next-hop-address]
38. Using the next-hop-address argument, document the command necessary to configure ISP with a static
route pointing to the 192.168.1.0/24 address space.
ISP(config)#ip route 192.168.1.0 255.255.255.0 209.165.201.2
39. At this point, any host on the LAN attached to RTA will be able to access ISP and ping the Public
Web Server at 209.165.202.129. However, RTB and RTC still cannot ping outside the 192.168.1.0/24
address space. Why?
Because neither router has a default route.
S1/0
209.165.201.2/30
192.168.1.252/30
RTA
Propagates
Default Route to
RTB and RTC
192.168.1.244/30
S0/0
DCE
S0/0
192.168.1.0/26
Fa0/0
S0/1
DCE
Default Route
209.165.201.1/30
Static Route
S0/1
Fa0/0
Chapter 2: Single-Area OSPF 113
S0/0
DCE
ISP
OSPF
Area 0 192.168.1.64/26
Public Web Server
209.165.202.129/30

114 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
40. Document the command that needs to be configured on RTA to fix this problem.
RTA(config-router)#default-information originate
Note: Now is a good time to complete Curriculum Lab 2-6: Propagating Default Routes in an OSPF Domain (2.3.6).
DR/BDR Election Exercise
In the following exercises, assume that all routers are simultaneously booted. Determine the network type,
if applicable, and label which router is elected as the DR and which router is elected as the BDR.
Hint: Remember, if priority is equal, router ID determines DR and BDR.
Refer to Figure 2-7 and answer the following questions:
Figure 2-7 DR/BDR Election Exercise 1 Topology
E0 = 172.16.1.1
L0 = 192.168.1.4
RTA
What is the router ID for RTA? 192.168.1.4
What is the router ID for RTB? 192.168.1.3
What is the router ID for RTC? 192.168.1.2
What is the router ID for RTD? 192.168.1.1
Which router will be elected DR? RTA
Which router will be elected BDR? RTB
RTC
E0 = 172.16.1.3
S0 = 192.168.5.1
L0 = 192.168.1.2
Refer to Figure 2-8 and determine whether there will be a DR/BDR election. If applicable, designate
which router is DR and which router is BDR.
Figure 2-8 DR/BDR Election Exercise 2 Topology
E0 = 172.16.1.2
L0 = 192.168.1.3
RTB
The loopback address is the router ID in every case
172.15.1.2/30
S0
Fa0
172.16.1.2/24
Router ID
172.15.1.1/30
S0
Fa1
172.16.1.1/24
RTA
Router ID
172.18.1.2/30
S1
Fa0
172.17.1.1/24
Router ID
RTD
E0 = 172.16.1.4
S0 = 192.168.5.2
L0 = 192.168.1.1
Router ID
172.18.1.1/30
S0
RTD RTB
RTC
Fa0
172.17.1.2/24

Network DR/BDR Election? Which Router Is the DR? Which Router Is the BDR?
172.15.1.0/30 No — —
172.16.1.0/24 Yes RTC RTD
172.17.1.0/24 Yes RTB RTC
172.18.1.0/30 No — —
Refer to Figure 2-9 and answer the following questions:
Figure 2-9 DR/BDR Election Exercise 3 Topology
What is the router ID for RTA? 209.165.201.2
What is the router ID for RTB? 192.168.1.2
What is the router ID for RTC? 10.1.1.1
Which router is DR for the 192.168.0.0/24 network? RTA
Which router is BDR for the 192.168.0.0/24 network? RTB
Assuming a priority of zero on RTA, which router is DR for the 192.168.1.0/24 network? RTB
What will happen if another router, RTD, joins the 192.168.1.0/24 network with a router ID of
209.165.201.9?
Nothing. Both the DR and BDR have to go down before RTD can become the DR.
Journal Entry
RTC
RTA
E0
E0 E0
S0
E0 = 192.168.0.3/24
S0 = 192.168.1.3/30
L0 = 10.1.1.1/32
Router ID
Router ID
E0 = 192.168.0.1/24
S0 = 209.165.201.2/30
S0
OSPF
Area 0
Chapter 2: Single-Area OSPF 115
S0 = 209.165.201.1/30
In a simple three-router topology, it may not be necessary to run OSPF as your routing protocol. Under
what circumstances would you choose to use OSPF instead of RIPv2?
Answers will vary. However, you are looking for an answer that takes into consideration the benefits and
limitations of both routing protocols. For example, RIP cannot make a decision about routing based on a
cost metric. RIP looks at hops and only hops to make its decision. In addition, some equipment may not
support RIPv2 but support OSPF.
S0
ISP
RTB
E0 = 192.168.0.2/24
S0 = 192.168.1.2/30
Router ID

116 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Lab Exercises
Command Reference
In the table that follows, record the command, including the correct router prompt, that fits the description.
Fill in any blanks with the appropriate missing information.
Command Description
Router(config)#router ospf 123 Turns on OSPF process number 123. The process ID is any
value between 1 and 65535. The process ID does not equal
the OSPF area.
Router(config-router)#network OSPF advertises interfaces, not networks. Uses the
172.16.10.0 0.0.0.255 area 0 wildcard mask to determine which interfaces to advertise.
The command shown reads: any interface with an address
of 172.16.10.x is to be put into area 0.
Router(config)#interface lo0 Creates the virtual interface loopback 0.
Router(config-if)#ip ospf priority 50 Changes the OSPF priority for an interface to 50.
Router(config-if)#bandwidth 128 Changes the bandwidth of an interface to 128 kbps.
Router(config-if)#ip ospf cost 1564 Changes the cost to a value of 1564.
Router(config-router)#area 0 authentication Turns on simple authentication within the OSPF routing
process.
Router(config-if)#ip ospf Sets the simple authentication key (password) to fred on an
authentication-key fred interface.
Router(config-router)#area 0 authentication Turns on MD5 authentication within the OSPF routing
message-digest process.
Router(config-if)#ip ospf message- Sets 1 as the key-id and fred as the key on an interface.
digest-key 1 md5 7 fred
or
Router(config-if)#ip ospf message-digest-key
1 md5 fred
Router(config-if)#ip ospf hello-interval 20 Changes the Hello Interval timer to 20 seconds.
Router(config-if)#ip ospf dead-interval 80 Changes the Dead Interval timer to 80 seconds.
Router(config)#ip route 0.0.0.0 0.0.0.0 s0/0 Creates a static default route pointing out the serial 0/0
interface. This route will have an administrative distance
of 0.
Router(config)#ip route Creates a static default route pointing to the next-hop IP
0.0.0.0 0.0.0.0 192.168.1.1 address of 192.168.1.1. This route will have an
administrative distance of 1.
Router(config-router)#default-information Sets the default route to be propagated to all OSPF routers.
originate
Router#show ip protocol Displays parameters for all routing protocols running on
the router.

Command Description
Router#show ip route Displays complete IP routing table.
Router#show ip ospf Displays basic OSPF information for all OSPF processes
running on the router.
Router#show ip ospf interface Displays OSPF information as it relates to all interfaces.
Router#show ip ospf neighbor List all the OSPF neighbors and their states.
Router#show ip ospf neighbor detail Displays a detailed list of neighbors.
Router#clear ip route * Clears entire routing table, forcing it to rebuild.
Router#clear ip ospf counters Resets OSPF counters.
Router#clear ip ospf process Resets entire OSPF process, forcing OSPF to re-create
neighbors, the database, and the routing table.
Router#debug ip ospf events Displays all OSPF events.
Router#debug ip ospf adj Displays the various OSPF states as neighbors form
adjacencies as well as the DR and BDR election between
adjacent routers.
Router#debug ip ospf packets Displays OSPF packets as they are sent and received.
Curriculum Lab 2-1: Configuring the OSPF Routing
Process (2.3.1)
Figure 2-10 Topology for Lab 2-1
Straight-Through Cable
Area 0
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable
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118 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 2-1 Lab Equipment Configuration
Router Designation Router Name Routing Protocol Network Statements
Router 1 BERLIN OSPF 192.168.1.128
192.168.15.0
Router 2 ROME OSPF 192.168.15.0
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 2-2 Lab Equipment Interface/IP Address Configurations
192.168.0.0
Router IP Host Fast Ethernet 0 Interface Type Serial 0 Address/
Designation Table Entry Address/Subnet Mask Serial 0 Subnet Mask
Router 1 ROME 192.168.1.129/26 DCE 192.168.15.1/30
Router 2 BERLIN 192.168.0.1/24 DTE 192.168.15.2/30
The interface type and address/subnet mask for the serial 1 interface on both routers is not applicable for
this lab.
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Set up an IP addressing scheme for OSPF area 0.
■ Configure and verify OSPF routing.
Background/Preparation
Cable a network that is similar to the one in Figure 2-10. You can use any router that meets the interface
requirements in Figure 2-10 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A, “Router Interface Summary Chart,” to correctly specify the interface identifiers
based on the equipment in your lab. The 1721 series routers produced the configuration output in
this lab. Another router might produce slightly different output. You should execute the following steps on
each router unless you are specifically instructed otherwise. Start a HyperTerminal session.
Implement the procedure documented in Appendix C, “Erasing and Reloading the Router,” before you
continue with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname as shown in Table 2-1. Then,
configure the console, virtual terminal, and enable passwords. Next, configure the interfaces according to
Table 2-2. Finally, configure the IP hostnames. Do not configure the routing protocol until you are specifically
told to. If you have problems configuring the router basics, refer to Lab 1-2, “Review of Basic Router
Configuring with RIP.”
Note: You may need to add the command ip subnet-zero because of the use of the ZERO subnet with VLSM on the
192.168.1.0/30 and 192.168.1.128/26 networks.

BERLIN
Router>enable
Router#configure terminal
Router(config)#hostname BERLIN
BERLIN(config)#enable secret class
BERLIN(config)#line console 0
BERLIN(config-line)#password cisco
BERLIN(config-line)#login
BERLIN(config-line)#line vty 0 4
BERLIN(config-line)#password cisco
BERLIN(config-line)#login
BERLIN(config-line)#exit
BERLIN(config)#interface serial 0
BERLIN(config-if)#ip address 192.168.15.1 255.255.255.252
BERLIN(config-if)#clock rate 64000
BERLIN(config-if)#no shutdown
BERLIN(config-if)#exit
BERLIN(config)#interface FastEthernet 0
BERLIN(config-if)#ip address 192.168.1.129 255.255.255.192
BERLIN(config-if)#no shutdown
BERLIN(config-if)#exit
BERLIN(config)#ip host ROME 192.168.0.1 192.168.15.2
ROME
Router>enable
Router#configure terminal
Router(config)#hostname ROME
ROME(config)#enable secret class
ROME(config)#line console 0
ROME(config-line)#password cisco
ROME(config-line)#login
ROME(config-line)#line vty 0 4
ROME(config-line)#password cisco
ROME(config-line)#login
ROME(config-line)#exit
ROME(config)#interface serial 0
ROME(config-if)#ip address 192.168.15.2 255.255.255.252
ROME(config-if)#no shutdown
ROME(config-if)#exit
ROME(config)#interface FastEthernet 0
ROME(config-if)#ip address 192.168.0.1 255.255.255.0
ROME(config-if)#no shutdown
ROME(config-if)#exit
ROME(config)#ip host BERLIN 192.168.1.129 192.168.15.1
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120 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
BERLIN#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Why save the running configuration to the startup configuration?
So that the router will keep the configuration when it is reset.
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Rome
IP address: 192.168.0.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.0.1
Host connected to router Berlin
IP address: 192.168.1.130
Subnet mask: 255.255.255.128
Default gateway: 192.168.1.129
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000,
check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks will demonstrate the process that is required to get communication working while using
OSPF as the routing protocol.
Task 4: View the Router’s Configuration and Interface Information
Step 1. At the privileged EXEC mode prompt, type the following:
BERLIN#show running-config
Step 2. Using the show ip interface brief command, check the status of each interface.
What is the state of the interfaces on each router?
BERLIN:
Fast Ethernet 0: Up
Serial 0: Up
Serial 1: Down
ROME:
Fast Ethernet 0: Up
Serial 0: Up
Serial 1: Down

Step 3. Ping from one of the connected serial interfaces to the other.
Was the ping successful? Yes
Step 4. If the ping was not successful, troubleshoot the router configuration until the ping is successful.
Instructor Note: If the ping is not successful, the show ip interface brief command would have indicated where the
problem was. The configured interfaces should be in the “up” and “up” state.
Task 5: Configure OSPF Routing on Router BERLIN
Step 1. Configure an OSPF routing process on router BERLIN. Use OSPF process number 1 and
ensure that all networks are in area 0.
BERLIN(config)#router ospf 1
BERLIN(config-router)#network 192.168.1.128 0.0.0.63 area 0
BERLIN(config-router)#network 192.168.15.0 0.0.0.3 area 0
BERLIN(config-router)#end
Step 2. Examine the routers that are running configuration files.
Did the IOS version automatically add any lines under router OSPF 1? Yes
If so, what did it add? log-adjacency-changes
Step 3. If there were no changes to the running configuration, type the following commands:
BERLIN(config)#router ospf 1
BERLIN(config-router)#log-adjacency-changes
BERLIN(config-router)#end
Step 4. Show the routing table for the BERLIN router.
BERLIN#show ip route
Do entries exist in the routing table? No
Why?
OSPF is not configured on ROME yet.
Task 6: Configure OSPF Routing on Router ROME
Step 1. Configure an OSPF routing process on router ROME. Use OSPF process number 1 and ensure
that all networks are in area 0.
ROME(config)#router ospf 1
ROME(config-router)#network 192.168.1.0 0.0.0.255 area 0
ROME(config-router)#network 192.168.15.0 0.0.0.3 area 0
ROME(config-router)#end
Step 2. Examine the ROME router running configuration files.
Did the IOS version automatically add lines under router OSPF 1? Yes
If so, what did it add? log-adjacency-changes
Step 3. If there were no changes to the running configuration, type the following commands:
ROME(config)#router ospf 2
ROME(config-router)#log-adjacency-changes
ROME(config-router)#end
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122 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 4. Show the routing table for the ROME router.
ROME#show ip route
Are there OSPF entries in the routing table now? Yes
What is the metric value of the OSPF route?
It varies; the default with bandwidth on serial set to 128 kbps gives a net cost of 782.
What is the VIA address in the OSPF route? 192.168.15.1
Are routes to all networks shown in the routing table? Yes
What does the O mean in the first column of the routing table?
The route was learned by OSPF.
Task 7: Test Network Connectivity
Ping the BERLIN host from the ROME host. Was it successful? Yes
If not, troubleshoot as necessary.
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.
Curriculum Lab 2-2: Configuring OSPF with Loopback
Addresses (2.3.2)
Figure 2-11 Topology for Lab 2-2
Router 1
Router 2
Router 3

Table 2-3 Lab Equipment Configuration: Part I
Router Router Routing OSPF Network
Designation Name Protocol Routing ID Statements
Router 1 London OSPF 1 192.168.1.0
Router 2 Ottawa OSPF 1 192.168.1.0
Router 3 Brasilia OSPF 1 192.168.1.0
The enable secret password for all routers is class.
The enable, VTY, and console passwords for each router is cisco.
Table 2-4 Lab Equipment Configuration: Part II
Router IP Host Fast Ethernet 0 Loopback Interface/
Designation Table Entry Address/Subnet Mask Subnet Mask
Router 1 Ottawa Brasilia 192.168.1.1/24 192.168.31.11/32
Router 2 London Brasilia 192.168.1.2/24 192.168.31.22/32
Router 3 London Ottawa 192.168.1.3/24 192.168.31.33/32
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Configure routers with a Class C IP addressing scheme.
■ Observe the election process for designated routers (DR) and backup designated routers (BDR) on the
multiaccess network.
■ Configure loopback addresses for OSPF stability.
■ Assign each OSPF interface a priority to force the election of a specific router as DR.
Background/Preparation
Cable a network that is similar to the one in Figure 2-11. You can use any router that meets the interface
requirements in Figure 2-11 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise. Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before continuing with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname as shown in Table 2-3. Then,
configure the console, virtual terminal, and enable passwords. Next, configure the interfaces and the IP
hostnames according to the Lab Equipment Configuration tables, Tables 2-3 and 2-4. If you have problems
configuring the router basics, refer to Lab 1-2, “Review of Basic Router Configuring with RIP.”
Note: Do not configure loopback interfaces and routing protocols yet.
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124 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
LONDON
Router>enable
Router#configure terminal
Router(config)#hostname LONDON
LONDON(config)#enable secret class
LONDON(config)#line console 0
LONDON(config-line)#password cisco
LONDON(config-line)#login
LONDON(config-line)#line vty 0 4
LONDON(config-line)#password cisco
LONDON(config-line)#login
LONDON(config-line)#exit
LONDON(config)#interface fastethernet 0/0
LONDON(config-if)#ip address 192.168.1.1 255.255.255.0
LONDON(config-if)#no shutdown
LONDON(config-if)#exit
LONDON(config)#ip host OTTAWA 192.168.1.2
LONDON(config)#ip host BRASILIA 192.168.1.3
OTTOWA
Router>enable
Router#configure terminal
Router(config)#hostname OTTAWA
OTTOWA(config)#enable secret class
OTTOWA(config)#line console 0
OTTOWA(config-line)#password cisco
OTTOWA(config-line)#login
OTTOWA(config-line)#line vty 0 4
OTTOWA(config-line)#password cisco
OTTOWA(config-line)#login
OTTOWA(config-line)#exit
OTTOWA(config)#interface fastethernet 0/0
OTTOWA(config-if)#ip address 192.168.1.2 255.255.255.0
OTTOWA(config-if)#no shutdown
OTTOWA(config-if)#exit
OTTOWA(config)#ip host LONDON 192.168.1.1
OTTOWA(config)#ip host BRASILIA 192.168.1.3
BRASILIA
Router>enable
Router#configure terminal
Router(config)#hostname BRASILIA
BRASILIA(config)#enable secret class
BRASILIA(config)#line console 0
BRASILIA(config-line)#password cisco

BRASILIA(config-line)#login
BRASILIA(config-line)#line vty 0 4
BRASILIA(config-line)#password cisco
BRASILIA(config-line)#login
BRASILIA(config-line)#exit
BRASILIA(config)#interface fastethernet 0/0
BRASILIA(config-if)#ip address 192.168.0.1 255.255.255.0
BRASILIA(config-if)#no shutdown
BRASILIA(config-if)#exit
BRASILIA(config)#ip host LONDON 192.168.1.1
BRASILIA(config)#ip host OTTAWA 192.168.1.2
Task 2: Save the Configuration Information for All the Routers
Why should you save the running configuration to the startup configuration?
So that the router will keep the configuration when it is reset.
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host with gateway London
IP address: 192.168.1.4
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Host with gateway Ottawa
IP address: 192.168.1.5
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.2
Host with gateway Brasilia
IP address: 192.168.1.6
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.3
Chapter 2: Single-Area OSPF 125
Step 2. Each workstation should be able to ping all the attached routers, because they are all part of the
same subnetwork. Troubleshoot as necessary. Hint: Remember to assign a specific IP address
and default gateway to the workstation. If you are running Windows 98, check using Start >
Run > winipcfg. If you are running Windows 2000, check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process required to get communication working by using OSPF as the
routing protocol.

126 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 4: View the Router’s Configuration and Interface Information
Step 1. At the privileged EXEC mode prompt, type show running-config.
Step 2. Using the show ip interface brief command, check the status of each interface.
What is the state of the interfaces on each router?
London:
■ Fast Ethernet 0: Up
■ Serial 0: Down
■ Serial 1: Down
Ottawa:
■ Fast Ethernet 0: Up
■ Serial 0: Down
■ Serial 1: Down
Brasilia:
■ Fast Ethernet 0: Up
■ Serial 0: Down
■ Serial 1: Down
Task 5: Verify Connectivity of the Routers
Ping all the connected Fast Ethernet interfaces from each other.
Were the pings successful? Yes
If the pings were not successful, troubleshoot the router configuration until the ping is successful.
Task 6: Configure OSPF Routing on Router London
Step 1. Configure an OSPF routing process on router London. Use OSPF process number 1 and ensure
that all networks are in area 0.
London(config)#router ospf 1
London(config-router)#network 192.168.1.0 0.0.0.255 area 0
London(config-router)#end
Step 2. Examine the London router running the configuration file.
Did the IOS version automatically add lines under router OSPF 1? Yes/No
Instructor Note: The log-adjacency-changes command is added automatically with newer versions of the IOS.
Step 3. If there were no changes to the running configuration, type the following commands:
London(config)#router ospf 1
London(config-router)#log-adjacency-changes
London(config-router)#end
Step 4. Show the routing table for the London router:
London#show ip route

Are entries in the routing table? No
Why?
No other routers have been configured with OSPF.
Task 7: Configure OSPF Routing on Router Ottawa
Step 1. Configure an OSPF routing process on router Ottawa. Use OSPF process number 1 and ensure
that all networks are in area 0.
Ottawa(config)#router ospf 1
Ottawa(config-router)#network 192.168.1.0 0.0.0.255 area 0
Ottawa(config-router)#end
Step 2. Examine the Ottawa router running configuration files.
Did the IOS version automatically add lines under router OSPF 1? Yes/No
Step 3. If no changes were made to the running configuration, type the following commands:
Ottawa(config)#router ospf 1
Ottawa(config-router)#log-adjacency-changes
Ottawa(config-router)#end
Task 8: Configure OSPF Routing on Router Brasilia
Step 1. Configure an OSPF routing process on router Brasilia. Use OSPF process number 1 and ensure
that all networks are in area 0.
Brasilia(config)#router ospf 1
Brasilia(config-router)#network 192.168.1.0 0.0.0.255 area 0
Brasilia(config-router)#end
Step 2. Examine the Brasilia router running configuration files.
Did the IOS version automatically add lines under router OSPF 1? Yes
What did it add? log-adjacency-changes
Step 3. If there were no changes to the running configuration, type the following commands:
Brasilia(config)#router ospf 1
Brasilia(config-router)#log-adjacency-changes
Brasilia(config-router)#end
Task 9: Test Network Connectivity
Ping the Brasilia router from the London router. Was it successful? Yes
If not, troubleshoot as necessary.
Task 10: Show OSPF Adjacencies
Type the command show ip ospf neighbor on all routers to verify that the OSPF routing has formed adjacencies.
Is there a designated router identified? Yes
Is there a backup designated router? Yes
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128 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Type the command show ip ospf neighbor detail for more information.
What is the neighbor priority of 192.168.1.1 from router Brasilia? 1
What interface is identified as being part of area 0? FastEthernet 0/0
Task 11: Configure the Loopback Interfaces
Configure the loopback interface on each router to allow for an interface that will not go down due to network
change or failure. You can accomplish this by typing interface loopback # at the global configuration
mode prompt, where the # represents the number of the loopback interface from 0 to 2,147,483,647.
London(config)#interface loopback 0
London(config-if)#ip address 192.168.31.11 255.255.255.255
London(config-router)#end
Ottawa(config)#interface loopback 0
Ottawa(config-if)#ip address 192.168.31.22 255.255.255.255
Ottawa(config-router)#end
Brasilia(config)#interface loopback 0
Brasilia(config-if)#ip address 192.168.31.33 255.255.255.255
Brasilia(config-router)#end
Task 12: Save the Configuration Information for All the Routers
After you save the configurations on all the routers, power them down and back up again.
Task 13: Show OSPF Adjacencies
Step 1. Type the command show ip ospf neighbor on all routers to verify that the OSPF routing has
formed adjacencies.
Is a designated router identified? Yes
What are the Router ID and link address of the DR?
192.168.31.33 and 192.168.1.3
Is there a backup designated router? Yes
What are the Router ID and link address of the BDR?
192.168.31.22 and 192.168.1.2
What is the third router referred to as? DROTHER
What is that router’s ID and link address?
192.168.31.11 and 192.168.1.1
Step 2. Type the command show ip ospf neighbor detail for more information.
What is the neighbor priority of 192.168.1.1 from router Brasilia? 1
Which interface is identified as being part of area 0? FastEthernet0/0

Task 14: Verify OSPF Interface Configuration
Type show ip ospf interface fastethernet 0 on the London router.
What is the OSPF state of the interface? DROTHER
What is the default priority of the interface? 1
What is the network type of the interface? Broadcast
Task 15: Configure London to Always Be the DR
Step 1. To ensure that the London router always becomes the DR for this multiaccess segment, you
must set the OSPF priority. London is the most powerful router in the network, so it is best
suited to become the DR. Giving London’s loopback a higher IP address is not advised because
the numbering system has advantages for troubleshooting. Also, London is not to act as the DR
for all segments to which it might belong.
Step 2. Set the priority of the interface to 50 on the London router only.
London(config)#interface fastethernet 0/0
London(config-if)#ip ospf priority 50
London(config-router)#end
Step 3. Display the priority for interface FastEthernet 0/0.
London#show ip ospf interface fastethernet 0/0
Task 16: Watch the Election Process
To watch the OSPF election process, restart all the routers. As soon as the router prompt is available, type
the following:
Ottawa>enable
Ottawa#debug ip ospf events
Which router was elected DR? London
Which router was elected BDR? Brasilia
Why?
It has the higher priority.
To turn off all debugging, type undebug all.
Task 17: Show OSPF Adjacencies
Type the command show ip ospf neighbor on the Ottawa router to verify that the OSPF routing has
formed adjacencies.
What is the priority of the DR? 50
Chapter 2: Single-Area OSPF 129
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.

130 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 2-3: Modifying OSPF Cost Metric (2.3.3)
Figure 2-12 Topology for Lab 2-3
Straight-Through Cable
Table 2-5 Lab Equipment Configuration: Part I
Router Designation Router Name Routing Protocol Network Statements
Router 1 Cairo OSPF 192.168.1.0
Router 2 Moscow OSPF 192.168.1.0
192.168.0.0
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 2-6 Lab Equipment Configuration: Part II
Area 0
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable
Router IP Host Fast Ethernet 0 Interface Type Serial 0 Address/
Designation Table Entry Address/Subnet Mask Serial 0 Subnet Mask
Router 1 Moscow 192.168.1.129/26 DCE 192.168.1.1/30
Router 2 Cairo 192.168.0.1/24 DTE 192.168.1.2/30
The interface type and address/subnet mask for the serial 1 interface on both routers are not applicable for
this lab.
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.

Objectives
■ Set up an IP addressing scheme for the OSPF area.
■ Configure and verify OSPF routing.
■ Modify the OSPF cost metric on an interface.
Background/Preparation
Cable a network that is similar to the one in Figure 2-12. You can use any router that meets the interface
requirements in Figure 2-12 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, enter the global configuration mode and configure the hostname, console, virtual terminal,
and enable passwords. Next, configure the interfaces and IP hostnames according to the Lab Equipment
Configuration tables, Tables 2-5 and 2-6. If you have problems configuring the router basics, refer to Lab
1-2, “Review of Basic Router Configuring with RIP.”
Note: You may need to add the command ip subnet-zero because of the use of the ZERO subnet with VLSM on the
192.168.1.0/30 and 192.168.1.128/26 networks.
Note: Do not configure the routing protocol until you are specifically told to.
Cairo
Router>enable
Router#configure terminal
Router(config)#hostname Cairo
Cairo(config)#enable secret class
Cairo(config)#line console 0
Cairo(config-line)#password cisco
Cairo(config-line)#login
Cairo(config-line)#line vty 0 4
Cairo(config-line)#password cisco
Cairo(config-line)#login
Cairo(config-line)#exit
Cairo(config)#interface serial 0/0
Cairo(config-if)#ip address 192.168.1.1 255.255.255.252
Cairo(config-if)#clockrate 64000
Cairo(config-if)#no shutdown
Cairo(config-if)#interface fastethernet 0/0
Cairo(config-if)#ip address 192.168.1.129 255.255.255.128
Cairo(config-if)#no shutdown
Cairo(config-if)#exit
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132 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Cairo(config)#ip host Moscow 192.168.0.1 192.168.1.2
Cairo(config)#exit
Moscow
Router>enable
Router#configure terminal
Router(config)#hostname Moscow
Moscow(config)#enable password cisco
Moscow(config)#enable secret class
Moscow(config)#line console 0
Moscow(config-line)#password cisco
Moscow(config-line)#login
Moscow(config-line)#line vty 0 4
Moscow(config-line)#password cisco
Moscow(config-line)#login
Moscow(config-line)#exit
Moscow(config)#interface serial 0/0
Moscow(config-if)#ip address 192.168.1.2 255.255.255.252
Moscow(config-if)#no shutdown
Moscow(config-if)#interface fastethernet 0/0
Moscow(config-if)#ip address 192.168.0.1 255.255.255.0
Moscow(config-if)#no shutdown
Moscow(config-if)#exit
Moscow(config)#ip host Cairo 192.168.1.129 192.168.1.1
Moscow(config)#exit
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
Cairo#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Moscow#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Why should you save the running configuration to the startup configuration?
Saving the configuration will allow the router to keep the configuration after a reload or power down.
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Cairo
IP address: 192.168.1.130
Subnet mask: 255.255.255.192
Default gateway: 192.168.1.129
Host connected to router Moscow
IP address: 192.168.0.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.0.1

Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000,
check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process that is required to get communication working while using OSPF
as the routing protocol.
Task 4: View the Router’s Configuration and Interface Information
Step 1. At the privileged EXEC mode prompt, type the following:
Cairo#show running-config
[…]
hostname Cairo
!
enable secret 5 $1$hGOQ$I7bGdq5INLFy2ZT4.5CdY/
enable password cisco
!
ip subnet-zero
!
interface FastEthernet0/0
ip address 192.168.1.129 255.255.255.192
speed auto
!
interface Serial0/0
ip address 192.168.1.1 255.255.255.252
clockrate 64000
!
interface Serial1/0
no ip address
shutdown
!
ip classless
no ip http server
!
!
line con 0
password cisco
login
line aux 0
line vty 0 4
password cisco
login
!
no scheduler allocate
end
Step 2. Using the show ip interface brief command, check the status of each interface.
What is the state of the interfaces on each router?
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134 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Cairo:
■ Fast Ethernet 0: Up
■ Serial 0: Up
Moscow:
■ Fast Ethernet 0: Up
■ Serial 0: Up
Step 3. Ping from one of the connected router serial interfaces to the other.
Was the ping successful? Yes
If the ping was not successful, troubleshoot the router configuration until the ping is successful.
Task 5: Configure OSPF Routing on Router Cairo
Step 1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks
are in area 0.
Cairo(config)#router ospf 1
Cairo(config-router)#network 192.168.1.128 0.0.0.63 area 0
Cairo(config-router)#network 192.168.1.0 0.0.0.3 area 0
Cairo(config-router)#end
Step 2. Examine the running configuration file.
Did the IOS version automatically add lines under router OSPF 1? Yes
What did it add? log-adjacency-changes
Step 3. If there were no changes to the running configuration, type the following commands:
Cairo(config)#router ospf 1
Cairo(config-router)#log-adjacency-changes
Cairo(config-router)#end
Step 4. Show the routing table for the Cairo router.
Cairo#show ip route
Do entries exist in the routing table? No
Why?
Other routers have not been configured to send out OSPF updates yet.
Task 6: Configure OSPF Routing on the Moscow Router
Step 1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks
are in area 0.
Moscow(config)#router ospf 1
Moscow(config-router)#network 192.168.0 .0 0.0.0.255 area 0
Moscow(config-router)#network 192.168.1.0 0.0.0.3 area 0
Moscow(config-router)#end

Step 2. Examine the running configuration file.
Did the IOS version automatically add lines under router OSPF 1? Yes
Step 3. If there were no changes to the running configuration, type the following commands:
Moscow(config)#router ospf 1
Moscow(config-router)#log-adjacency-changes
Moscow(config-router)#end
Task 7: Show the Routing Table Entries
Show the routing table entries for the Cairo router.
Cairo#show ip route
Does the routing table have OSPF entries now? Yes
What is the metric value of the OSPF route? 110
What is the VIA address in the OSPF route? 192.168.1.2
Are routes to all networks shown in the routing table? Yes
What does the O mean in the first column of the routing table?
The route was learned by OSPF.
Task 8: Test Network Connectivity
Ping the Cairo host from the Moscow host. Was it successful? Yes
If not, troubleshoot as necessary.
Task 9: Look at the OSPF Cost on the Cairo Router Interfaces
Show the properties of the Cairo router serial and Fast Ethernet interfaces by using the show interfaces
command.
What is the default bandwidth of the interfaces?
■ Serial interface: BW 1544 kbps
■ Fast Ethernet interface: BW 100000 kbps
Calculate the OSPF cost.
■ Serial interface: 64
■ Fast Ethernet interface: 1
Table 2-7 OSPF Cost Calculations for Common Link Types
Link Bandwidth Default OSPF Cost
56 kbps 1785
T1 64
10-Mbps Ethernet 10
16-Mbps Token Ring 6
FDDI/Fast Ethernet 1
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136 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 10: Record the OSPF Cost of the Serial and Fast Ethernet
Interfaces
Using the show ip ospf interface command, record the OSPF cost of the serial and Fast Ethernet interfaces:
■ OSPF cost of serial interface: 64
■ OSPF cost of Ethernet interface: 1
Do these agree with the calculations? Yes
The clock rate set for the interface should have been 64,000. This is what has been used as a default to this
point and specified in Lab 1-2, “Review of Basic Router Configuring with RIP.” Therefore, to calculate the
cost of this bandwidth, you need to divide 10 8 by 64,000.
Task 11: Manually Set the Cost on the Serial Interface
On the serial interface of the Cairo router, set the OSPF cost to 1562 by typing ip ospf cost 1562 at the
serial interface configuration mode prompt.
Cairo(config)#interface serial 0/0
Cairo(config-if)#ip ospf cost 1562
Cairo(config-if)#end
Task 12: Verify Cost
Note that it is essential that all connected links agree about the cost for consistent calculation of the SPF in
an area.
Step 1. Verify that the interface OSPF cost was successfully modified.
Cairo#show ip ospf interface
Serial0/0 is up, line protocol is up
Internet Address 192.168.1.1/30, Area 0
Process ID 1, Router ID 192.168.1.129, Network Type POINT_TO_POINT
Cost: 1562
Transmit Delay is 1 sec, State POINT_TO_POINT,
Step 2. Reverse the effect of this command by entering the command no ip ospf cost in interface configuration
mode.
Step 3. Verify that the default cost for the interface has returned.
Serial0/0 is up, line protocol is up
Internet Address 192.168.1.1/30, Area 0
Process ID 1, Router ID 192.168.1.129, Network Type POINT_TO_POINT,
Cost: 64
Transmit Delay is 1 sec, State POINT_TO_POINT,
Step 4. Enter the command bandwidth 2000 at the serial 0 interface configuration mode prompt.
Record the new OSPF cost of the serial interface. 50
Can the OSPF cost of an Ethernet interface be modified in this way? Yes
You can set the speed on an Ethernet interface. Will this affect the OSPF cost of that interface?
Yes

Step 5. Verify or explain the previous answer.
You cannot change the speed on the Ethernet interfaces of 2500 series routers. You can change
the bandwidth used in calculations with the bandwidth command. On routers with Fast
Ethernet, you can change the speed on a Fast Ethernet interface with the speed command.
Once changed, OSPF will use the new speed as the bandwidth variable for the cost calculation.
FastEthernet0/0 is up, line protocol is up
Internet Address 192.168.1.129/25, Area 0
Process ID 1, Router ID 192.168.1.129, Network Type BROADCAST, Cost:
50
Transmit Delay is 1 sec, State DR, Priority 1
Step 6. Reset the bandwidth on the serial interface by using no bandwidth 2000 at the serial 0 interface
configuration mode prompt.
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.
Curriculum Lab 2-4: Configuring OSPF Authentication
(2.3.4)
Figure 2-13 Topology for Lab 2-4
Straight-Through Cable
Table 2-8 Lab Equipment Configuration: Part I
Area 0
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable
Chapter 2: Single-Area OSPF 137
Router Designation Router Name Routing Protocol Network Statements
Router 1 Dublin OSPF 192.168.1.0
Router 2 Washington OSPF 192.168.1.0
192.168.0.0

138 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 2-9 Lab Equipment Configuration: Part II
Router IP Host Fast Ethernet 0 Inter-face Serial 0 Address/ Loopback 0
Designation Table Entry Address/Subnet Type Serial 0 Subnet Mask Address/
Mask Subnet Mask
Router 1 Washington 192.168.1.129/26 DCE 192.168.1.1/30 192.168.31.11/32
Router 2 Dublin 192.168.0.1/24 DTE 192.168.1.2/30 192.168.31.22/32
The interface type and address/subnet mask for the serial 1 interface on both routers is not applicable for
this lab.
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Set up an IP addressing scheme for the OSPF area.
■ Configure and verify OSPF routing.
■ Introduce OSPF authentication into the area.
Background/Preparation
Cable a network that is similar to the one in Figure 2-13. You can use any router that meets the interface
requirements in Figure 2-13 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname, console, virtual terminal, and
enable passwords. Next, configure the interfaces and IP hostnames according to the Lab Equipment
Configuration tables, Tables 2-8 and 2-9. If you have problems configuring the router basics, refer to Lab
1-2, “Review of Basic Router Configuring with RIP.”
Note: You may need to add the command ip subnet-zero because of the use of the ZERO subnet with VLSM on the
192.168.1.0/30 and 192.168.1.128/26 networks.
Note: Do not configure the routing protocol until you are specifically told to.
Dublin
Router>enable
Router#configure terminal
Router(config)#hostname Dublin
Dublin(config)#enable secret class
Dublin(config)#line console 0

Dublin(config-line)#password cisco
Dublin(config-line)#login
Dublin(config-line)#line vty 0 4
Dublin(config-line)#password cisco
Dublin(config-line)#login
Dublin(config-line)#exit
Dublin(config)#interface loopback 0
Dublin(config-if)#ip address 192.168.31.11 255.255.255.255
Dublin(config-if)#interface serial 0
Dublin(config-if)#ip address 192.168.1.1 255.255.255.252
Dublin(config-if)#clockrate 64000
Dublin(config-if)#no shutdown
Dublin(config-if)#interface fastethernet 0/0
Dublin(config-if)#ip address 192.168.1.129 255.255.255.192
Dublin(config-if)#no shutdown
Dublin(config-if)#exit
Dublin(config)#ip host Washington 192.168.0.1 192.168.1.2
Dublin(config)#exit
Washington
Router>enable
Router#configure terminal
Router(config)#hostname Washington
Washington(config)#enable secret class
Washington(config)#line console 0
Washington(config-line)#password cisco
Washington(config-line)#login
Washington(config-line)#line vty 0 4
Washington(config-line)#password cisco
Washington(config-line)#login
Washington(config-line)#exit
Washington(config)#interface loopback 0
Washington(config-if)#ip address 192.168.31.22 255.255.255.255
Washington(config-if)#interface serial 0
Washington(config-if)#ip address 192.168.1.2 255.255.255.252
Washington(config-if)#no shutdown
Washington(config-if)#interface fastethernet 0/0
Washington(config-if)#ip address 192.168.0.1 255.255.255.0
Washington(config-if)#no shutdown
Washington(config-if)#exit
Washington(config)#ip host Dublin 192.168.1.129 192.168.1.1
Washington(config)#exit
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140 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
Dublin#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Washington#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Why should you save the running configuration to the startup configuration?
Saving the configuration will allow the router to keep the configuration after a reload or power down.
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Dublin
IP address: 192.168.1.130
Subnet mask: 255.255.255.192
Default gateway: 192.168.1.129
Host connected to router Washington
IP address: 192.168.0.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.0.1
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000,
check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process required to get communication working by using OSPF as the
routing protocol.
Task 4: Verify Connectivity
Ping from one of the connected router serial interfaces to the other.
Was the ping successful? Yes
If the ping was not successful, troubleshoot the router’s configurations until the ping is successful.
Task 5: Configure OSPF Routing on Both Routers
Step 1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks
are in area 0. Refer to Lab 2-2, “Configuring OSPF with Loopback Addresses,” for a
review on configuring OSPF routing.
Dublin(config)#router ospf 1
Dublin(config-router)#network 192.168.1.128 0.0.0.127 area 0
Dublin(config-router)#network 192.168.1.0 0.0.0.3 area 0
Dublin(config-router)#end

Washington(config)#router ospf 1
Washington(config-router)#network 192.168.0.0 0.0.0.255 area 0
Washington(config-router)#network 192.168.1.0 0.0.0.3 area 0
Washington(config-router)#end
Step 2. Examine the Dublin router running the configuration file. Did the IOS version automatically
add lines under router OSPF 1? Yes
Step 3. Show the routing table for the Dublin router.
Dublin#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS
inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.31.11 is directly connected, Loopback0
O 192.168.0.0/24 [110/51] via 192.168.1.2, 00:14:23, Serial0/0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/30 is directly connected, Serial0/0
C 192.168.1.128/26 is directly connected, FastEthernet0/0
Do entries exist in the routing table? Yes
Why?
Because a routing protocol has been configured and routing updates are being made.
Task 6: Test Network Connectivity
Ping the Dublin host from the Washington host. Was it successful? Yes
If not, troubleshoot as necessary.
Task 7: Set Up OSPF Authentication
OSPF authentication is being established on the routers in the network. First, introduce authentication only
on the Dublin router.
In interface configuration mode on serial 0, enter the command ip ospf message-digest-key 1 md5 7
asecret.
Dublin(config)#interface Serial 0
Dublin(config-if)#ip ospf message-digest-key 1 md5 ?
Encryption type (0 for not yet encrypted, 7 for proprietary)
Dublin(config-if)#ip ospf message-digest-key 1 md5 7 ?
LINE The OSPF password (key)
Dublin(config-if)#ip ospf message-digest-key 1 md5 7 asecret
What is the OSPF password that is being used for MD5 authentication? asecret
What encryption type is being used? Type 7
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142 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Enable OSPF Authentication in this Area, Area 0
Dublin(config-if)#router ospf 1
Dublin(config-router)#area 0 authentication
Step 1. Wait for a few seconds. Does the router generate output? Yes
Step 2. Enter the command show ip ospf neighbor.
Are there OSPF neighbors? No
Step 3. Examine the routing table by entering show ip route.
Are there OSPF routes in the Dublin router routing table? No
Can the Dublin host ping the Washington host? No
Step 4. Enter configuration commands, one per line. End with Ctrl-Z.
Washington#configure terminal
Washington(config)#interface serial 0
Washington(config-if)#ip ospf message-digest-key 1 md5 7 asecret
Washington(config-if)#router ospf 1
Washington(config-router)#area 0 authentication
Step 5. Verify that there is an OSPF neighbor by entering the show ip ospf neighbor command.
Neighbor ID Pri State Dead Time Address Interface
192.168.1.129 1 FULL/ - 00:00:38 192.168.1.1 Serial0
Step 6. Show the routing table by typing show ip route.
Washington#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS
inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.31.22 is directly connected, Loopback0
C 192.168.0.0/24 is directly connected, FastEthernet0/0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/30 is directly connected, Serial0/0
O 192.168.1.128/26 [110/791] via 192.168.1.1, 00:18:41, Serial0/0
Step 7. Ping the Washington host from Dublin. If it is not successful, troubleshoot as necessary.
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.

Curriculum Lab 2-5: Configuring OSPF Timers (2.3.5)
Figure 2-14 Topology for Lab 2-5
Straight-Through Cable
Table 2-10 Lab Equipment Configuration: Part I
Router Designation Router Name Routing Protocol Network Statements
Router 1 Sydney OSPF 192.168.1.0
Router 2 Rome OSPF 192.168.1.0
192.168.0.0
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 2-11 Lab Equipment Configuration: Part II
Area 0
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable
Chapter 2: Single-Area OSPF 143
Router IP Host Fast Ethernet 0 Inter-face Serial 0 Address/ Loopback 0
Designation Table Entry Address/Subnet Type Serial 0 Subnet Mask Address/
Mask Subnet Mask
Router 1 Rome 192.168.1.129/26 DCE 192.168.1.1/30 192.168.31.11/32
Router 2 Sydney 192.168.0.1/24 DTE 192.168.1.2/30 192.168.31.22/32
The interface type and address/subnet mask for the serial 1 interface on both routers is not applicable for
this lab.
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.

144 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Objectives
■ Set up an IP addressing scheme for the OSPF area.
■ Configure and verify OSPF routing.
■ Modify OSPF interface timers to adjust efficiency of the network.
Background/Preparation
Cable a network that is similar to the one in Figure 2-14. You can use any router that meets the interface
requirements in Figure 2-14 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise. Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname, console, virtual terminal, and
enable passwords. Next, configure the interfaces and IP hostnames according to the Lab Equipment
Configuration tables, Tables 2-10 and 2-11. If you have problems configuring the router basics, refer to
Lab 1-2, “Review of Basic Router Configuring with RIP.”
Note: You may need to add the command ip subnet-zero because of the use of the ZERO subnet with VLSM on the
192.168.1.0/30 and 192.168.1.128/26 networks.
Note: Do not configure the routing protocol until you are specifically told to.
Sydney
Router>enable
Router#configure terminal
Router(config)#hostname Sydney
Sydney(config)#enable secret class
Sydney(config)#line console 0
Sydney(config-line)#password cisco
Sydney(config-line)#login
Sydney(config-line)#line vty 0 4
Sydney(config-line)#password cisco
Sydney(config-line)#login
Sydney(config-line)#exit
Sydney(config)#interface loopback 0
Sydney(config-if)#ip address 192.168.31.11 255.255.255.255
Sydney(config-if)#interface serial 0
Sydney(config-if)#ip address 192.168.1.1 255.255.255.252
Sydney(config-if)#clockrate 64000
Sydney(config-if)#no shutdown
Sydney(config-if)#interface FastEthernet 0
Sydney(config-if)#ip address 192.168.1.129 255.255.255.192
Sydney(config-if)#no shutdown
Sydney(config-if)#exit

Sydney(config)#ip host Rome 192.168.0.1 192.168.1.2
Sydney(config)#exit
Rome Router>enable
Router#configure terminal
Router(config)#hostname Rome
Rome(config)#enable secret class
Rome(config)#line console 0
Rome(config-line)#password cisco
Rome(config-line)#login
Rome(config-line)#line vty 0 4
Rome(config-line)#password cisco
Rome(config-line)#login
Rome(config-line)#exit
Rome(config)#interface loopback 0
Rome(config-if)#ip address 192.168.31.22 255.255.255.255
Rome(config-if)#interface serial 0
Rome(config-if)#ip address 192.168.1.2 255.255.255.252
Rome(config-if)#no shutdown
Rome(config-if)#interface FastEthernet 0
Rome(config-if)#ip address 192.168.0.1 255.255.255.0
Rome(config-if)#no shutdown
Rome(config-if)#exit
Rome(config)#ip host Sydney 192.168.1.129 192.168.1.1
Rome(config)#exit
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
Sydney#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Rome#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Why should you save the running configuration to the startup configuration?
Saving the configuration will allow the router to keep the configuration after a reload or power down.
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Sydney
IP address: 192.168.1.130
Subnet mask: 255.255.255.192
Default gateway: 192.168.1.129
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146 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Host connected to router Rome
IP address: 192.168.0.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.0.1
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000,
check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process that is required to get communication working by using OSPF as
the routing protocol.
Task 4: Verify Connectivity
Ping from one of the connected serial interfaces to the other.
Was the ping successful? Yes
If the ping was not successful, troubleshoot the router configurations until the ping is successful.
Task 5: Configure OSPF Routing on both Routers
Step 1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks
are in area 0. Refer to Lab 2-2, “Configuring OSPF with Loopback Interfaces,” for a
review on configuring OSPF routing.
Sydney(config)#router ospf 1
Sydney(config-router)#network 192.168.1.128 0.0.0.127 area 0
Sydney(config-router)#network 192.168.1.0 0.0.0.3 area 0
Sydney(config-router)#end
Rome(config)#router ospf 1
Rome(config-router)#network 192.168.0.0 0.0.0.255 area 0
Rome(config-router)#network 192.168.1.0 0.0.0.3 area 0
Rome(config-router)#end
Did the IOS version automatically add lines under router OSPF 1? Yes
Step 2. Show the routing table for the Sydney router.
Sydney#show ip route
Do entries exist in the routing table? Yes
Task 6: Test Network Connectivity
Ping the Sydney host from the Rome host. Was it successful? Yes
If not, troubleshoot as necessary.

Task 7: Observe OSPF Traffic
Step 1. At privileged EXEC mode, type the command debug ip ospf events and observe the output.
How frequently are Hello messages sent? Every 10 seconds
Where are Hello messages coming from?
Hello messages are coming from 192.168.31.22 area 0 on the local Serial0 interface with the
address 192.168.1.2
Step 2. Turn off debugging by typing no debug ip ospf events or undebug all.
Task 8: Show Interface Timer Information
Show the hello and dead interval timers on the Sydney router Ethernet and serial interfaces by entering the
command show ip ospf interface in privileged EXEC mode.
Record the Hello and Dead interval timers for these interfaces:
■ Hello interval: 10
■ Dead interval: 40
What is the purpose of the dead interval?
It specifies the amount of time wait while Hellos are not being received before flagging the router as being
down.
Task 9: Modify the OSPF Timers
Step 1. Modify the Hello and Dead interval timers to smaller values to try to improve performance. On
the Sydney router only, enter the commands ip ospf hello-interval 5 and ip ospf dead-interval
20 for interface serial 0.
Sydney(config)#interface Serial 0
Sydney(config-if)#ip ospf hello-interval 5
Sydney(config-if)#ip ospf dead-interval 20
Step 2. Wait for a minute and then enter the command show ip ospf neighbor.
Do OSPF neighbors exist? No
Task 10: Examine the Routing Table
Examine the Sydney router routing table by entering show ip route.
Do OSPF routes exist in the table? No
Can the Sydney host ping the Rome host? No
Task 11: Look at the OSPF Data Transmissions
Enter the command debug ip ospf events in privileged EXEC mode.
Is there an issue that is identified? Yes
If there is, what is the issue?
Hello and Dead intervals are mismatched.
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148 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 12: Check the Rome Router Routing Table Status
On the Rome router, check the routing table by typing show ip route.
Do OSPF routes exist in the table? No
Task 13: Set the Rome Router Interval Timers
Step 1. Match the timer values on the Rome serial link with the Sydney router.
Rome(config)#interface serial 0
Rome(config-if)#ip ospf hello-interval 5
Rome(config-if)#ip ospf dead-interval 20
Step 2. Verify the OSPF neighbor by entering the show ip ospf neighbor command.
Neighbor ID Pri State Dead Time Address Interface
192.168.31.11 1 FULL/ - 00:00:17 192.168.1.1 Serial0
Step 3. Show the routing table by typing show ip route.
Rome#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS
inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
192.168.31.0/32 is subnetted, 1 subnets
C 192.168.31.22 is directly connected, Loopback0
C 192.168.0.0/24 is directly connected, Ethernet0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/30 is directly connected, Serial0
O 192.168.1.128/25 [110/782] via 192.168.1.1, 00:00:12, Serial0
Do OSPF routes exist in the table? Yes
Step 4. Ping the Rome host from Sydney. If this is not successful, troubleshoot the configurations.
Task 14: Reset the Router’s Interval Timers to the Default Values
Use the no form of the ip ospf hello-interval and the ip ospf dead-interval to reset the OSPF timers back
to their default values.
Task 15: Verify that the Interval Timers Are Returned to the
Default Values
Use the show ip ospf interface command to verify that the timers are reset to their default values.
Are the values back to the default? Yes
If not, repeat Task 14 and verify again.

After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.
Curriculum Lab 2-6: Propagating Default Routes in an
OSPF Domain (2.3.6)
Figure 2-15 Topology for Lab 2-6
Router 2
Straight-Through Cable
Rollover (Console) Cable
Table 2-12 Lab Equipment Configuration: Part I
Router Router Routing Network Statements Loopback 0 Address/
Designation Name Protocol Subnet Mask
Router 1 Tokyo OSPF 192.168.1.0 192.168.31.11/32
Router 2 Madrid OSPF 192.168.1.0 192.168.0.0 192.168.31.22/32
The enable secret password for all routers is class.
The enable, VTY, and console passwords for each router is cisco.
DTE
DTE
DCE DCE
Router 3 Router 1
Area 0
Crossover Cable
Serial Cable
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150 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 2-13 Lab Equipment Configuration: Part II
Router IP Host Fast Ethernet 0 Interface Serial 0 Address/ Inter-face Serial 1
Designation Table Entry Address/Subnet Type Subnet Mask Type Serial 1 Address/
Mask Serial 0 Subnet Mask
Router 1 Madrid 192.168.1.129/26 DCE 192.168.1.1/30 N/A N/A
Router 2 Tokyo 192.168.0.1/24 DTE 192.168.1.2/30 DTE 200.20.20.2/30
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Set up an IP addressing scheme for the OSPF area.
■ Configure and verify OSPF routing.
■ Configure the OSPF network so that all hosts in an OSPF area can connect to outside networks.
Background/Preparation
Cable a network that is similar to the one in Figure 2-15. You can use any router that meets the interface
requirements in Figure 2-15 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise. Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the ISP Router
Normally, the ISP would configure the ISP router (Router 3). For the purpose of this lab, after you erase
the old configuration, configure the ISP router (Router 3) by typing the following:
Router>enable
Router#configure terminal
Router(config)#hostname ISP
ISP(config)#line vty 0 4
ISP(config-line)#password cisco
ISP(config-line)#login
ISP(config-line)#interface serial 1
ISP(config-if)#ip address 200.20.20.1 255.255.255.252
ISP(config-if)#clock rate 64000
ISP(config-if)#no shutdown
ISP(config-if)#interface loopback 0
ISP(config-if)#ip address 138.25.6.33 255.255.255.255
ISP(config-if)#exit
ISP(config)#ip route 192.168.1.0 255.255.255.0 200.20.20.2
ISP(config)#ip route 192.168.0.0 255.255.255.0 200.20.20.2
ISP(config)#end
ISP#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Building configuration...
[OK]
ISP#

Task 2: Configure the Area 0 OSPF Routers
On the routers, enter global configuration mode and configure the hostname, console, virtual terminal, and
enable passwords. Next, configure the interfaces and IP hostnames according to the Lab Equipment
Configuration tables, Tables 2-12 and 2-13. If you have problems configuring the router basics, refer to
Lab 1-2, “Review of Basic Router Configuring with RIP.”
Note: Do not configure the routing protocol until you are specifically told to.
Tokyo
Router>enable
Router#configure terminal
Router(config)#hostname Tokyo
Tokyo(config)#enable secret class
Tokyo(config)#line console 0
Tokyo(config-line)#password cisco
Tokyo(config-line)#login
Tokyo(config-line)#line vty 0 4
Tokyo(config-line)#password cisco
Tokyo(config-line)#login
Tokyo(config-line)#exit
Tokyo(config)#interface loopback 0
Tokyo(config-if)#ip address 192.168.31.11 255.255.255.255
Tokyo(config-if)#interface serial 0
Tokyo(config-if)#ip address 192.168.1.1 255.255.255.252
Tokyo(config-if)#clockrate 64000
Tokyo(config-if)#no shutdown
Tokyo(config-if)#interface fastethernet 0
Tokyo(config-if)#ip address 192.168.1.129 255.255.255.192
Tokyo(config-if)#no shutdown
Tokyo(config-if)#exit
Tokyo(config)#ip host Madrid 192.168.0.1 192.168.1.2
Tokyo(config)#exit
Madrid
Router>enable
Router#configure terminal
Router(config)#hostname Madrid
Madrid(config)#enable secret class
Madrid(config)#line console 0
Madrid(config-line)#password cisco
Madrid(config-line)#login
Madrid(config-line)#line vty 0 4
Madrid(config-line)#password cisco
Madrid(config-line)#login
Madrid(config-line)#exit
Madrid(config)#interface loopback 0
Madrid(config-if)#ip address 192.168.31.22 255.255.255.255
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152 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Madrid(config-if)#interface serial 0
Madrid(config-if)#ip address 192.168.1.2 255.255.255.252
Madrid(config-if)#no shutdown
Madrid(config-if)#interface serial 1
Madrid(config-if)#ip address 200.20.20.2 255.255.255.252
Madrid(config-if)#no shutdown
Madrid(config-if)#interface fastethernet 0
Madrid(config-if)#ip address 192.168.0.1 255.255.255.0
Madrid(config-if)#no shutdown
Madrid(config-if)#exit
Madrid(config)#ip host Tokyo 192.168.1.129 192.168.1.1
Madrid(config)#exit
Task 3: Save the Configuration Information from Privileged EXEC
Command Mode
Tokyo#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Madrid#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Why should you save the running configuration to the startup configuration?
Saving the configuration will allow the router to keep the configuration after a reload or power down.
Task 4: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Sydney
IP address: 192.168.1.130
Subnet mask: 255.255.255.192
Default gateway: 192.168.1.129
Host connected to router Rome
IP address: 192.168.0.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.0.1
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000,
check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process that is required to get communication working by using OSPF as
the routing protocol.

Task 5: Verify Connectivity
Ping from the Madrid router to both the Tokyo and ISP routers.
Madrid#ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Madrid#ping 200.20.20.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 200.20.20.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
Were the pings successful? Yes
If the ping was not successful, troubleshoot the router configurations until the ping is successful.
Task 6: Configure OSPF Routing on Both Area 0 Routers
Step 1. Configure OSPF routing on each router. Use OSPF process number 1 and ensure that all networks
are in area 0. Refer to Lab 2-2, “Configuring OSPF with Loopback Addresses,” for a
review on configuring OSPF routing.
Tokyo(config)#router ospf 1
Tokyo(config-router)#network 192.168.1.128 0.0.0.127 area 0
Tokyo(config-router)#network 192.168.1.0 0.0.0.3 area 0
Tokyo(config-router)#end
Madrid(config)#router ospf 1
Madrid(config-router)#network 192.168.0.0 0.0.0.255 area 0
Madrid(config-router)#network 192.168.1.0 0.0.0.3 area 0
Madrid(config-router)#end
Did the IOS version automatically add lines under router OSPF 1? Yes
Step 2. Show the routing table for the Tokyo router.
Tokyo#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS
inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
192.168.31.0/32 is subnetted, 1 subnets
C 192.168.31.11 is directly connected, Loopback0
O 192.168.0.0/24 [110/65] via 192.168.1.2, 00:00:14, Serial0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/30 is directly connected, Serial0
C 192.168.1.128/24 is directly connected, FastEthernet0
Do entries exist in the routing table? Yes
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154 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 7: Test Network Connectivity
Ping the Tokyo host from the Madrid host. Was it successful? Yes
If not, troubleshoot as necessary.
Task 8: Observe OSPF Traffic
Step 1. At privileged EXEC mode, type the command debug ip ospf events and observe the output.
Is there OSPF traffic? Yes
Step 2. Turn off debugging by typing no debug ip ospf events or undebug all.
Task 9: Create a Default Route to the ISP
On the Madrid router only, type a static default route via the serial 1 interface.
Madrid(config)#ip route 0.0.0.0 0.0.0.0 200.200.200.1
Task 10: Verify the Default Static Route
Verify the default static route by looking at the Madrid routing table.
Madrid#show ip route
01:12:26: %SYS-5-CONFIG_I: Configured from console by consolehow ip
route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS
inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 200.20.20.1 to network 0.0.0.0
200.20.20.0/30 is subnetted, 1 subnets
C 200.20.20.0 is directly connected, Serial1
192.168.31.0/32 is subnetted, 1 subnets
C 192.168.31.22 is directly connected, Loopback0
C 192.168.0.0/24 is directly connected, FastEthernet0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.0/30 is directly connected, Serial0
O 192.168.1.128/24 [110/782] via 192.168.1.1, 00:01:44, Serial0
S* 0.0.0.0/0 [1/0] via 200.20.20.1
Is the default route in the routing table? Yes

Task 11: Verify Connectivity from the Madrid Router
Step 1. Verify connectivity from the Madrid router by pinging the ISP serial 1 interface from the
Madrid router.
Can the interface be pinged? Yes
Step 2. Ping from a DOS window on the host that is attached to the Madrid router Fast Ethernet interface
to the ISP router serial 1 interface.
Can the interface be pinged? Yes
Step 3. Ping again from the host to the loopback address on the ISP router, which represents the ISP
connection to the Internet.
Can the loopback interface be pinged? Yes
Step 4. All these pings should be successful. If they are not, troubleshoot the configurations on the host
and the Madrid and ISP routers.
Task 12: Verify Connectivity from the Tokyo Router
Verify connectivity from the Tokyo router by pinging the ISP router serial 1 interface from the Tokyo
router.
Can the interface be pinged? No
If yes, why? If not, why not?
There is no route to the ISP router.
Task 13: Redistribute the Static Default Route
Propagate the gateway of last resort to the other routers in the OSPF domain. At the configure router
prompt on the Madrid router, type default-information originate.
Madrid(config-router)#default-information originate
Does a default route now exist on the Tokyo router? Yes
What is the address of the gateway of last resort? 192.168.1.2
There is an O*E2 entry in the routing table. What type of route is it?
OSPF external route type 2
Can the ISP server address at 138.25.16.33 be pinged from both workstations? Yes
If not, troubleshoot both hosts and all three routers.
Chapter 2: Single-Area OSPF 155
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.

156 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Comprehensive Lab 2-7: OSPF Configuration
Figure 2-16 OSPF Configuration
Table 2-14 Lab 2-7 Addressing Scheme
Device Interface IP Address Subnet Mask
RTA Fa0/0 192.168.1.1 255.255.255.192
S0/1 192.168.1.245 255.255.255.252
S0/0 192.168.1.254 255.255.255.252
Lo0 209.165.202.129 255.255.255.255
RTB S0/1 192.168.1.246 255.255.255.192
Fa0/0 192.168.1.65 255.255.255.192
S0/0 192.168.1.249 255.255.255.252
RTC S0/1 192.168.1.250 255.255.255.252
Objectives
192.168.1.128/26
■ Configure OSPF routing
■ Modify OSPF cost
Fa0/0 192.168.1.129 255.255.255.192
S0/0 192.168.1.253 255.255.255.252
■ Configure MD5 authentication
■ Adjust OSPF timers
Address Space
192.168.1.0/24
Fa0/0
■ Configure and propagate a default route
S0/0
192.168.1.0/26
Fa0/0
RTA
S0/1
DCE
192.168.1.252/30 192.168.1.244/30
OSPF
Area 0
T1 T1
S0/0
DCE
S0/1
RTC
S0/1
386 kps
192.168.1.248/30 S0/0
DCE
RTB
Simulated ISP Link
Lo0 209.165.202.129/32
192.168.1.64/26
Fa0/0

Equipment
The topology shown in Figure 2-16 is using 2600 series routers. This lab can be done with any combination
of 1700, 2500, and 2600 series routers. Connectivity to an ISP is simulated with a loopback interface
on RTA.
NetLab Compatibility Notes
This lab is fully compatible with a standard NetLab three router pod.
Task 1: Cable the Topology and Basic Configurations
Step 1. Cable the topology as shown. If DCE/DTE connections and interfaces are different from those
shown in Figure 2-16 and the table, relabel the figure to match your connections.
Step 2. Configure the routers with basic router configurations, including
■ Hostnames and host tables
■ Enable secret password and MOTD banner
■ Line configurations
■ IOS-specific commands (e.g. ip subnet-zero with IOS versions prior to 12)
Step 3. The following is a basic configuration for RTA:
Router(config)#hostname RTA
RTA(config)#ip subnet-zero
RTA(config)#no ip domain-lookup
RTA(config)#ip host RTC 192.168.1.253 192.168.1.254
RTA(config)#ip host RTB 192.168.1.246 192.168.1.249
RTA(config)#banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
RTA(config)#line con 0
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#line aux 0
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#line vty 0 4
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#end
RTA#copy run start
Chapter 2: Single-Area OSPF 157

158 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 2: Configure Interfaces and OSPF Routing
Step 1. Use Table 2-14 and the topology shown in Figure 2-16 to configure each router with the correct
interface addresses. To simulate an ISP connection, use the following configuration on RTA:
RTA(config)#interface Loopback0
RTA(config-if)#description Simulated Link to ISP
RTA(config-if)#ip address 209.165.202.129 255.255.255.255
Step 2. Configure OSPF routing on RTA, RTB, and RTC. Do not configure the simulated ISP loopback
interface as part of OSPF. The configuration for RTA is as follows:
RTA(config)#router ospf 1
RTA(config-router)#network 192.168.1.0 0.0.0.63 area 0
RTA(config-router)#network 192.168.1.244 0.0.0.3 area 0
RTA(config-router)#network 192.168.1.252 0.0.0.3 area 0
Task 3: Verify Connectivity
Step 1. You should now have full connectivity between RTA, RTB, and RTC. Issue the show ip route
command to verify full convergence.
Routing table on RTA:
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
O 192.168.1.64/26 [110/65] via 192.168.1.246, 00:00:48, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
O 192.168.1.248/30 [110/128] via 192.168.1.246, 00:00:48, Serial0/1
[110/128] via 192.168.1.253, 00:00:48, Serial0/0
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
O 192.168.1.128/26 [110/65] via 192.168.1.253, 00:00:49, Serial0/0
Step 2. Notice that RTA has four connected routes (including the simulated ISP link) and three OSPF
routes. RTB and RTC should both have three connected routes and three OSPF routes.
Step 3. Pings sourced from any router to a LAN interface on another router should succeed.
RTA#ping 192.168.1.65
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.65, timeout is 2 seconds:
!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/32 ms
RTA#ping 192.168.1.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/29/32 ms
Task 4: Modify OSPF Cost
Step 1. At this point, all routers are using the default bandwidth for serial interfaces: for 2500s and
2600s, 1544 kbps; for 1700s, 128 kbps. Use the show interface serial command to view the
bandwidth used to calculate cost.
RTB#show interface s0/0
Serial0/0 is up, line protocol is up
Hardware is PowerQUICC Serial
Description: Link to RTC
Internet address is 192.168.1.249/30
MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
(output omitted)
Step 2. When RTB pings the LAN interface on RTC, it sends it directly to RTC even though the path
through RTA is faster.
RTB#traceroute 192.168.1.129
Type escape sequence to abort.
Tracing the route to 192.168.1.129
1 RTC (192.168.1.250) 16 msec * 12 msec
RTB#
Step 3. Configure both RTB and RTC with the correct bandwidth.
RTB(config)#interface s0/0
RTB(config-if)#bandwidth 386
!
RTC(config)#interface s0/1
RTC(config-if)#bandwidth 386
Step 4. Verify that RTB sends pings destined for the LAN on RTC to RTA, which then routes the ping
to RTC.
RTB#traceroute 192.168.1.129
Type escape sequence to abort.
Tracing the route to 192.168.1.129
1 RTA (192.168.1.245) 16 msec 12 msec 16 msec
2 RTC (192.168.1.253) 28 msec * 16 msec
RTB#
Chapter 2: Single-Area OSPF 159

160 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 5: Configure MD5 Authentication
Step 1. To make sure routing updates come from trusted sources, configure each router to use MD5
authentication. The configuration for RTA follows:
RTA(config)#interface serial 0/0
RTA(config-if)#ip ospf message-digest-key 1 md5 7 allrouters
RTA(config)#interface serial 0/1
RTA(config-if)#ip ospf message-digest-key 1 md5 7 allrouters
RTA(config-if)#router ospf 1
RTA(config-router)#area 0 authentication message-digest
Step 2. After configuring authentication on each router, neighbor adjacency will go to the DOWN state
and then reinitialize. Make sure that all routing tables have reconverged by issuing the show ip
route command. The table for RTA follows:
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
O 192.168.1.64/26 [110/65] via 192.168.1.246, 00:06:25, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
O 192.168.1.248/30 [110/323] via 192.168.1.246, 00:06:25, Serial0/1
[110/323] via 192.168.1.253, 00:06:25, Serial0/0
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
O 192.168.1.128/26 [110/65] via 192.168.1.253, 00:06:26, Serial0/0
Step 3. You can verify authentication by using the show ip ospf command or the show ip ospf interface
command.
RTA#show ip ospf
Routing Process “ospf 1” with ID 209.165.202.129
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 0. Checksum Sum 0x0
Number of opaque AS LSA 0. Checksum Sum 0x0
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)

Number of interfaces in this area is 3
Area has message digest authentication
SPF algorithm executed 2 times
Area ranges are
Number of LSA 3. Checksum Sum 0x1F45E
Number of opaque link LSA 0. Checksum Sum 0x0
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
RTA#show ip ospf interface s0/0
Serial0/0 is up, line protocol is up
Internet Address 192.168.1.254/30, Area 0
Process ID 1, Router ID 209.165.202.129, Network Type POINT_TO_POINT, Cost:
64
Transmit Delay is 1 sec, State POINT_TO_POINT,
Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5
Hello due in 00:00:01
Index 3/3, flood queue length 0
Next 0x0(0)/0x0(0)
Last flood scan length is 1, maximum is 1
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 1, Adjacent neighbor count is 1
Adjacent with neighbor 10.0.0.1
Suppress hello for 0 neighbor(s)
Message digest authentication enabled
Youngest key id is 1
Task 6: Adjust OSPF Timers
Step 1. Notice in the previous output for show ip ospf interface that the Hello and dead interval timers
are shown as 10 and 40, respectively. Configure these intervals to be 40 and 160 on all three
routers.
RTA(config)#interface s0/0
RTA(config-if)#ip ospf hello-interval 40
RTA(config-if)#ip ospf dead-interval 160
RTA(config)#interface s0/1
RTA(config-if)#ip ospf hello-interval 40
RTA(config-if)#ip ospf dead-interval 160
Chapter 2: Single-Area OSPF 161
Step 2. Verify that all routers have full routing tables and have re-established neighbor adjacencies. If
adjacency has not been re-established, you can use the debug ip ospf events command to find
where there might be a timing mismatch.
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR

162 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
P - periodic downloaded static route
Gateway of last resort is not set
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
O 192.168.1.64/26 [110/65] via 192.168.1.246, 00:00:04, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
O 192.168.1.248/30 [110/323] via 192.168.1.246, 00:00:04, Serial0/1
[110/323] via 192.168.1.253, 00:00:04, Serial0/0
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
O 192.168.1.128/26 [110/65] via 192.168.1.253, 00:00:05, Serial0/0
RTA#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
192.168.1.253 1 FULL/ - 00:02:19 192.168.1.253 Serial0/0
192.168.1.249 1 FULL/ - 00:02:16 192.168.1.246 Serial0/1
Task 7: Configure and Propagate a Default Route
Step 1. Because the ISP is only simulated, RTA does not have a real default route. However, you can
simulate a default route by configuring it to forward to a null interface.
RTA(config)#ip route 0.0.0.0 0.0.0.0 null 0
Step 2. Now, you can configure RTA to propagate the default route to RTB and RTC.
RTA(config)#router ospf 1
RTA(config-router)#default-information originate
Step 3. RTB and RTC should now be able to successfully ping the 209.165.202.129 interface, which
verifies that both routers have a working default route.
RTA hostname RTA
!
RTB#ping 209.165.202.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/28/28 ms
RTC#ping 209.165.202.129
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/33/48 ms
enable secret class
!
ip subnet-zero

no ip domain-lookup
ip host RTB 192.168.1.246 192.168.1.249
ip host RTC 192.168.1.253 192.168.1.250
!
!
interface Loopback0
!
description Simulated Link to ISP
ip address 209.165.202.129 255.255.255.255
interface FastEthernet0/0
!
description RTA LAN
ip address 192.168.1.1 255.255.255.192
interface Serial0/0
!
description Link to RTC
ip address 192.168.1.254 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
clockrate 64000
no shutdown
interface Serial0/1
!
description Link to RTB
ip address 192.168.1.245 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
clockrate 64000
no shutdown
router ospf 1
!
log-adjacency-changes
area 0 authentication message-digest
network 192.168.1.0 0.0.0.63 area 0
network 192.168.1.244 0.0.0.3 area 0
network 192.168.1.252 0.0.0.3 area 0
default-information originate
ip classless
ip route 0.0.0.0 0.0.0.0 Null0
no ip http server
!
!
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
Chapter 2: Single-Area OSPF 163

164 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
RTB hostname RTB
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host RTC 192.168.1.250 192.168.1.253
ip host RTA 192.168.1.245 192.168.1.254
!
interface FastEthernet0/0
!
description RTB LAN
ip address 192.168.1.65 255.255.255.192
no shutdown
interface Serial0/0
!
description Link to RTC
bandwidth 386
ip address 192.168.1.249 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
clockrate 64000
no shutdown
!Adjust clock rate for the correct interface, if needed

!
interface Serial0/1
!
description Link to RTA
ip address 192.168.1.246 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
no shutdown
router ospf 2
!
log-adjacency-changes
area 0 authentication message-digest
network 192.168.1.64 0.0.0.63 area 0
network 192.168.1.244 0.0.0.3 area 0
network 192.168.1.248 0.0.0.3 area 0
ip classless
no ip http server
!
!
snmp-server manager
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
Chapter 2: Single-Area OSPF 165

166 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
RTC
hostname RTC
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
!
!
interface FastEthernet0/0
!
description RTC LAN
ip address 192.168.1.129 255.255.255.192
no shutdown
interface Serial0/0
!
description Link to RTA
ip address 192.168.1.253 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
no shutdown
interface Serial0/1
!
description Link to RTB
bandwidth 386
ip address 192.168.1.250 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 40
no shutdown
router ospf 3
!
log-adjacency-changes
area 0 authentication message-digest
network 192.168.1.128 0.0.0.63 area 0
network 192.168.1.248 0.0.0.3 area 0
network 192.168.1.252 0.0.0.3 area 0
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0

exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
Challenge Lab 2-8: OSPF Design and Configuration
Figure 2-17 OSPF Design and Configuration
Public Web Server
209.165.202.129/32
Address Space
172.16.0.0/16
Lo0
209.165.201.0/30
ISP
S0/0
DCE
S0/0
Production LAN Lo0
Warehouse LAN Lo1
Marketing LAN Lo2
Management LAN Lo3
Purchasing LAN Lo4
HQ
S0/1
DCE
1
4
T1
East Region Lo0
North Region Lo1
South Region Lo2
West Region Lo3
International Lo4
WAN
S0/1
Chapter 2: Single-Area OSPF 167
172.16.0.0 / 18
172.16.64.0 / 19
172.16.96.0 / 20
172.16.112.0 / 21
172.16.120.0 / 22
172.16.255.252 / 30
Remote
172.16.128.0 / 20
172.16.144.0 / 20
172.16.160.0 / 20
172.16.176.0 / 20
172.16.192.0 / 20

168 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 2-15 Lab 2-8 Addressing Scheme
Device Interface IP Address Subnet Mask
ISP Lo0 209.165.202.129 255.255.255.255
S0/0 209.165.201.1 255.255.255.252
HQ S0/0 209.165.201.2 255.255.255.252
S0/1 172.16.255.253 255.255.255.252
Lo0 172.16.0.1 255.255.192.0
Lo1 172.16.64.1 255.255.224.0
Lo2 172.16.96.1 255.255.240.0
Lo3 172.16.112.1 255.255.248.0
Lo4 172.16.120.1 255.255.252.0
REMOTE S0/1 172.16.255.254 255.255.255.252
Objectives
■ Design a VLSM addressing scheme.
Lo0 172.16.128.1 255.255.240.0
Lo1 172.16.144.1 255.255.240.0
Lo2 172.16.160.1 255.255.240.0
Lo3 172.16.176.1 255.255.240.0
Lo4 172.16.192.1 255.255.240.0
■ Configure routers with basic configurations using your addressing scheme.
■ Configure dynamic, static, and default routing.
■ Verify connectivity and troubleshoot problems.
Equipment
The topology shown in Figure 2-17 uses 2600 series routers. This lab can be done with any combination of
1700, 2500, and 2600 series routers.
NetLab Compatibility Notes
This lab can be completed on a standard NetLab three router pod.
Task 1: Design the Addressing Scheme
You are given the address space, 172.16.0.0/16. The five loopback interfaces on HQ and five loopback
interfaces on REMOTE are used to simulate different parts of a global network. Use the following specifications
to design your addressing scheme.

Table 2-16 LAN Addressing Specifications
HQ Hosts Needed
Production LAN 16,000
Warehousing LAN 8000
Marketing LAN 4000
Management LAN 2000
Purchasing LAN 1000
REMOTE Hosts Needed
Eastern Region 4000
Northern Region 4000
Western Region 4000
Southern Region 4000
International 4000
Label the topology in Figure 2-17 with the networks and finish filling in the IP addresses in Table 2-16
with your chosen addressing scheme. Use the first IP address in each subnet for the interface address. For
the WAN link between HQ and REMOTE, assign HQ the first address.
Task 2: Cable the Topology and Basic Configuration
Step 1. Choose three routers and cable them according to the topology. You will not need any LAN
interfaces or switches for this lab. (If using NetLab, choose a three router pod).
Step 2. Configure the routers with basic configurations including interface addresses.
Task 3: Configure OSPF Routing and Default Routing
Step 1. Configure both HQ and REMOTE to use OSPF as the routing protocol. Enter the simulated
LAN subnets and the WAN link between HQ and REMOTE. Do not advertise the
209.165.201.0/30 network.
Step 2. Configure ISP with a static route pointing the 172.16.0.0/16 Address Space. Configure HQ
with a default route pointing to ISP. Configure HQ to advertise the default route to REMOTE.
Step 3. Verify HQ and REMOTE routing tables.
■ HQ should have seven directly connected routes, five OSPF routes, and one static route.
■ REMOTE should have six directly connected routes, five OSPF routes, and one OSPF E2 route.
■ Verify that REMOTE can ping the Simulated Web Server at 209.165.202.129.
Task 4: Other OSPF Configurations
Step 1. Change the OSPF hello interval to 20 seconds.
Chapter 2: Single-Area OSPF 169
Step 2. The link between HQ and REMOTE is a 1/4 T1. Change the bandwidth on both HQ and
REMOTE to match the actual link speed.
Step 3. Configure OSPF authentication with MD5 between HQ and REMOTE. Use “allrouters” as the key.

170 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 5: Verification and Documentation
Step 1. Capture the following verifications to a text file called verify.txt:
■ Ping output from REMOTE pinging the Simulated Web Server.
■ Capture show ip route on all three routers: ISP, HQ, and REMOTE.
■ Capture show ip ospf, show ip ospf neighbor, and show ip ospf interface on HQ and REMOTE.
Step 2. Capture the running configurations on all three routers to separate text files. Use the hostname
of the router to name each text file.
Step 3. Clean up the verify.txt, HQ.txt, REMOTE.txt, and ISP.txt files. Add appropriate notes to assist
in your studies.
ISP hostname ISP
!
enable secret class
!
!
ip subnet-zero
no ip domain-lookup
!
interface Loopback0
!
description Simulated Public Web Server
ip address 209.165.202.129 255.255.255.255
interface Serial0/0
!
description Link to Customer
ip address 209.165.201.1 255.255.255.252
no shutdown
ip route 172.16.0.0 255.255.0.0 Serial0/0
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous

login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
HQ hostname HQ
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host ISP 209.165.201.1
ip host REMOTE 172.16.255.254
ip host WEB 209.165.202.129
!
interface Loopback0
!
description Production LAN
ip address 172.16.0.1 255.255.192.0
interface Loopback1
!
description Warehouse LAN
ip address 172.16.64.1 255.255.224.0
interface Loopback2
!
description Marketing LAN
ip address 172.16.96.1 255.255.240.0
interface Loopback3
!
description Management LAN
ip address 172.16.112.1 255.255.248.0
interface Loopback4
!
description Purchasing LAN
ip address 172.16.120.1 255.255.252.0
interface Serial0/0
!
description Link to ISP
ip address 209.165.201.2 255.255.255.252
clockrate 64000
no shutdown
Chapter 2: Single-Area OSPF 171

172 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface Serial0/1
!
description Link to REMOTE
bandwidth 386
ip address 172.16.255.253 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 20
clockrate 64000
no shutdown
router ospf 1
!
area 0 authentication message-digest
network 172.16.0.0 0.0.63.255 area 0
network 172.16.64.0 0.0.31.255 area 0
network 172.16.96.0 0.0.15.255 area 0
network 172.16.112.0 0.0.7.255 area 0
network 172.16.120.0 0.0.3.255 area 0
network 172.16.255.252 0.0.0.3 area 0
default-information originate
ip route 0.0.0.0 0.0.0.0 Serial0/0
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
REMOTE

hostname REMOTE
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host ISP 209.165.201.1
ip host WEB 209.165.202.129
ip host HQ 172.16.255.253
!
interface Loopback0
!
description East Region
ip address 172.16.128.1 255.255.240.0
interface Loopback1
!
description North Region
ip address 172.16.144.1 255.255.240.0
interface Loopback2
!
description South Region
ip address 172.16.160.1 255.255.240.0
interface Loopback3
!
description West Region
ip address 172.16.176.1 255.255.240.0
interface Loopback4
!
description International
ip address 172.16.192.1 255.255.240.0
interface Serial0/1
!
description Link to HQ
bandwidth 386
ip address 172.16.255.254 255.255.255.252
ip ospf message-digest-key 1 md5 7 allrouters
ip ospf hello-interval 20
no shutdown
router ospf 1
area 0 authentication message-digest
network 172.16.128.0 0.0.15.255 area 0
network 172.16.144.0 0.0.15.255 area 0
network 172.16.160.0 0.0.15.255 area 0
network 172.16.176.0 0.0.15.255 area 0
network 172.16.192.0 0.0.15.255 area 0
network 172.16.255.252 0.0.0.3 area 0
Chapter 2: Single-Area OSPF 173

174 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end

CHAPTER 3
EIGRP and Troubleshooting Routing Protocols
The Study Guide portion of this chapter uses a combination of matching, fill in the blank, multiple choice,
open-ended question, and unique custom exercises to test your knowledge on the theory of EIGRP concepts,
EIGRP configuration, and basic routing protocol troubleshooting.
The Lab Exercises portion of this chapter includes all of the online curriculum labs as well as a comprehensive
lab and a challenge lab to ensure that you have mastered the practical, hands-on skills needed
about EIGRP and routing troubleshooting.

176 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
EIGRP Concepts
EIGRP is the enhanced version of the Cisco-proprietary Interior Gateway Routing Protocol (IGRP). The
speed of convergence, ease of configuration, and blending of the best of both distance vector and link-state
routing protocols make EIGRP the most powerful of IGPs. To get the absolute best of both worlds, use
EIGRP if all of your equipment is from Cisco.
The exercises in this section walk you through the terminology and concepts of EIGRP. Pay particular
attention to the similarities and differences between EIGRP and other routing protocols.
Vocabulary Exercise: Matching
Directions: Match the definition on the left with a term on the right. This exercise is not necessarily a oneto-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
However, all terms and definitions are used.
Definition
a. table that includes route entries for all destinations
that the router has learned
b. a route selected as the primary route to reach
a destination
c. table that ensures bidirectional communication
between each of the directly connected
neighbors
d. a backup route kept in the topology table in
case the primary route goes down
e. used by EIGRP to discover, verify, and rediscover
neighbor routers
f. a route that is in a reachable and operational
status
g. guarantees loop-free operation at every
instant throughout a route computation and
allows all devices involved in a topology
change to synchronize at the same time
h. table in which EIGRP places the routes it
chooses from the topology table as the best
(successor) routes to a destination
i. status of a route that has no feasible successors
yet; router is waiting on replies from
EIGRP routers
j. used by EIGRP to guarantee ordered delivery
of EIGRP packets to all neighbors
k. used when a router discovers a new neighbor
l. used when a router needs specific information
from one or all of its neighbors
Term
d feasible successor
e hello packets
g Diffusing Update Algorithm
j Reliable Transport Protocol
c neighbor table
k update packet
a topology table
l query packet
b successor
h routing table
i active state
f passive state

Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
IGRP and EIGRP are compatible with each other, which provides seamless interoperability between the
two processes. EIGRP uses metric calculations similar to those used by IGRP, and EIGRP supports the
same unequal-cost path load balancing as IGRP does.
Although the metric (bandwidth and delay by default) is the same for both IGRP and EIGRP, the weight
assigned to the metric is 256 times greater for EIGRP. That is because EIGRP uses a metric that is 32 bits
long, and IGRP uses a 24-bit metric. By multiplying or dividing by 256, EIGRP can easily exchange information
with IGRP.
IGRP has a maximum hop count of 255. EIGRP has a maximum hop count of 224. By default, the Cisco
IOS limits the hop count for EIGRP limited to 100 as displayed by the show ip protocols command. This
is more than adequate to support the largest, properly designed internetworks.
EIGRP’s convergence technology employs the Diffusing Update Algorithm (DUAL), which guarantees
loop-free operation at every instant throughout a route. Routers that are not affected by topology changes
are not involved in recomputations.
Redistribution, the sharing of routes, is automatic between IGRP and EIGRP as long as both processes use
the same autonomous system number.
Like OSPF, EIGRP maintains three tables for use with its computations. These tables include the neighbor
table (called the adjacency database in OSPF), the topology table (called the link-state database in OSPF),
and the routing table (called the forwarding database in OSPF).
The following are some additional features of EIGRP:
■ EIGRP converges rapidly on network topology changes. In some situations, convergence can be
almost instantaneous. EIGRP stores backup routes, called feasible successors, so that it can quickly
adapt to these alternate routes if the primary route, called the successor, becomes unavailable. If no
backup route exists, then EIGRP sends a query packet to its neighbors to discover an alternate route.
■ During normal operations when the network topology is fully converged, only hello packets are sent
to neighbors. These packets are also used to establish neighbor adjacencies.
■ EIGRP supports automatic route summarization at classful network boundaries. But it can be manually
configured to advertise on arbitrary network boundaries to reduce the size of routing tables.
■ EIGRP uses its own Layer 4 protocol called the Reliable Transport Protocol. Because EIGRP provides
support for multiple routed protocols, including AppleTalk (AT) and Internetwork Packet Exchange
(IPX), it must be protocol independent. That means it cannot depend on TCP for reliability services.
EIGRP Packet Type Exercise
Like OSPF, EIGRP relies on different types of packets to maintain its tables and establish relationships
with neighbor routers. Complete the missing elements that follow by filling in appropriate words or phrases.
When given the choice, circle whether the packet is reliable or unreliable and whether it is unicast or
multicast.
Hello packets:
■ (Reliable/Unreliable) (unicast/multicast) sent to the address 224.0.0.10 to discover and maintain
neighbors; contains the router’s neighbor table
■ Default hello interval depends on the bandwidth:
— ≤ 1.544 Mbps = 60 sec. hello interval (180 sec. holdtime)
— > 1.544 Mbps = 5 sec. hello interval (15 sec. holdtime)
Chapter 3: EIGRP and Troubleshooting Routing Protocols 177

178 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Update packets. Sent (reliably/unreliably), there are two types:
■ (Unicast/Multicast) to new neighbor discovered; contains routing table
■ (Unicast/Multicast) to all neighbors when topology changes
Query packets. Queries are (unicast/multicast) (reliably/unreliably) during route recomputation, asking
neighbors for a new successor to a lost route.
Reply packets. Neighbors (unicast/multicast) a reply to a query of whether or not they have a route.
Acknowledgement packets. “Dataless” (unicast/multicast) packet that acknowledges the receipt of a packet
that was sent reliably.
EIGRP Configuration
Now that you have a firm grasp of EIGRP concepts, it is time to learn how to configure EIGRP. The exercise
in this section takes you step-by-step through an EIGRP configuration.
Learn the EIGRP Commands Exercise
Document the command syntax, including router prompt, to configure the EIGRP routing process.
Router(config)#router eigrp autonomous-system-number
True or False: All routers in an area must have the same autonomous-system-number.
True. The autonomous system number is used to identify all routers that will be participating in this
EIGRP routing process. It must match for all routers in the system.
Like the process-id in OSPF, the value for autonomous-system-number can be any number between 1 and
65535 as long as it does not have to be registered with IANA.
Refer to Figure 3-1. In the space provided, document the correct commands, including router prompt, to
configure RTA to advertise all directly connected networks in EIGRP.
Figure 3-1 RTA EIGRP Configuration
172.16.64.0/20
172.16.80.0/20
172.16.96.0/20
172.16.112.0/20
10.0.0.8/30
RTC
T1
S0/0
DCE
172.16.0.0/18
RTA
EIGRP
100
128kbps
T1
10.0.0.0/30
S0/1
10.0.0.4/30 S0/0
DCE
RTB
172.16.128.0/19
172.16.160.0/19
172.16.192.0/19
172.16.224.0/19

RTA(config)#router eigrp 100
RTA(config-router)#network 10.0.0.0
RTA(config-router)#network 172.16.0.0
In Figure 3-1, RTB and RTC are distribution routers for several networks. Each router has six networks
attached: two WANs and four simulated LANs. If configuring OSPF, you would have to enter each network
in the routing process. But for EIGRP, the configuration is greatly simplified. You need to enter only
the classful networks. Therefore, the EIGRP configuration for RTB and RTC is identical to that of RTA. In
the space provided, document the correct commands, including router prompt, to configure RTB and RTC
to advertise all directly connected networks in EIGRP.
RTB(config)#router eigrp 100
RTB(config-router)#network 10.0.0.0
RTB(config-router)#network 172.16.0.0
!
RTC(config)#router eigrp 100
RTC(config-router)#network 10.0.0.0
RTC(config-router)#network 172.16.0.0
In Figure 3-1, notice that the WAN links are labeled with the contracted bandwidth. Because EIGRP calculates
the metric using bandwidth and delay, you need to configure the links for the correct bandwidth.
Assume that the default bandwidth for the three routers is 1544 kbps. Document the commands, including
router prompt, to configure RTB and RTC with the correct bandwidth.
RTB(config)#interface serial 0/0
RTB(config-if)#bandwidth 128
!
RTC(config)#interface serial 0/0
RTC(config-if)#bandwidth 128
Chapter 3: EIGRP and Troubleshooting Routing Protocols 179
The following output was sent to the console by the IOS when RTA and RTB established a new adjacency.
Document the command, including router prompt, that you need to configure to have this message sent to
the console on RTA.
RTA#
00:24:44: %DUAL-5-NBRCHANGE: IP-EIGRP 100: Neighbor 10.0.0.2 (Serial0/1) is up:
new adjacency
RTA(config-router)#eigrp log-neighbor-changes
Figure 3-1 has discontiguous subnets. Subnets of the 10.0.0.0 classful network separate subnets of the
172.16.0.0 classful network. As the configuration stands now, no router can send traffic to any of the
LANs connected to another router. The routing table for RTA follows. Document the command, including
router prompt, that must be configured on all three routers before all subnets will be reachable from anywhere
in the network.
RTA#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

180 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.16.0.0/16 is a summary, 00:23:16, Null0
C 172.16.0.0/18 is directly connected, FastEthernet0/0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:23:20, Null0
C 10.0.0.0/30 is directly connected, Serial0/1
RTA(config-router)#no auto-summary
Note: Now is a good time to complete Curriculum Lab 3-1: Configuring EIGRP Routing (3.2.1).
The output that follows shows the current routing table for RTA with automatic summarization disabled,
and then shows the same routing table after manual summarization. Even in this simulated network, the
table is rather large. In production networks, this table could be huge. Unlike single-area OSPF configurations,
EIGRP provides a method to manually summarize subnets within the same address space into one
route table entry. Document the commands necessary to configure RTB and RTC to manually summarize
the simulated LANs into one advertisement.
RTA routing table before manual summarization:
RTA#show ip route
(output omitted)
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 9 subnets, 3 masks
D 172.16.160.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.128.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.224.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.192.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
C 172.16.0.0/18 is directly connected, FastEthernet0/0
D 172.16.112.0/20 [90/2297856] via 10.0.0.9, 00:00:29, Serial0/0
D 172.16.96.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
D 172.16.80.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
D 172.16.64.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
10.0.0.0/30 is subnetted, 3 subnets
C 10.0.0.8 is directly connected, Serial0/0
C 10.0.0.0 is directly connected, Serial0/1
D 10.0.0.4 [90/21024000] via 10.0.0.9, 00:00:30, Serial0/0
[90/21024000] via 10.0.0.2, 00:00:30, Serial0/1
RTA routing table after manual summarization:
RTA#show ip route
(output omitted)
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
D 172.16.128.0/17 [90/2297856] via 10.0.0.2, 00:00:36, Serial0/1

C 172.16.0.0/18 is directly connected, FastEthernet0/0
D 172.16.64.0/18 [90/2297856] via 10.0.0.9, 00:02:43, Serial0/0
10.0.0.0/30 is subnetted, 3 subnets
C 10.0.0.8 is directly connected, Serial0/0
C 10.0.0.0 is directly connected, Serial0/1
D 10.0.0.4 [90/21024000] via 10.0.0.9, 00:00:36, Serial0/0
[90/21024000] via 10.0.0.2, 00:00:36, Serial0/1
RTB(config)#interface s0/0
RTB(config-if)#ip summary-address eigrp 100 172.16.128.0 255.255.128.0
RTB(config-if)#interface s0/1
RTB(config-if)#ip summary-address eigrp 100 172.16.128.0 255.255.128.0
!
RTC(config-if)#interface s0/0
RTC(config-if)#ip summary-address eigrp 100 172.16.64.0 255.255.192.0
RTC(config-if)#interface s0/1
RTC(config-if)#ip summary-address eigrp 100 172.16.64.0 255.255.192.0
Instructor Note: Configuring manual summarization for EIGRP is an opportunity to reinforce the route summarization
skills taught in Chapter 1, “Introduction to Classless Routing.”
Troubleshooting Routing Protocols
Learning how to troubleshoot network problems and misconfigurations is paramount to your CCNA skill
set. Not only will this skill save you countless hours on the job, your ability to problem solve will be thoroughly
tested on the CCNA exam. The only way to develop troubleshooting or problem-solving skills is
by practicing. The more “hands on” experience you gain from cabling and configuring networks, the more
problems you will run across and solve.
By far, the most common errors occur at Layer 1. Always check your physical layer first when a problem
occurs. Then, work your way up the layers. Too often, students issue the command show run to find a
problem. Rarely is this the best or most efficient method of troubleshooting your network. In addition, on
production networks the running configuration can span many pages. Learn the show and debug commands.
Develop an understanding of what the output from these commands means. Not only will this skill
better assist you in troubleshooting your network configurations, you will be better prepared for the troubleshooting
scenarios you encounter on the CCNA exam.
In the following exercises, you will document a problem-solving flow chart and then work through show
and debug commands for RIP, EIGRP, and OSPF. The Internet Research Exercise asks you to research the
fields of an IP packet header.
Problem-Solving Cycle
Chapter 3: EIGRP and Troubleshooting Routing Protocols 181
In the space provided, draw a flow chart showing a generic problem-solving cycle that starts with “identify
problem” and ends with “document problem and solution.” Your flow chart should have no less than six
steps, but it can have more.

182 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 3-2 Problem-Solving Cycle
Identify
Problem
Troubleshooting RIP
The most common problem found in RIP that prevents RIP routes from being advertised is discontiguous
subnets because RIP Version 1 does not support VLSM. First, make sure both Layer 1 and Layer 2 are
functioning. Then, use the commands reviewed in this exercise to verify and troubleshoot the network.
What command generates the following output?
Router#show ip route
Gather/
Analyze
Data
Solution
Resolve
Problem?
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 192.168.1.253 to network 0.0.0.0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
R 192.168.1.64/26 [120/1] via 192.168.1.246, 00:00:03, Serial0/1
C 192.168.1.0/26 is directly connected, FastEthernet0/0
R 192.168.1.248/30 [120/1] via 192.168.1.246, 00:00:03, Serial0/1
[120/1] via 192.168.1.253, 00:00:07, Serial0/0
C 192.168.1.252/30 is directly connected, Serial0/0
C 192.168.1.244/30 is directly connected, Serial0/1
R 192.168.1.128/26 [120/1] via 192.168.1.253, 00:00:08, Serial0/0
R* 0.0.0.0/0 [120/9] via 192.168.1.253, 00:00:02, Serial0/0
Using the preceding output, answer the following questions.
No
Yes
Document
Problem and
Solution
List Possible
Solutions
Test Most
Likely
Solution

In the shaded entry for 192.168.1.128/26, what does the 120 mean in the [120/1] portion of the entry?
Administrative distance
What does the 1 mean?
The metric; number of hops to the destination
Why are there two entries to the 192.168.1.248/30 network?
RIP will install up to four equal-cost routes to the destination.
How many subnets and masks are used in the 192.168.1.0/24 address space?
Six subnets and two masks
What command generates the following output?
Router#show ip protocols
Routing Protocol is “rip”
Sending updates every 30 seconds, next due in 15 seconds
Invalid after 180 seconds, hold down 180, flushed after 240
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Redistributing: rip
Default version control: send version 2, receive version 2
Interface Send Recv Triggered RIP Key-chain
FastEthernet0/0 2 2
Serial0/0 2 2
Serial0/1 2 2
Automatic network summarization is not in effect
Maximum path: 6
Routing for Networks:
192.168.1.0
Routing Information Sources:
Gateway Distance Last Update
192.168.1.253 120 00:00:17
192.168.1.246 120 00:00:12
Distance: (default is 120)
Using the preceding output, answer the following questions.
How many routers are advertising RIP routes to this router?
Two; listed under “Routing Information Sources”
How many equal-cost routes to the same destination can this router use (not the default)?
Six; shown as “Maximum path”
What are the timers for RIP:
■ Update: 30 seconds
■ Holddown: 180 seconds
■ Invalid: 180 seconds
■ Flushed: 240 seconds
Chapter 3: EIGRP and Troubleshooting Routing Protocols 183

184 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
What command generates the following output?
Router#debug ip rip
00:29:04: RIP: received v2 update from 192.168.1.253 on Serial0/0
00:29:04: 192.168.1.64/26 via 0.0.0.0 in 2 hops
00:29:04: 192.168.1.128/26 via 0.0.0.0 in 1 hops
00:29:04: 192.168.1.248/30 via 0.0.0.0 in 1 hops
00:29:05: RIP: sending v2 update to 224.0.0.9 via FastEthernet0/0 (192.168.1.1)
00:29:05: RIP: build update entries
00:29:05: 192.168.1.64/26 via 0.0.0.0, metric 2, tag 0
00:29:05: 192.168.1.128/26 via 0.0.0.0, metric 2, tag 0
00:29:05: 192.168.1.244/30 via 0.0.0.0, metric 1, tag 0
00:29:05: 192.168.1.248/30 via 0.0.0.0, metric 2, tag 0
00:29:05: 192.168.1.252/30 via 0.0.0.0, metric 1, tag 0
00:29:05: RIP: sending v2 update to 224.0.0.9 via Serial0/0 (192.168.1.254)
00:29:05: RIP: build update entries
00:29:05: 192.168.1.0/26 via 0.0.0.0, metric 1, tag 0
00:29:05: 192.168.1.64/26 via 0.0.0.0, metric 2, tag 0
00:29:05: 192.168.1.244/30 via 0.0.0.0, metric 1, tag 0
Using the preceding output, answer the following questions.
How many RIP neighbors does this router have?
From the output, only one, at 192.168.1.253
Notice that this router sent two updates. How many routes did RIP advertise out FastEthernet0/0?
Five
How many routes did RIP advertise out Serial0/0?
Three
What routes that were advertised out Fa0/0 were not advertised out S0/0?
192.168.1.252/30 and 192.168.1.128/26
Why do you think these routes were not advertised out the S0/0 interface?
Because split-horizon prevents a router from sending out updates about networks to another router if the
router receiving the update is the one that originally advertised the route. In this case, the route heard
about the 192.168.1.128/26 network from the router it is sending the update to. In addition, if two routers
share a network, then neither router needs to advertise the route to the other router. That is the case with
the 192.168.1.252/30 network.
Is it necessary to advertise out the Fast Ethernet interface? If not, what can you do to stop advertisements?
If so, why?
The only reason to advertise out the Fast Ethernet interface is if there is another RIP router that needs
updates out that interface. Otherwise, it is best to turn off updates on Fast Ethernet interfaces by using the
passive-interface command.

Troubleshooting EIGRP
Normal EIGRP operation is stable, efficient in bandwidth utilization, and relatively simple to monitor and
troubleshoot. Make sure your Layer 1 and Layer 2 are functioning. Then use the following commands to
verify and troubleshoot the network.
What command generates the following output?
Router#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
D 172.16.128.0/17 [90/2297856] via 10.0.0.2, 00:00:19, Serial0/1
C 172.16.0.0/18 is directly connected, FastEthernet0/0
D 172.16.64.0/18 [90/2297856] via 10.0.0.9, 00:00:19, Serial0/0
10.0.0.0/30 is subnetted, 3 subnets
C 10.0.0.8 is directly connected, Serial0/0
C 10.0.0.0 is directly connected, Serial0/1
D 10.0.0.4 [90/21024000] via 10.0.0.2, 00:00:19, Serial0/1
[90/21024000] via 10.0.0.9, 00:00:19, Serial0/0
Using the preceding output, answer the following questions.
In the shaded entry for 172.16.128.0/17, what does the 90 mean in the [90/2297856] portion of the entry?
Administrative distance
What does the 2297856 mean?
The metric; it is a value calculated by DUAL that takes into consideration bandwidth and delay.
Why are there two entries to the 10.0.0.4/30 network?
By default, EIGRP installs up to four equal-cost routes to the destination.
How many subnets and masks are used in the 192.168.1.0/24 address space?
Six subnets and two masks
What command generates the following output?
Router#show ip protocols
Routing Protocol is “eigrp 100”
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Default networks flagged in outgoing updates
Default networks accepted from incoming updates
EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0
EIGRP maximum hopcount 100
Chapter 3: EIGRP and Troubleshooting Routing Protocols 185

186 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
EIGRP maximum metric variance 1
Redistributing: eigrp 100
Automatic network summarization is not in effect
Maximum path: 5
Routing for Networks:
10.0.0.0
172.16.0.0
Routing Information Sources:
Gateway Distance Last Update
10.0.0.9 90 00:00:53
10.0.0.2 90 00:00:53
Distance: internal 90 external 170
Using the preceding output, answer the following questions.
How many routers are advertising EIGRP routes to this router?
Two; listed under “Routing Information Sources”
How many equal-cost routes to the same destination can this router use (not the default)?
Five; shown as “Maximum path”
The K1 and K3 values in the metric weight have a value of 1 each. What are these values for?
In the EIGRP metric formula used by DUAL, the value for bandwidth (K1) and the value for delay (K3)
are given the same proportional weight.
The K2, K4, and K5 values are all 0. What do these values represent and why are they 0?
They represent reliability, load, and MTU, which can also be configured as part of the EIGRP metric. By
default, these values are set to 0 and only bandwidth and delay are evaluated.
What command generates the following output?
Router#show ip eigrp neighbors
H Address Interface Hold Uptime SRTT RTO Q Seq Type
(sec) (ms) Cnt Num
1 10.0.0.9 Se0/0 11 00:23:21 24 200 0 4
0 10.0.0.2 Se0/1 10 00:23:35 32 200 0 8
What command generates the following output?
Router#show ip eigrp topology
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 10.0.0.8/30, 1 successors, FD is 2169856
via Connected, Serial0/0
P 10.0.0.0/30, 1 successors, FD is 2169856
via Connected, Serial0/1
P 10.0.0.4/30, 2 successors, FD is 21024000
via 10.0.0.2 (21024000/20512000), Serial0/1
via 10.0.0.9 (21024000/20512000), Serial0/0
P 172.16.128.0/17, 1 successors, FD is 2297856
via 10.0.0.2 (2297856/128256), Serial0/1

P 172.16.0.0/18, 1 successors, FD is 28160
via Connected, FastEthernet0/0
P 172.16.64.0/18, 1 successors, FD is 2297856
via 10.0.0.9 (2297856/128256), Serial0/0
What command generates the following output?
Router#show ip eigrp traffic
Hellos sent/received: 1044/696
Updates sent/received: 9/9
Queries sent/received: 0/0
Replies sent/received: 0/0
Acks sent/received: 7/7
Input queue high water mark 1, 0 drops
SIA-Queries sent/received: 0/0
SIA-Replies sent/received: 0/0
What command generates the following output?
Router#debug ip eigrp
IP-EIGRP: Processing incoming UPDATE packet
IP-EIGRP: Ext 192.168.3.0 255.255.255.0 M 386560 – 256000 130560 SM 360960 – 256000
104960
IP-EIGRP: Ext 192.168.0.0 255.255.255.0 M 386560 – 256000 130560 SM 360960 – 256000
104960
IP-EIGRP: Ext 192.168.3.0 255.255.255.0 M 386560 – 256000 130560 SM 360960 – 256000
104960
IP-EIGRP: 172.69.43.0 255.255.255.0, - do advertise out Ethernet0/1
IP-EIGRP: Ext 172.68.43.0 255.255.255.0 metric 371200 – 25600 115200
IP-EIGRP: 192.135.246.0 255.255.255.0, - do advertise out Ethernet0/1
IP-EIGRP: Ext 192.135.246.0 255.255.255.0 metric 46310656 – 45714176 596480
IP-EIGRP: 172.69.40.0 255.255.255.0, - do advertise out Ethernet0/1
IP-EIGRP: Ext 172.68.40.0 255.255.255.0 metric 2272256 – 1657856 614400
IP-EIGRP: 192.135.245.0 255.255.255.0, - do advertise out Ethernet0/1
IP-EIGRP: Ext 192.135.245.0 255.255.255.0 metric 40622080 – 40000000 622080
IP-EIGRP: 192.135.244.0 255.255.255.0, - do advertise out Ethernet0/1
Troubleshooting OSPF
The majority of problems encountered with OSPF relate to the formation of adjacencies and the synchronization
of the link-state databases.
Make sure your Layer 1 and Layer 2 are functioning. Then use the following commands to verify and
troubleshoot the network.
What command generates the following output?
Router#show ip route
Chapter 3: EIGRP and Troubleshooting Routing Protocols 187
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route

188 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Gateway of last resort is 192.168.1.245 to network 0.0.0.0
192.168.1.0/24 is variably subnetted, 6 subnets, 2 masks
C 192.168.1.64/26 is directly connected, FastEthernet0/0
O 192.168.1.0/26 [110/65] via 192.168.1.245, 00:00:06, Serial0/1
C 192.168.1.248/30 is directly connected, Serial0/0
O 192.168.1.252/30 [110/128] via 192.168.1.245, 00:00:06, Serial0/1
C 192.168.1.244/30 is directly connected, Serial0/1
O 192.168.1.128/26 [110/129] via 192.168.1.245, 00:00:06, Serial0/1
O*E2 0.0.0.0/0 [110/1] via 192.168.1.245, 00:00:07, Serial0/1
Using the preceding output, answer the following questions.
In the entry for 192.168.1.0/26, what does the 110 mean in the [110/65] portion of the entry?
Administrative distance
What does the 65 mean?
The metric; it is the accumulated cost of the route based on the 108/bps formula.
How many subnets and masks are used in the 192.168.1.0/24 address space?
Six subnets and two masks
What does O*E2 stand for and what does it mean?
This is an external type 2 OSPF route. The * means that it is a candidate for default routing. The O and E2
identify this as an external type 2 OSPF route, which means that the cost is not accumulated as the route is
propagated throughout the OSPF area.
What command generates the following output?
Router#show ip protocols
Routing Protocol is “ospf 1”
Outgoing update filter list for all interfaces is not set
Incoming update filter list for all interfaces is not set
Router ID 209.165.202.129
It is an autonomous system boundary router
Redistributing External Routes from,
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
Maximum path: 4
Routing for Networks:
192.168.1.0 0.0.0.63 area 0
192.168.1.244 0.0.0.3 area 0
192.168.1.252 0.0.0.3 area 0
Routing Information Sources:
Gateway Distance Last Update
209.165.202.129 110 00:08:10
192.168.1.249 110 00:08:10
192.168.1.253 110 00:08:10
Distance: (default is 110)
Notice in the preceding output the line that states, “It is an autonomous system boundary router.” What
does this mean?

It means that this router is running at least two different routing processes. One of them is OSPF. In this
case, the other is a static default route. This can be deduced from the “Routing Information Sources” portion
of the output. Notice that the gateway 209.165.202.129 is not listed in the “Routing for Networks”
portion of the output. This means that 209.165.202.129 is not part of OSPF but is being routed inside
OSPF from another source. In this case, the default-information originate command along with the ip
route command has made this router an ASBR (autonomous system boundary router).
What command generates the following output?
Router#debug ip ospf events
00:09:46: OSPF: Rcv hello from 192.168.1.249 area 0 from Serial0/1 192.168.1.246
00:09:46: OSPF: Mismatched hello parameters from 192.168.1.246
00:09:46: OSPF: Dead R 160 C 120, Hello R 40 C 40
00:10:26: OSPF: Rcv hello from 192.168.1.253 area 0 from Serial0/0 192.168.1.253
00:10:26: OSPF: End of hello processing
00:10:26: OSPF: Rcv hello from 192.168.1.249 area 0 from Serial0/1 192.168.1.246
00:10:26: OSPF: Mismatched hello parameters from 192.168.1.246
00:10:26: OSPF: Dead R 160 C 120, Hello R 40 C 40
00:11:06: OSPF: Rcv hello from 192.168.1.253 area 0 from Serial0/0 192.168.1.253
00:11:06: OSPF: End of hello processing
00:11:06: OSPF: Rcv hello from 192.168.1.249 area 0 from Serial0/1 192.168.1.246
00:11:06: OSPF: Mismatched hello parameters from 192.168.1.246
00:11:06: OSPF: Dead R 160 C 120, Hello R 40 C 40
00:11:46: OSPF: Rcv hello from 192.168.1.253 area 0 from Serial0/0 192.168.1.253
00:11:46: OSPF: End of hello processing
00:11:46: OSPF: Rcv hello from 192.168.1.249 area 0 from Serial0/1 192.168.1.246
00:11:46: OSPF: Mismatched hello parameters from 192.168.1.246
00:11:46: OSPF: Dead R 160 C 120, Hello R 40 C 40
00:11:46: OSPF: 192.168.1.249 address 192.168.1.246 on Serial0/1 is dead
00:11:46: %OSPF-5-ADJCHG: Process 1, Nbr 192.168.1.249 on Serial0/1 from FULL to
DOWN, Neighbor Down: Dead timer expired
From the preceding command output, what is the problem?
In OSPF configurations, hello and dead intervals must be the same for all OSPF neighbors. In the output
shown, you interpret the line Dead R 160 C 120, Hello R 40 C 40 as follows: dead received, 160 seconds;
dead configured 120 seconds; hello received, 40 seconds; hello configured, 40 seconds.
In this case, the dead interval has been changed from 160, which was four times the hello, to 120. The reason
why you know that it has just been changed is that the local router had established adjacency with
192.168.1.249. It took the configured 120-second dead interval before the adjacency state with the neighbor
to go from FULL to DOWN.
What command would fix the “mismatch of hello parameters”?
Router(config-if)#ip ospf dead-interval 160
or
Router(config-if)#no ip ospf dead-interval 120
Chapter 3: EIGRP and Troubleshooting Routing Protocols 189

190 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Suppose that after you fixed the mismatch problem, you wanted to watch the processing of packets as the
two neighbors re-establish adjacency. What command generated the following output?
Router#debug ip ospf packets
00:24:26: OSPF: rcv. v:2 t:1 l:44 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B91532F from Serial0/1
00:24:29: OSPF: rcv. v:2 t:2 l:32 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915330 from Serial0/1
00:24:29: OSPF: rcv. v:2 t:2 l:112 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915331 from Serial0/1
00:24:29: OSPF: rcv. v:2 t:2 l:32 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915332 from Serial0/1
00:24:29: OSPF: rcv. v:2 t:2 l:32 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915333 from Serial0/1
00:24:30: OSPF: rcv. v:2 t:4 l:112 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915335 from Serial0/1
00:24:32: OSPF: rcv. v:2 t:5 l:44 rid:192.168.1.249
aid:0.0.0.0 chk:0 aut:2 keyid:1 seq:0x2B915337 from Serial0/1
In the following table, fill in the description for each field shown in the preceding output.
Note: You may have to search Cisco.com to find the answers.
Field Description
v: OSPF version
t: OSPF packet type; possible packet types are as follows:
1: Hello
2: Data description
3: Link-state request
4: Link-state update
5: Link-state acknowledgment
l: OSPF packet length in bytes
rid: OSPF router ID
aid: OSPF area ID
chk: OSPF checksum
aut: OSPF authentication type; possible authentication types are as follows:
0: No authentication
1: Simple password
2: MD5
auk: OSPF authentication key
keyid: MD5 key ID
seq: Sequence number

Internet Research Exercise
The CCNA objectives cover all of the layers of the OSI model to some extent. Some layers are less important
than others to your studies. For example, the presentation and session layers can be thought of as
belonging to the application layer, as shown when comparing the TCP/IP model and the OSI model side
by side. The most important layer of the OSI model for CCNA candidates is the network layer. And the
most important protocol of the network layer is the Internet Protocol (IP).
Your assignment is to research IP to discover detailed information about the structure of its packet header.
You can use any trusted Internet resource, but the original source is the RFC. Make sure you list your
sources in the place provided at the end of this exercise.
The IP Packet Header
In Figure 3-3, label all the fields of the IP packet header.
Figure 3-3 IP Packet Header
A B C D
E F G
H I J
K
L
Version
Field Descriptions
Describe in as much detail as possible the purpose of each field in the IP packet header.
Field A Version
Time to Live
Header
Length
This field identifies the IP version, which is currently version 4. So, the bit value is 0100 in this field. The
next version is version 6. There are no other versions.
Field B Header Length
Type of Service or
Differentiated
Service
Chapter 3: EIGRP and Troubleshooting Routing Protocols 191
Total Length
Identifier Flags
Fragment Offset
Protocols
M N
Options
32 Bits
8 8 8 8
Source Address
Destination Address
Header Checksum
Padding
This field specifies in 32-bit words the length of this header, which is five or 0101 when no options are
specified. This field’s value can be as large as 1111 or 15, meaning the header can be a maximum of 15
32-bit words or 60 octets.

192 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Field C Type of Service (TOS) or Differentiated Service
This 8-bit field can be broken down into two parts: Precedence and TOS. The first 3 bits specify the
Precedence value (e.g. routine-0, priority-1, immediate-2, etc.); 4th bit specifies minimal delay; 5th bit
specifies maximize throughput; 6th bit specifies maximize reliability; 7th bit specifies minimize monetary
costs; 8th bit is currently unused. Although this field is not commonly used and is usually set to all zeros,
the Precedence bits are occasionally used for QoS applications.
Field D Total Length
This field is a 16-bit number specifying the total length of the packet (header + data) in bytes; can be up to
65,535 bytes. By subtracting the header length for this value, you can determine the size of the payload.
Field E Identifier
This field is used to identify the fragments of one datagram from those of another. The originating protocol
module of an Internet datagram sets the Identifier field to a value that must be unique for that sourcedestination
pair and protocol for the time the datagram will be active in the Internet system. The originating
protocol module of a complete datagram sets the MF bit to 0 and the Fragment Offset field to 0.
Field F Flags
These 3 bits indicate whether the packet can be fragmented and whether it has more fragments coming.
The 3 bits are as follows:
■ 1st bit: Reserved (unused)
■ 2nd bit: Fragment? 1=no, 0=yes
■ 3rd bit: More Fragments Coming? 0=no, 1=yes
Field G Fragment Offset
This is a byte count from the beginning of the original packet so that the destination knows where to place
this particular fragment when reconstructing the packet. If a router’s interface is set to a maximum transmission
unit that is smaller than the sent packet, then it will be fragmented by the router. However, if the
Do Not Fragment bit is set in the Flag field, then the packet will be dropped and an ICMP message will be
sent to the source.
Field H Time to Live
This 8-bit field helps prevent routing loops. This field is set with a certain number when the packet is first
encapsulated at the source. Each router along the path from the source to the destination decrements this
field. If this field reaches 0 before the packet reaches the destination, then the packet is dropped and an
ICMP messages is sent to the source. The trace utility uses this field to trace a route to a specified destination.
Field I Protocols
Also called Service Access Point (SAP), the Protocol field identifies the upper-layer protocol that the data
packet is destined for. A few of the values of this field are shown in the following table:

Protocol Value Network Layer Protocol
1 ICMP
6 TCP
17 UDP
88 IGRP
89 OSPF
Instructor Note: Although ICMP is identified by the number 1, it is not an upper-layer protocol, but operates in the
network layer. An ICMP packet is encapsulated with an IP header.
Field J Header Checksum
This field is used to check the integrity of the bits in the header. Because each router decrements the TTL
field, this checksum must be recalculated at each hop on the way to the destination.
Field K Source Address
This field is the 32-bit IP address for the source of the packet.
Field L Destination Address
This field is the 32-bit IP address for the destination of the packet.
Field M Options
IP options can be a number of things. If the options in this field do not extend the full 32 bits of this sixth
32-bit word, then padding is added. The data must begin on a new 32-bit word boundary.
Field N Padding
If necessary, the source will add zeros to the end of the last 32-bit word in the packet header to ensure that
the header always ends on a 32-bit word.
Sources
Chapter 3: EIGRP and Troubleshooting Routing Protocols 193
Check student sources to see if they are legitimate. “RFC 791 Internet Protocol” should be listed. For the
sample answers here, the RFC was used as well as the Cisco Press title Routing TCP/IP, Volume 1, Second
Edition, pp. 7-16. The website http://www.networksorcery.com was also consulted.

194 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Lab Exercises
Command Reference
In the table that follows, record the command, including the correct router prompt, that fits the description.
Fill in any blanks with the appropriate missing information.
Command Description
Router(config)#router eigrp 100 Turns on the EIGRP process.
100 is the autonomous system (AS) number,
which can be a number between 1 and 65535.
All routers in the same AS must use the same
AS number.
Router(config-router)#eigrp log-neighbor-changes Logs any changes to an EIGRP neighbor
adjacency.
Router(config-router)#no auto-summary Turns off the automatic summarization of
networks at classful boundaries.
Router(config-if)#bandwidth 128 Changes the bandwidth of an interface to
128 kbps.
Router(config-if)#ip summary-address Enables manual summarization on this specific
eigrp 100 10.10.0.0 255.255.0.0 interface for the 10.10.0.0/16 address space.
Router#show ip eigrp neighbors Displays a neighbor table.
Router#show ip eigrp neighbors detail Displays a detailed neighbor table.
Router#show ip eigrp interface Displays EIGRP information for each interface.
Router#show ip eigrp topology Displays the topology table. This command
shows you where your feasible successors are.
Router#show ip eigrp traffic Displays the number and type of packets sent
and received.
Router#debug eigrp fsm Displays events/actions related to the DUAL
FSM.
Router#debug eigrp packet Displays events/actions related to EIGRP packets.
Router#debug eigrp neighbor Displays events/actions related to EIGRP neighbors.

Curriculum Lab 3-1: Configuring EIGRP Routing (3.2.1)
Figure 3-4 Topology for Lab 3-1
Table 3-1 Lab Equipment Configuration: Part I
Router Designation Router Name Routing Protocol Network Statements
Router 1 Paris EIGRP 192.168.3.0
192.168.2.0
Router 2 Warsaw EIGRP 192.168.1.0
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 3-2 Lab Equipment Configuration: Part II
Chapter 3: EIGRP and Troubleshooting Routing Protocols 195
Straight-Through Cable
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable
192.168.2.0
Router IP Host Fast Ethernet 0 Interface Serial 0 Address/ Loopback 0
Designation Table Entry Address/ Type Subnet Mask Subnet Mask
Subnet Mask Serial 0 Address/
Router 1 Warsaw 192.168.3.1/24 DCE 192.168.2.1/30 192.168.0.2/24
Router 2 Paris 192.168.1.1/24 DTE 192.168.2.2/30 No address
The interface type and address/subnet mask for the serial 1 interface on both routers is not applicable for
this lab.

196 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Set up an IP addressing scheme for the network.
■ Configure and verify EIGRP routing.
Background/Preparation
Cable a network that is similar to the one in Figure 3-4. You can use any router that meets the interface
requirements in Figure 3-4 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A, “Router Interface Summary Chart,” to correctly specify the interface identifiers
based on the equipment in your lab. The 1721 series routers produced the configuration output in
this lab. Another router might produce slightly different output. You should execute the following steps on
each router unless you are specifically instructed otherwise. Start a HyperTerminal session.
Implement the procedure that is documented in Appendix C, “Erasing and Reloading the Router,” on all
routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname as shown in the chart. Then,
configure the console, virtual terminal, and enable passwords. Next, configure the interfaces according to
Table 3-2. Finally, configure the IP hostnames. If you have problems configuring the router basics, refer to
Lab 1-2, “Review of Basic Router Configuration with RIP.”
Note: Do not configure the routing protocol until you are specifically told to.
PARIS
Router>enable
Router#configure terminal
Router(config)#hostname PARIS
PARIS(config)#enable secret class
PARIS(config)#line console 0
PARIS(config-line)#password cisco
PARIS(config-line)#login
PARIS(config-line)#line vty 0 4
PARIS(config-line)#password cisco
PARIS(config-line)#login
PARIS(config-line)#exit
PARIS(config)#interface serial 0
PARIS(config-if)#ip address 192.168.2.1 255.255.255.252
PARIS(config-if)#clock rate 64000
PARIS(config-if)#no shutdown
PARIS(config-if)#exit
PARIS(config-if)#interface loopback 0
PARIS(config-if)#ip address 192.168.0.2 255.255.255.0
PARIS(config-if)#exit
PARIS(config)#interface fastethernet 0
PARIS(config-if)#ip address 192.168.3.1 255.255.255.0
PARIS(config-if)#no shutdown

PARIS(config-if)#exit
PARIS(config)#ip host WARSAW 192.168.2.2 192.168.1.1
WARSAW
Router>enable
Router#configure terminal
Router(config)#hostname WARSAW
WARSAW(config)#enable secret class
WARSAW(config)#line console 0
WARSAW(config-line)#password cisco
WARSAW(config-line)#login
WARSAW(config-line)#line vty 0 4
WARSAW(config-line)#password cisco
WARSAW(config-line)#login
WARSAW(config-line)#exit
WARSAW(config)#interface serial 0
WARSAW(config-if)#ip address 192.168.2.2 255.255.255.252
WARSAW(config-if)#no shutdown
WARSAW(config-if)#exit
WARSAW(config)#interface fastethernet 0
WARSAW(config-if)#ip address 192.168.1.1 255.255.255.0
WARSAW(config-if)#no shutdown
WARSAW(config-if)#exit
WARSAW(config)#ip host WARSAW 192.168.2.1 192.168.3.1
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
Paris#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Paris
IP address: 192.168.3.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.3.1
Host connected to router Warsaw
IP address: 192.168.1.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Chapter 3: EIGRP and Troubleshooting Routing Protocols 197

198 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000
or later, check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process that is required to get communication working while using
EIGRP as the routing protocol.
Task 4: View the Router’s Configuration and Interface Information
Step 1. At the privileged EXEC mode prompt, type the following:
Paris#show running-config
Step 2. Using the show ip interface brief command, check the status of each interface.
What is the state of the interfaces on each router?
Paris:
Warsaw:
■ Fast Ethernet 0: Up
■ Serial 0: Up
■ Fast Ethernet 0: Up
■ Serial 0: Up
Step 3. Ping from one of the connected serial interfaces to the other.
Was the ping successful? Yes
Step 4. If the ping was not successful, troubleshoot the router’s configuration until the ping is successful.
Task 5: Configure EIGRP Routing on Router Paris
Step 1. Enable the EIGRP routing process on router Paris and configure the networks it will advertise.
Use EIGRP autonomous system number 101.
Paris(config)#router eigrp 101
Paris(config-router)#network 192.168.3.0
Paris(config-router)#network 192.168.2.0
Paris(config-router)#network 192.168.0.0
Paris(config-router)#end
Step 2. Show the routing table for the Paris router.
Paris#show ip route
Do entries exist in the routing table? No
Why?
EIGRP is not configured on router Warsaw yet.

Task 6: Configure EIGRP Routing on Router Warsaw
Step 1. Enable the EIGRP routing process on router Warsaw and configure the networks it will advertise.
Use EIGRP autonomous system number 101.
Warsaw(config)#router eigrp 101
Warsaw(config-router)#network 192.168.2.0
Warsaw(config-router)#network 192.168.1.0
Warsaw(config-router)#end
Step 2. Show the routing table for the Warsaw router.
Warsaw#show ip route
Task 7: Test Network Connectivity
Ping the Paris host from the Warsaw host. Was it successful? Yes
If not, troubleshoot as necessary.
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.
Curriculum Lab 3-2: Verifying Basic EIGRP Configuration
(3.2.3)
Figure 3-5 Topology for Lab 3-2
Chapter 3: EIGRP and Troubleshooting Routing Protocols 199
Straight-Through Cable
Rollover (Console) Cable
Router 1 Router 2
Crossover Cable
Serial Cable

200 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 3-3 Lab Equipment Configuration: Part I
Router Designation Router Name Routing Protocol Network Statements
Router 1 Paris EIGRP 192.168.3.0
192.168.2.0
Router 2 Warsaw EIGRP 192.168.1.0
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
Table 3-4 Lab Equipment Configuration: Part II
192.168.2.0
Router IP Host Fast Ethernet 0 Interface Serial 0 Address/ Loopback 0
Designation Table Entry Address/ Type Subnet Mask Address/
Subnet Mask Serial 0 Subnet Mask
Router 1 Warsaw 192.168.3.1/24 DCE 192.168.2.1/30 192.168.0.2/24
Router 2 Paris 192.168.1.1/24 DTE 192.168.2.2/30 No address
The “IP Host Table Entry” column contents indicate the names of the other routers in the IP host table.
Objectives
■ Set up an IP addressing scheme for the network.
■ Configure and verify EIGRP routing.
Background/Preparation
Cable a network that is similar to the one in Figure 3-5. You can use any router that meets the interface
requirements in Figure 3-5 (that is, 800, 1600, 1700, 2500, and 2600 routers or a combination). Refer to
the information in Appendix A to correctly specify the interface identifiers based on the equipment in your
lab. The 1721 series routers produced the configuration output in this lab. Another router might produce
slightly different output. You should execute the following steps on each router unless you are specifically
instructed otherwise. Start a HyperTerminal session.
Implement the procedure documented in Appendix C on all routers before you continue with this lab.
Task 1: Configure the Routers
On the routers, enter global configuration mode and configure the hostname as shown in Tables 3-3 and 3-4.
Then, configure the console, virtual terminal, and enable passwords. Next, configure the interfaces according
to Tables 3-3 and 3-4. Finally, configure the IP hostnames. If you have problems configuring the router
basics, refer to Lab 1-2, “Review of Basic Router Configuration with RIP.”
Note: Do not configure the routing protocol until you are specifically told to.
PARIS
Router>enable
Router#configure terminal
Router(config)#hostname PARIS
PARIS(config)#enable secret class

PARIS(config)#line console 0
PARIS(config-line)#password cisco
PARIS(config-line)#login
PARIS(config-line)#line vty 0 4
PARIS(config-line)#password cisco
PARIS(config-line)#login
PARIS(config-line)#exit
PARIS(config)#interface serial 0
PARIS(config-if)#ip address 192.168.2.1 255.255.255.252
PARIS(config-if)#clock rate 64000
PARIS(config-if)#no shutdown
PARIS(config-if)#exit
PARIS(config-if)#interface loopback 0
PARIS(config-if)#ip address 192.168.0.2 255.255.255.0
PARIS(config-if)#exit
PARIS(config)#interface fastethernet 0
PARIS(config-if)#ip address 192.168.3.1 255.255.255.0
PARIS(config-if)#no shutdown
PARIS(config-if)#exit
PARIS(config)#ip host WARSAW 192.168.2.2 192.168.1.1
WARSAW
Router>enable
Router#configure terminal
Router(config)#hostname WARSAW
WARSAW(config)#enable secret class
WARSAW(config)#line console 0
WARSAW(config-line)#password cisco
WARSAW(config-line)#login
WARSAW(config-line)#line vty 0 4
WARSAW(config-line)#password cisco
WARSAW(config-line)#login
WARSAW(config-line)#exit
WARSAW(config)#interface serial 0
WARSAW(config-if)#ip address 192.168.2.2 255.255.255.252
WARSAW(config-if)#no shutdown
WARSAW(config-if)#exit
WARSAW(config)#interface fastethernet 0
WARSAW(config-if)#ip address 192.168.1.1 255.255.255.0
WARSAW(config-if)#no shutdown
WARSAW(config-if)#exit
WARSAW(config)#ip host PARIS 192.168.2.1 192.168.3.1
Chapter 3: EIGRP and Troubleshooting Routing Protocols 201

202 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 2: Save the Configuration Information from Privileged EXEC
Command Mode
PARIS#copy running-config startup-config
Destination filename [startup-config]? [Enter]
Task 3: Configure the Hosts
Step 1. Configure the hosts with the proper IP address, subnet mask, and default gateway.
Host connected to router Paris
IP address: 192.168.3.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.3.1
Host connected to router Warsaw
IP address: 192.168.1.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.1.1
Step 2. Each workstation should be able to ping the attached router. Troubleshoot as necessary. Hint:
Remember to assign a specific IP address and default gateway to the workstation. If you are
running Windows 98, check using Start > Run > winipcfg. If you are running Windows 2000
or later, check using ipconfig in a DOS window.
Step 3. At this point, the workstations will not be able to communicate with each other. The following
tasks demonstrate the process that is required to get communication working while using
EIGRP as the routing protocol.
Task 4: View the Router’s Configuration and Interface Information
Step 1. At the privileged EXEC mode prompt, type show running-config.
Step 2. Using the show ip interface brief command, check the status of each interface.
Step 3. What is the state of the interfaces on each router?
Paris:
■ Fast Ethernet 0: Up
■ Serial 0: Up
Warsaw:
■ Fast Ethernet 0: Up
■ Serial 0: Up
Step 4. Ping from one of the connected serial interfaces to the other.
Step 5. Was the ping successful? Yes
Step 6. If the ping was not successful, troubleshoot the router’s configuration until the ping is successful.

Task 5: Configure EIGRP Routing on Router Paris
Step 1. Enable the EIGRP routing process on router Paris and configure the networks it will advertise.
Use EIGRP autonomous system number 101.
Paris(config)#router eigrp 101
Paris(config-router)#network 192.168.3.0
Paris(config-router)#network 192.168.2.0
Paris(config-router)#network 192.168.0.0
Paris(config-router)#end
Step 2. Show the routing table for the Paris router.
Paris#show ip route
Do entries exist in the routing table? No
Why?
EIGRP is not configured on Warsaw.
Task 6: Configure EIGRP Routing on Router Warsaw
Step 1. Enable the EIGRP routing process on router Warsaw and configure the networks it will advertise.
Use EIGRP autonomous system number 101.
Warsaw(config)#router eigrp 101
Warsaw(config-router)#network 192.168.2.0
Warsaw(config-router)#network 192.168.1.0
Warsaw(config-router)#end
Step 2. Show the routing table for the Warsaw router.
Warsaw#show ip route
Do EIGRP entries exist in the routing table now? Yes
What is the address type in the EIGRP 192.168.2.0 route? C – Directly Connected
What does the D mean in the first column of the routing table? The route was learned via
EIGRP.
Task 7: Show EIGRP Neighbors
From the Paris router, show any neighbors that are connected by using the show ip eigrp neighbors command
at the privileged EXEC mode prompt.
Are neighbors shown? Yes
Task 8: Test Network Connectivity
Ping the Paris host from the Warsaw host. Was it successful? Yes
If not, troubleshoot as necessary.
Chapter 3: EIGRP and Troubleshooting Routing Protocols 203

204 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 9: View the Topology Table
Step 1. To view the topology table, issue the show ip eigrp topology all-links command.
How many routes are in passive mode? 3
Step 2. To view more specific information about a topology table entry, use an IP address with this
command:
Paris#show ip eigrp topology 192.168.1.0
Based on the output of this command, does it tell what external protocol originated this route to
192.168.2.0? Yes
Does it tell which router originated the route? Yes
Step 3. Use show commands to view key EIGRP statistics. On the Paris router, issue the show ip eigrp
traffic command.
How many hello packets has the Paris router received? Answers will vary.
How many has it sent? Answers will vary.
After you complete the previous steps, log off (by typing exit) and turn the router off. Then, remove and
store the cables and adapter.
Comprehensive Lab 3-3: Comprehensive EIGRP
Configuration
Figure 3-6 EIGRP Configuration
172.16.64.0/20
172.16.80.0/20
172.16.96.0/20
172.16.112.0/20
Lo1
Lo2
Lo3
Lo4
10.0.0.8/30
RTC
T1
S0/0
172.16.0.0/18
Fa0/0
RTA
EIGRP
100
S0/1
DCE
T1
10.0.0.0/30
S0/0
DCE S0/1
S0/1
128kbps
10.0.0.4/30 S0/0
DCE
RTB
Lo1
Lo2
Lo3
Lo4
172.16.128.0/19
172.16.160.0/19
172.16.192.0/19
172.16.224.0/19

Table 3-5 Addressing Table for Lab 3-3
Device Interface IP Address Subnet Mask
RTA S0/1 10.0.0.1 255.255.255.252
S0/0 10.0.0.10 255.255.255.252
Fa0/0 172.16.0.1 255.255.192.0
RTB S0/1 10.0.0.2 255.255.255.252
S0/0 10.0.0.5 255.255.255.252
Lo1 172.16.128.1 255.255.255.224
Lo2 172.16.160.1 255.255.255.224
Lo3 172.16.192.1 255.255.255.224
Lo4 172.16.224.1 255.255.255.224
RTC S0/1 10.0.0.6 255.255.255.252
Objectives
S0/0 10.0.0.9 255.255.255.252
Lo1 172.16.64.1 255.255.255.240
Lo2 172.16.80.1 255.255.255.240
Lo3 172.16.96.1 255.255.255.240
Lo4 172.16.112.1 255.255.255.240
■ Configure EIGRP routing.
■ Configure bandwidth and turn off automatic summarization.
■ Configure manual summarization.
Equipment
The topology shown in Figure 3-6 is using 2600 series routers. This lab can be done with any combination
of 1700, 2500, and 2600 series routers. Connectivity to an ISP is simulated with a Loopback interface on
RTA.
NetLab Compatibility Notes
This lab is fully compatible with a standard NetLab three router pod.
Task 1: Cable the Topology and Basic Configurations
Step 1. Cable the topology as shown. If DCE/DTE connections and interfaces are different from those
shown in Figure 3-6 and the table, then relabel the figure to match your connections.
Step 2. Configure the routers with basic router configurations, including:
■ Hostnames and host tables
■ Enable secret password and MOTD banner
■ Line configurations
Chapter 3: EIGRP and Troubleshooting Routing Protocols 205
■ IOS-specific commands (e.g. ip subnet-zero with IOS versions prior to 12)

206 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 3. The following is a basic configuration for RTA:
Router(config)#hostname RTA
RTA(config)#ip subnet-zero
RTA(config)#no ip domain-lookup
RTA(config)#ip host RTC 10.0.0.9 10.0.0.6
RTA(config)#ip host RTB 10.0.0.2 10.0.0.5
RTA(config)#banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
RTA(config)#line con 0
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#ine aux 0
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#line vty 0 4
RTA(config-line)#exec-timeout 30 0
RTA(config-line)#password cisco
RTA(config-line)#logging synchronous
RTA(config-line)#login
RTA(config-line)#end
RTA#copy run start
Instructor Note: This basic configuration can be used on all three routers with changes to the hostname and the host
table. At this level in their studies, your students should be able to do this with little or no help from you.
Task 2: Configure Interfaces and EIGRP Routing
Step 1. Use Table 3-5 and the topology shown in Figure 3-6 to configure each router with the correct
interface addresses. The interface configuration for RTA is as follows:
RTA(config)#interface FastEthernet0/0
RTA(config-if)#description Link to RTA LAN
RTA(config-if)#ip address 172.16.0.1 255.255.192.0
RTA(config-if)#no shutdown
RTA(config-if)#interface Serial0/0
RTA(config-if)#description Link to RTC
RTA(config-if)#ip address 10.0.0.10 255.255.255.252
RTA(config-if)#clockrate 64000
RTA(config-if)#no shutdown
RTA(config-if)#interface Serial0/1
RTA(config-if)#description Link to RTB
RTA(config-if)#ip address 10.0.0.1 255.255.255.252
RTA(config-if)#clockrate 64000
RTA(config-if)#no shutdown

RTB
RTC
RTB(config)#interface Loopback1
RTB(config-if)#ip address 172.16.128.1 255.255.224.0
RTB(config-if)#interface Loopback2
RTB(config-if)#ip address 172.16.160.1 255.255.224.0
RTB(config-if)#interface Loopback3
RTB(config-if)#ip address 172.16.192.1 255.255.224.0
RTB(config-if)#interface Loopback4
RTB(config-if)#ip address 172.16.224.1 255.255.224.0
RTB(config-if)#interface Serial0/0
RTB(config-if)#description Link to RTC
RTB(config-if)#ip address 10.0.0.5 255.255.255.252
RTB(config-if)#clockrate 64000
RTB(config-if)#no shutdown
RTB(config-if)#interface Serial0/1
RTB(config-if)#description Link to RTA
RTB(config-if)#ip address 10.0.0.2 255.255.255.252
RTB(config-if)#no shutdown
RTC(config)#interface Loopback1
RTC(config-if)#ip address 172.16.64.1 255.255.240.0
RTC(config-if)#interface Loopback2
RTC(config-if)#ip address 172.16.80.1 255.255.240.0
RTC(config-if)#interface Loopback3
RTC(config-if)#ip address 172.16.96.1 255.255.240.0
RTC(config-if)#interface Loopback4
RTC(config-if)#ip address 172.16.112.1 255.255.240.0
RTC(config-if)#interface Serial0/0
RTC(config-if)#description Link to RTA
RTC(config-if)#ip address 10.0.0.9 255.255.255.252
RTC(config-if)#no shutdown
RTC(config-if)#interface Serial0/1
RTC(config-if)#description Link to RTB
RTC(config-if)#ip address 10.0.0.6 255.255.255.252
RTC(config-if)#no shutdown
Step 2. Configure each router with EIGRP routing. The configuration for RTA follows. All routers
have the same basic EIGRP configuration.
RTA(config)#router eigrp 100
RTA(config-router)#network 10.0.0.0
RTA(config-router)#network 172.16.0.0
Task 3: Configure Bandwidth and Automatic Summarization
Step 1. According to the topology shown in Figure 3-6, RTB and RTC are connected with a 128-kbps
link. Enter the commands on both routers necessary to adjust the default bandwidth to match
the actual speed.
RTB(config)#interface Serial0/0
RTC(config-if)#bandwidth 128
RTC(config)#interface Serial0/1
RTC(config-if)#bandwidth 128
Chapter 3: EIGRP and Troubleshooting Routing Protocols 207

208 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 2. Display the routing table on RTA.
RTA#show ip route
(output omitted)
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.16.0.0/16 is a summary, 00:23:16, Null0
C 172.16.0.0/18 is directly connected, FastEthernet0/0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:23:20, Null0
C 10.0.0.0/30 is directly connected, Serial0/1
Step 3. Notice that RTA does not have routes to the simulated LANs on RTB and RTC. Enter the command
to disable automatic summarization on all three routers.
Each router should have the no auto-summary command configured within the
EIGRP routing process.
Task 4: Configure Manual Summarization
Step 1. Display the routing table on RTA.
RTA#show ip route
(output omitted)
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 9 subnets, 3 masks
D 172.16.160.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.128.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.224.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
D 172.16.192.0/19 [90/2297856] via 10.0.0.2, 00:00:16, Serial0/1
C 172.16.0.0/18 is directly connected, FastEthernet0/0
D 172.16.112.0/20 [90/2297856] via 10.0.0.9, 00:00:29, Serial0/0
D 172.16.96.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
D 172.16.80.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
D 172.16.64.0/20 [90/2297856] via 10.0.0.9, 00:00:30, Serial0/0
10.0.0.0/30 is subnetted, 3 subnets
C 10.0.0.8 is directly connected, Serial0/0
C 10.0.0.0 is directly connected, Serial0/1
D 10.0.0.4 [90/21024000] via 10.0.0.9, 00:00:30, Serial0/0
[90/21024000] via 10.0.0.2, 00:00:30, Serial0/1
Step 2. Notice that RTA has 12 routes. Some of these routes can be summarized to reduce the size of
the routing table.
The simulated LANs on RTB share the same bit pattern for the first 21 bits of the network prefix
172.16.128.0.
The simulated LANS on RTC share the same bit pattern for the first 18 bits of the network prefix
172.16.64.0.
What command would you configure on both serial interfaces for RTB?
RTB(config-if)#ip summary-address eigrp 100 172.16.128.0 255.255.128.0

What command would you configure on both serial interfaces for RTC?
RTC(config-if)#ip summary-address eigrp 100 172.16.64.0 255.255.192.0
Step 3. Display the routing table for RTA. You should have only six routes.
RTA#show ip route
(output omitted)
Gateway of last resort is not set
172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
D 172.16.128.0/17 [90/2297856] via 10.0.0.2, 01:36:05, Serial0/1
C 172.16.0.0/18 is directly connected, FastEthernet0/0
D 172.16.64.0/18 [90/2297856] via 10.0.0.9, 01:38:11, Serial0/0
10.0.0.0/30 is subnetted, 3 subnets
C 10.0.0.8 is directly connected, Serial0/0
C 10.0.0.0 is directly connected, Serial0/1
D 10.0.0.4 [90/21024000] via 10.0.0.9, 01:36:05, Serial0/0
[90/21024000] via 10.0.0.2, 01:36:05, Serial0/1
Challenge Lab 3-4: EIGRP Design and Configuration
Figure 3-7 EIGRP Design and Configuration
Public Web Server
209.165.202.129/32
Address Space
10.0.0.0/17
Lo0
209.165.201.0/30
ISP
S0/0
DCE
Chapter 3: EIGRP and Troubleshooting Routing Protocols 209
S0/0
Lo0
Lo1
Lo2
Lo3
HQ
S0/1
DCE
10.0.64.0 / 20
10.0.80.0 / 20
10.0.96.0 / 20
10.0.112.0 / 20
Lo0
Lo1
Lo2
Lo3
WAN
S0/1
Remote
10.0.0.4 / 30
10.0.32.0 / 21
10.0.40.0 / 21
10.0.48.0 / 21
10.0.56.0 / 21

210 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 3-6 Addressing Table for Lab 3-4
Device Interface IP Address Subnet Mask
ISP Lo0 209.165.202.129 255.255.255.255
S0/0 209.165.201.1 255.255.255.252
HQ S0/0 209.165.201.2 255.255.255.252
S0/1 10.0.0.5 255.255.255.252
Lo0 10.0.64.1 255.255.240.0
Lo1 10.0.80.1 255.255.240.0
Lo2 10.0.96.1 255.255.240.0
Lo3 10.0.112.1 255.255.240.0
REMOTE S0/1 10.0.0.6 255.255.255.252
Objectives
Lo0 10.0.32.1 255.255.248.0
Lo1 10.0.40.1 255.255.248.0
Lo2 10.0.48.1 255.255.248.0
Lo3 10.0.56.1 255.255.248.0
■ Design a VLSM addressing scheme.
■ Configure routers with basic configurations using your addressing scheme.
■ Configure dynamic, static, and default routing.
■ Configure manual summarization.
■ Verify connectivity and troubleshoot problems.
Equipment
The topology shown in Figure 3-7 uses 2600 series routers. This lab can be done with any combination of
1700, 2500, and 2600 series routers.
NetLab Compatibility Notes
This lab can be completed on a standard NetLab three router pod.
Task 1: Design the Addressing Scheme
You are given the address space, 10.0.0.0/17. The four loopback interfaces on HQ and four loopback interfaces
on REMOTE are used to simulate different parts of a global network. Complete the following steps
to design your addressing scheme.
Step 1. For HQ, begin with the 10.0.64.0 address as the subnet for loopback 0. What subnet mask
would you use to provide enough space for 4000 users while maximizing the number of subnets?
255.255.240.0 or /20

Step 2. Starting with 10.0.64.0, contiguously assign the next three subnets, all supporting 4000 hosts.
List all four subnets here:
10.0.64.0/20
10.0.80.0/20
10.0.96.0/20
10.0.112.0/20
Step 3. For REMOTE, begin with the 10.0.32.0 address as the subnet for loopback 0. What subnet
mask would you use to provide enough space for 2000 users while maximizing the number of
subnets?
255.255.248.0 or /21
Step 4. Starting with 10.0.32.0, contiguously assign the next three subnets, all supporting 2000 hosts.
List all four subnets here:
10.0.32.0/21
10.0.40.0/21
10.0.48.0/21
10.0.56.0/21
Step 5. Now pick a WAN subnet for the link shared by HQ and REMOTE. List the subnet you
assigned here:
The answer can be any subnet /30 from the 10.0.0.0/21 address space.
Step 6. Label the topology in Figure 3-7 with the networks and finish filling in the IP address table
with your chosen addressing scheme. Use the first available IP address in each subnet as the
interface address. For the WAN subnet, assign HQ the first address.
Task 2: Cable the Topology and Basic Configuration
Step 1. Choose three routers and cable them according to the topology. You do not need any LAN
interfaces or switches for this lab. (If using NetLab, choose a three router pod.)
Step 2. Configure the routers with basic configurations including interface addresses.
Task 3: Configure EIGRP Routing and Default Routing
Step 1. Configure both HQ and REMOTE to use EIGRP as the routing protocol. Enter the simulated
LAN subnets and the WAN link between HQ and REMOTE. Do not advertise the
209.165.201.0/30 network. Make sure you disable automatic summarization.
Step 2. Configure ISP with a static route pointing to the 10.0.0.0/17 Address Space.
Step 3. Configure HQ with a default route pointing to ISP.
Step 4. Configure HQ to advertise the default route to REMOTE with the redistribute static command
within the EIGRP routing process.
HQ(config-router)#redistribute static
Step 5. Verify HQ and REMOTE routing tables:
Chapter 3: EIGRP and Troubleshooting Routing Protocols 211
■ HQ should have six directly connected routes, four EIGRP routes, and one static route.
■ REMOTE should have five directly connected routes, four EIGRP routes, and one EIGRP
external route.

212 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
■ Verify that REMOTE can ping the Simulated Web Server at 209.165.202.129.
REMOTE#ping web
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 209.165.202.129, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 56/56/56 ms
Task 4: Manual Summarization
Because the simulated LANs on both HQ and REMOTE were assigned contiguously, you can summarize
the routing updates to reduce the size of the routing tables. What command will summarize the simulated
LANs on HQ?
HQ(config)#interface serial 0/1
HQ(config-if)#ip summary-address eigrp 100 10.0.64.0 255.255.192.0
What command will summarize the simulated LANs on REMOTE?
REMOTE(config)#interface serial 0/1
REMOTE(config-if)#ip summary-address eigrp 100 10.0.32.0 255.255.224.0
Task 5: Verification and Documentation
Step 1. Capture the following verifications to a text file called verify.txt:
■ Ping output from REMOTE pinging the Simulated Web Server.
■ Capture show ip route on all three routers: ISP, HQ, and REMOTE.
■ Capture show ip eigrp neighbor and show ip eigrp topology on HQ and REMOTE.
Step 2. Capture the running configurations on all three routers to separate text files. Use the hostname
of the router to name each text file.
Step 3. Clean up the verify.txt, HQ.txt, REMOTE.txt, and ISP.txt files. Add appropriate notes to assist
in your studies.
Final configurations and show command output:
HQ hostname HQ
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host REMOTE 10.0.0.6
ip host WEB 209.165.202.129
ip host ISP 209.165.201.1
!
interface Loopback0
!
ip address 10.0.64.1 255.255.240.0
interface Loopback1

!
ip address 10.0.80.1 255.255.240.0
interface Loopback2
!
ip address 10.0.96.1 255.255.240.0
interface Loopback3
!
ip address 10.0.112.1 255.255.240.0
interface Serial0/0
!
description Link to ISP
ip address 209.165.201.2 255.255.255.252
clockrate 64000
no shutdown
interface Serial0/1
!
description Link to REMOTE
ip address 10.0.0.5 255.255.255.252
ip summary-address eigrp 100 10.0.64.0 255.255.192.0
clockrate 64000
no shutdown
router eigrp 100
!
redistribute static
network 10.0.0.0
no auto-summary
eigrp log-neighbor-changes
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0/0
!
banner motd &
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
Chapter 3: EIGRP and Troubleshooting Routing Protocols 213

214 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
HQ#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0/0
10.0.0.0/8 is variably subnetted, 7 subnets, 4 masks
C 10.0.0.4/30 is directly connected, Serial0/1
D 10.0.32.0/19 [90/2297856] via 10.0.0.6, 00:04:47, Serial0/1
D 10.0.64.0/18 is a summary, 00:05:16, Null0
C 10.0.64.0/20 is directly connected, Loopback0
C 10.0.80.0/20 is directly connected, Loopback1
C 10.0.96.0/20 is directly connected, Loopback2
C 10.0.112.0/20 is directly connected, Loopback3
S* 0.0.0.0/0 is directly connected, Serial0/0
HQ#show ip eigrp neighbors
IP-EIGRP neighbors for process 100
H Address Interface Hold Uptime SRTT RTO Q Seq Type
(sec) (ms) Cnt Num
0 10.0.0.6 Se0/1 12 00:05:42 384 2304 0 9
HQ#show ip eigrp topology
IP-EIGRP Topology Table for AS(100)/ID(10.0.112.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 0.0.0.0/0, 1 successors, FD is 2169856
via Rstatic (2169856/0)
P 10.0.0.4/30, 1 successors, FD is 2169856
via Connected, Serial0/1
P 10.0.32.0/19, 1 successors, FD is 2297856

via 10.0.0.6 (2297856/128256), Serial0/1
P 10.0.64.0/18, 1 successors, FD is 128256
via Summary (128256/0), Null0
P 10.0.64.0/20, 1 successors, FD is 128256
via Connected, Loopback0
P 10.0.80.0/20, 1 successors, FD is 128256
via Connected, Loopback1
P 10.0.96.0/20, 1 successors, FD is 128256
via Connected, Loopback2
P 10.0.112.0/20, 1 successors, FD is 128256
REMOTE
hostname REMOTE
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
via Connected, Loopback3
ip host WEB 209.165.202.129
ip host ISP 209.165.201.1
ip host HQ 10.0.0.5
!
interface Loopback0
!
ip address 10.0.32.1 255.255.248.0
interface Loopback1
!
ip address 10.0.40.1 255.255.248.0
interface Loopback2
!
ip address 10.0.48.1 255.255.248.0
interface Loopback3
!
ip address 10.0.56.1 255.255.248.0
interface Serial0/1
!
description Link to HQ
ip address 10.0.0.6 255.255.255.252
ip summary-address eigrp 100 10.0.32.0 255.255.224.0
no shutdown
router eigrp 100
!
network 10.0.0.0
no auto-summary
eigrp log-neighbor-changes
ip classless
!
Chapter 3: EIGRP and Troubleshooting Routing Protocols 215

216 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
banner motd &
***********************************
!!!AUTHORIZES ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
REMOTE#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 10.0.0.5 to network 0.0.0.0
10.0.0.0/8 is variably subnetted, 7 subnets, 4 masks
C 10.0.0.4/30 is directly connected, Serial0/1
C 10.0.40.0/21 is directly connected, Loopback1
D 10.0.32.0/19 is a summary, 00:05:06, Null0
C 10.0.32.0/21 is directly connected, Loopback0
C 10.0.56.0/21 is directly connected, Loopback3
C 10.0.48.0/21 is directly connected, Loopback2
D 10.0.64.0/18 [90/2297856] via 10.0.0.5, 00:04:58, Serial0/1
D*EX 0.0.0.0/0 [170/2681856] via 10.0.0.5, 00:04:58, Serial0/1
REMOTE#show ip eigrp neighbors
IP-EIGRP neighbors for process 100

H Address Interface Hold Uptime SRTT RTO Q Seq Type
(sec) (ms) Cnt Num
0 10.0.0.5 Se0/1 14 00:05:19 24 200 0 11
REMOTE#show ip eigrp topology
IP-EIGRP Topology Table for AS(100)/ID(10.0.56.1)
Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
r - reply Status, s - sia Status
P 0.0.0.0/0, 1 successors, FD is 2681856
via 10.0.0.5 (2681856/2169856), Serial0/1
P 10.0.0.4/30, 1 successors, FD is 2169856
via Connected, Serial0/1
P 10.0.40.0/21, 1 successors, FD is 128256
via Connected, Loopback1
P 10.0.32.0/19, 1 successors, FD is 128256
via Summary (128256/0), Null0
P 10.0.32.0/21, 1 successors, FD is 128256
via Connected, Loopback0
P 10.0.56.0/21, 1 successors, FD is 128256
via Connected, Loopback3
P 10.0.48.0/21, 1 successors, FD is 128256
via Connected, Loopback2
P 10.0.64.0/18, 1 successors, FD is 2297856
ISP hostname ISP
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
via 10.0.0.5 (2297856/128256), Serial0/1
ip host HQ 209.165.201.2
!
interface Loopback0
!
description Simulated Public Web Server
ip address 209.165.202.129 255.255.255.255
interface Serial0/0
!
description Link to HQ
ip address 209.165.201.1 255.255.255.252
no shutdown
ip classless
ip route 10.0.0.0 255.255.128.0 Serial0/0
!
Chapter 3: EIGRP and Troubleshooting Routing Protocols 217

218 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
banner motd &
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
&
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
ISP#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0/0
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
10.0.0.0/17 is subnetted, 1 subnets
S 10.0.0.0 is directly connected, Serial0/0

CHAPTER 4
Switching Concepts
The Study Guide portion of this chapter uses a combination of matching, fill in the blank, open-ended
question, journal entry, and unique custom exercises to test your knowledge on the theory of switching
and switch operation.
There are no Lab Exercises for this chapter.

220 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
Introduction to Ethernet/802.3 LANs
LAN design continues to evolve. Network designers until very recently used hubs and bridges to build networks.
Now switches and routers are the key components in LAN design, and the capabilities and performance
of these devices continue to improve.
As a CCNA candidate, you should have a firm grasp of the concepts involved in the evolution of
Ethernet/802.3, the most commonly deployed LAN architecture. This section offers some exercises to help
you master these concepts.

Vocabulary Exercise: Matching
Definition
a. Ethernet’s collision resolution methodology
b. the fading of a data signal as it travels
through the media
c. reading the entire frame to check for errors
before sending on to the destination
d. filters traffic at Layer 3; segments broadcast
domains
e. Layer 2 device that provides network access
to hosts
f. Layer 2 error-checking mechanism
g. capable of simultaneous transmission and
reception
h. basic unit of time in which one bit can be
sent
i. multiport repeater or LAN concentrator
j. sending a frame out all ports except for the
port it was received on
k. frames are stored in queues that are linked to
specific incoming ports`
l. temporary, dedicated path between two hosts
created by the switch
m. sending out frames as soon as the destination
MAC address is read
n. deposits all frames into a common memory
buffer
o. address contained within the frame header
for Ethernet encapsulations
p. sending a frame out a port based on the unicast
MAC address
q. filters traffic based on Layer 2 addressing; no
longer used in today’s networks
r. forwarding frames after the first 64 bytes are
read
s. delay inherent in sending data from the
source to the destination
t. area of a LAN where frames from two different
sources can run into each other
u. can either send or receive, but not both at the
same time
v. filters traffic at Layer 2; capable of microsegmentation
Chapter 4: Switching Concepts 221
Match the definition on the left with a term on the right. This exercise is not necessarily a one-to-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
Term
t collision domains
i hub
o MAC
q bridge
v switch
l virtual circuit
d router
a carrier sense multiple access collision detect
(CSMA/CD)
u half duplex
g full duplex
e network interface card (NIC)
s latency
h bit time (slot time)
b attenuation
f cyclic redundancy check (CRC)
c store and forward
j flooding
p filtering
k port-based memory buffering
n shared memory buffering
f frame check sequence (FCS)
m cut-through
r fragment-free

222 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
A hub is a Layer 1 device and is sometimes referred to as a LAN or Ethernet concentrator or a multiport
repeater.
Ethernet is fundamentally a shared or broadcast technology through which all users on a given LAN segment
compete for the same available bandwidth. If two or more devices try to transmit at the same time, a
collision occurs.
Bridges and switches operate at the data link layer of the Open System Interconnection (OSI) model.
These Layer 2 devices make forwarding decisions based on MAC addresses contained within the headers
of transmitted data frames.
Switches create a virtual circuit between two connected devices that want to communicate, which is a dedicated
communication path established between the two devices.
The implementation of a switch on the network is called microsegmentation, which creates a collision-free
environment for each device connected to the switch.
The disadvantage of Layer 2 devices is that they forward broadcast frames to all connected devices on the
network.
Routers operate at the network layer of the OSI model and will not forward broadcast frames unless
specifically programmed to do so. Therefore, routers reduce the size of both the collision domains and the
broadcast domains in a network.
CSMA/CD is Ethernet’s access control method. Originally Ethernet was a half-duplex technology, which
allows hosts to either transmit or receive at one time, but not both.
Full-duplex Ethernet significantly improves network performance without the expense of installing new
media and offers 100 percent of the bandwidth in both directions because it is a collision-free environment.
Frames sent by the two connected end nodes cannot collide, because the end nodes use two separate
circuits in the Category 3, 5, 5e, or 6 cable.
Nodes that are attached to hubs that share their connection to a switch port must operate in half-duplex
mode, because the end stations must be able to detect collisions.
Latency, or delay, is the time a frame or a packet takes to travel from the source station to the final destination.
The networking device that adds the most latency is a router.
A 64-byte frame is the smallest frame that allows CSMA/CD to operate properly, and a 1518-byte frame is
the largest.
The distance that a LAN can cover is limited due to attenuation, which means that the signal weakens as it
travels through the network.

CSMA/CD Process Flow Chart Exercise
Draw a flow chart of the CSMA/CD process. Your flow chart should have a minimum of six steps, but can
have more.
Figure 4-1 CSMA/CD Process Flow Chart
Calculate
Back-Off Algorithm
Send Out
Jam Signal
Simple Solution
1. Host wants to transmit
2. Is carrier sensed?
3. Assemble frame
4. Start transmitting
5. Is a collision detected?
6. Keep transmitting
7. Is the transmission done?
8. Transmission completed
9. Broadcast jam signal
10. Attempts = Attempts + 1
11. Attempts > Too many?
12. Too many collisions; abort
transmission
13. Algorithm calculates backoff
14. Wait for t microseconds
Listen to Wire
(Carrier Sense)
Transmit if Free and
Continue to Listen
Collision
Detected?
Finish
Transmission
Complex Solution
1
2
3
4
5
6
7
8
No
No
Yes
Yes
Yes
No
Chapter 4: Switching Concepts 223
9
10
11
12
Yes
No
13
14

224 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Concept Questions
In your own words, describe the function of a router.
Routers examine inbound packets for Layer 3 data, choose the best path to the destination network, and
send the packet out the correct outbound port.
In your own words, explain how CSMA/CD works in half-duplex Ethernet LANs.
Each host checks the network to see whether data is being transmitted before it transmits additional data
(carrier sense). If the network is already in use, the transmission is delayed. Despite transmission deferral,
two or more hosts could transmit at the same time (multiple access). This results in a collision. When a
collision occurs, the host that detects the collision first sends out a jam signal to the other hosts (collision
detection). When a jam signal is received, each host stops data transmission, and then waits for a random
period of time to retransmit the data. The back-off algorithm generates this random delay. The first host
whose time expires can restart the process to transmit data.
Journal Entry
In your own words, describe the various forms of latency. Draw a topology with several networking
devices between two communicating computers as part of your explanation.
Figure 4-2 Your Topology Illustrating Latency
Switches add
some latency
The forms of latency are as follows:
Latency placing the
frame on the wire
Intermediate device latency with
routers adding the most delay
The cloud will
also add latency
Propagation delay as the
frame travels down the wire
Hubs add very
little latency
■ First, there is the time it takes the source NIC to place voltage pulses on the wire and the time it takes
the destination NIC to interpret those pulses. This is sometimes called NIC delay, typically around 1
microsecond for a 10BASE-T NIC.
■ Second, there is the actual propagation delay as the signal takes time to travel through the cable.
Typically, this is about 0.556 microseconds per 100 m for Cat 5 UTP. Longer cable and slower nominal
velocity of propagation (NVP) result in more propagation delay.
■ Third, latency is added based on network devices that are in the path between two computers. These
are either Layer 1, Layer 2, or Layer 3 devices. The more layers a device processes, the more latency
it adds.

Introduction to LAN Switching
In the past, repeaters were used in most Ethernet networks. Because Ethernet is a broadcast topology,
adding repeaters enlarged the domain in which collisions can occur causing a reduction in the bandwidth
available for data transfer. Bridges were soon introduced to create multiple collision domains. Bridges
evolved into switches capable of microsegmenting a LAN, effectively creating a collision-free environment.
Many modern switches are capable of performing varied and complex tasks in the network. For example,
some switches are capable of performing both Layer 2 and Layer 3 functions. The exercises in this section
focus on how a switch or router makes a decision to forward data on its way to the intended destination.
This section provides an introduction to network segmentation and describes the basics of switch operation.
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
Networks can be divided into smaller units by a bridge or a switch. These smaller units are called segments.
Each unit is its own collision domain.
Bridges and switches are Layer 2 devices that forward data frames based on the MAC address. Bridges
read the source MAC address of the data packets to discover the devices that are on each segment. The
source MAC address is used to populate the MAC address table.
Bridges and switches provide segmentation within a single network or subnetwork. Routers provide connectivity
between networks and subnetworks. Routers do not forward broadcasts, whereas switches and
bridges do forward broadcast frames.
When a switch or bridge is first initialized, the MAC address table is empty. With an empty MAC address
table, the switch or bridge must forward each frame to all connected ports other than the one on which the
frame arrived. Sending a frame out all connected ports except the incoming port is called flooding the
frame. Once a switch or a bridge has learned the topology, it can stop frames from propagating onto segments
where the destination does not exist. This process is called filtering.
Building the MAC Address Table Exercise
Assume that the bridge in Figure 4-3 was just installed and powered on. The MAC address table is empty.
Answer the following questions and complete the table as the bridge would build it.
Figure 4-3 Building the MAC Address Table
A
0260.8c01.1111
0260.8c01.2222
E0
E1
Chapter 4: Switching Concepts 225
C
0260.8c01.3333
B D
0260.8c01.4444

226 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Port MAC Address
E0 0260.8c01.1111
E0 0260.8c01.2222
E1 0260.8c01.4444
E1 0260.8c01.3333
1. Host A sends a unicast frame to Host B. What entry, if any, will the bridge enter in its MAC address
table?
The bridge will enter the source MAC address for Host A and the interface that Host A is attached to.
What will the bridge do with the frame?
Because the bridge does not know where Host B is, the bridge will forward the frame to the segment
out E1.
2. Host B responds to Host A with a unicast frame. What entry, if any, will the bridge enter in its MAC
address table?
The bridge will enter the source MAC address for Host B and the interface that Host B is attached to.
What will the bridge do with the frame?
The bridge will drop the frame because the destination host, Host A, is on the same segment as Host
B. Host A has already received the frame.
3. Host D attempts to log in to Server C. What entry, if any, will the bridge enter in its MAC address
table?
The bridge will enter the source MAC address for Host D and the interface that Host D is attached to.
What will the bridge do with the frame?
Because the bridge does not know where Server C is, the bridge will forward the frame to the segment
out E0.
4. Server C responds to the login attempt by Host D. What entry, if any, will the bridge enter in its MAC
address table?
The bridge will enter the source MAC address for Server C and the interface that Server C is attached
to.
What will the bridge do with the frame?
The bridge will drop the frame because the destination host, Host D, is on the same segment as Server
C. Server C has already received the frame.
5. Server C sends out a broadcast frame announcing its services to all potential clients. What entry, if
any, will the bridge enter in its MAC address table?
The bridge will refresh the timestamp on the entry for Server C.
What will the bridge do with the frame?
The bridge will forward the frame out E0 because the destination is a broadcast. Bridges must forward
broadcasts.

Concept Questions
Explain the difference between bridges and switches.
Bridges are store and forward devices and make the switching decision in software. Switches can process
frames faster by using some form of cut-through switching and make the switching decision in hardware.
Switches have less latency than bridges.
Explain why routers cause more latency than do switches, bridges, or hubs.
Routers are Layer 3 devices. Therefore, routers must process data at Layer 3. First, the router deencapsulates
the frame and reads the MAC address. If the MAC address is the router’s MAC or a broadcast, the
router then calculates the CRC to determine if the frame is corrupted. If the frame is not addressed to the
router, is not broadcast, or has errors, it is dropped. Otherwise, the router opens the packet header to examine
the destination IP address, makes a routing decision, and forwards the packet to the outbound interface.
This extra layer of processing causes more latency than a switch causes.
Explain the difference between Layer 2 and Layer 3 switching.
The difference between Layer 2 and Layer 3 switching is the type of information inside the frame that is
used to determine the correct output interface. Layer 2 switching is based on MAC address information.
Layer 3 switching is based on network layer addresses, or IP addresses. The features and functionality of
Layer 3 switches and routers have numerous similarities. The only major difference between the packet
switching operation of a router and a Layer 3 switch is the physical implementation. In general-purpose
routers, packet switching takes place in software, using microprocessor-based engines, whereas a Layer 3
switch performs packet forwarding using application specific integrated circuit (ASIC) hardware.
Journal Entry
Explain how a Layer 2 switch can operate in three different switching modes. Include in your explanation
how much of the frame each method reads, what kind of error checking is performed by the method, and
what the method’s latency is. Include a diagram of a frame illustrating each method.
Fast forward has the lowest latency with no error checking. It reads the destination MAC address and
begins forwarding the frame before the entire frame has been received. Fragment-free switching catches
most errors because it checks up to the first 64 bytes in the Data field. Most errors are the result of collisions
and have sizes less than the 64 byte minimum. Latency is fixed, but slightly higher than fast forward.
However, the improved error detection is usually worth the minor increase in latency. Store and forward
has the highest latency because it stores the entire frame and checks its CRC to determine if there is an
error. Latency is also variable on a frame-by-frame basis because frame size varies.
Note: Students may also mention adaptive cut-through, which is a combination of both fast forward and store and forward.
Initially, the switch operates in fast forward mode. If too many errors are detected beyond a configurable threshold,
then the switch automatically moves to store and forward.
Figure 4-4 Solution Diagram
Chapter 4: Switching Concepts 227
7 Bytes 1 Byte 6 Bytes 6 Bytes 2 Bytes Max 1500 Bytes 4 Bytes
Preamble SFD
Dest.
Address
Source
Address
Length Data FCS
Fast Forward
Fragment-Free
Store-and-Forward

228 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Switch Operation
The exercises in this section reinforce your knowledge of collision and broadcast domains. In addition,
you revisit the concept of picking the correct cable when connecting devices.
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
Even though the LAN switch reduces the size of collision domains, all hosts connected to the switch are
still in the same broadcast domain.
Communication in a network occurs in three ways. The most common way of communication is by
unicast transmissions, in which one transmitter tries to reach one receiver.
Another way to communicate is known as a multicast transmission, in which one transmitter tries to reach
only a subset, or a group, of the entire segment.
The final way to communicate is as a broadcast, in which one transmitter tries to reach all the receivers in
the network.
When a device wants to send out a Layer 2 broadcast, the destination MAC address in the frame is set to
all 1s. A broadcast MAC address is FF:FF:FF:FF:FF:FF in hexadecimal. By setting the destination to this
value, all the devices will accept and process the broadcasted frame.
Routers are used to segment both collision and broadcast domains.
Collision and Broadcast Domains Exercises
Using Figure 4-5, circle all the collision domains with a solid line and all the broadcast domains with a
dashed line.
Figure 4-5 Collision and Broadcast Domains: Topology 1
Broadcast Domain
Collision Domain
Using Figure 4-6, circle all the collision domains with a solid line and all the broadcast domains with a
dashed line.

Figure 4-6 Collision and Broadcast Domains: Topology 2
Using Figure 4-7, circle all the collision domains with a solid line and all the broadcast domains with a
dashed line.
Figure 4-7 Collision and Broadcast Domains: Topology 3
Chapter 4: Switching Concepts 229
Broadcast Domain
Collision Domain
Broadcast Domain
Collision Domain

230 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Choose the Correct Cable Exercise
In the blank provided, indicate with an S for straight-through and C for cross which type of cable would
be used to connect the two devices.
S Hub to workstation or server
C Switch to switch
C Hub to hub
C Router to PC
S Switch to router
C Workstation to workstation
S Switch to workstation or server
C Switch to hub
C Router to router

Lab Exercises
There are no Lab Exercises for this chapter.
Chapter 4: Switching Concepts 231

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CHAPTER 5
LAN Design and Switches
The Study Guide portion of this chapter uses a combination of matching, fill in the blank, open-ended
question, and identification exercises to test your knowledge on the theory of LAN design and the threelayer
hierarchical model.
There are no Lab Exercises for this chapter.

234 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
LAN Design
A network design needs to be functional, scalable, adaptable, and manageable. Designing a network can be
a challenge because it involves much more than just connecting users. A network requires many features in
order to be reliable and available based on the needs of the organization. Understanding the basic design
process and structure of networks will help you to ensure that you are meeting the needs of the network
users.
Vocabulary Exercise: Matching
Match the definition on the left with a term on the right. This exercise is not necessarily a one-to-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
Definition
a. area of a LAN where frames from two different
sources can run into each other
b. switching between ports of different bandwidth
c. local and remote user access
d. cabling that runs between wiring closets
e. responsible for fast switching, redundancy,
and remote access
f. cabling that runs from workstations to the
wiring closet
g. primary wiring closet where POP is located
h. all ports on the switch have the same bandwidth
i. responsible for policy-based connectivity
j. secondary wiring closet
k. used to connect cable runs from user to the
Layer 2 LAN switch ports
l. used to interconnect the various IDFs to the
central MDF
Term
c access layer
i distribution layer
e core layer
g main distribution facility (MDF)
j intermediate distribution facility (IDF)
a collision domain
k horizontal cross-connect (HCC)
l vertical cross-connect (VCC)
b asymmetric switching
h symmetric switching
d backbone or vertical cabling

Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
Chapter 5: LAN Design and Switches 235
The first step in designing a LAN is to establish and document the goals of the design.
Most LANs are designed to meet four major requirements:
■ Functionality, which enables users to meet their job requirements with speed and reliability
■ Scalability, which means that the network should be designed with future growth in mind
■ Adaptability, which means that the network design will easily incorporate new technologies
■ Manageability, which facilitates network monitoring
Servers can be categorized into two distinct classes:
■ Enterprise servers support all the users on the network by offering services such as e-mail, DNS, and
corporate intranet access.
■ Workgroup servers support a specific set of users, offering services such as word processing and file
sharing specific to that group’s needs.
Enterprise servers should be placed in the MDF, and workgroup servers should be placed in the IDF closest
to the users who need it.
One of the most important components to consider when designing a network is the cables/cabling/cable
plant because the physical layer is the cause of most network problems.
Fiber-optic cable should be used in the backbone and risers in all cable designs. Category 5e or Category 6
UTP cable should be used in the horizontal runs. The cable upgrade should take priority over any other
necessary changes.
The TIA/EIA-568-A standard specifies that every device connected to the network should be linked to a
central location with horizontal cabling. In a simple star topology, this central location is the MDF (acronym)
and includes one or more HCCs used to connect the Layer 1 horizontal cabling coming into the wiring
closet from work areas to the Layer 2 LAN switch inside the wiring closet.
In larger network environments, multiple wiring closets are often needed. These extra or secondary wiring
closets are referred to as IDFs.
A VCC in each wiring closet is used to interconnect the various IDFs to the central MDF. The type of
backbone or vertical cabling used is usually fiber-optic because the cable lengths are typically longer than
the 100-meter limit for Category 5e UTP cable.
Complete Figure 5-1 by filling in all the missing text labeling the components of this multibuilding
campus LAN.

236 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 5-1 Extended Star Topology in a Multibuilding Campus
Devices at Layer 2 determine the size of the collision domains, which can negatively affect the performance
of a network. Switches are capable of microsegmentation, which effectively eliminates collisions
because only one host is attached to a switch port.
A router is a Layer 3 device and is one of the most intelligent devices in the network topology. Layer 3
devices allow communication between segments based on Layer 3 addresses.
A router does not forward broadcasts, such as Address Resolution Protocol (ARP) requests. Therefore,
routers segment broadcast domains.
VLAN implementation combines Layer 2 switching and Layer 3 routing technologies to limit both collision
domains and broadcast domains. To communicate between two VLANs, you must use a router.
Concept Questions
List at least four issues that should be addressed in LAN design if you are going to maximize bandwidth
and performance.
■ The function and placement of servers
■ Collision domain issues
■ Segmentation issues
Telecommunications
Outlet/Wall Plate
5 m
Work Area
Station Cable
■ Broadcast domain issues
90 m
Horizontal
Cable Category
5e UTP
■ Port speed on switches and NICs
MDF
■ CPU processors on workstations and servers
HCC
HCC
IDF
HCC
Instructor Note: Your students may list some additional issues that may affect bandwidth. Evaluate each on its
merit. Does it need to be addressed when designing the LAN? If so, give the student credit. Make sure the students are
focusing on LAN issues. Some issues they list may actually be related to the WAN side. For example, “increasing the
bandwidth with the service provider” would not maximize LAN bandwidth and performance.
Uplink
Downlink 100 m
Uplink Port
VCC
Vertical Cable
Multiple Fiber-Optic
Runs for Expansion
VCC
WAN

List and briefly explain the four steps of an effective LAN design methodology.
Step 1. Gather requirements and expectations. This step involves a process of asking questions of key
people and the users within the organization. The goal of this step is to determine what availability
is required.
Step 2. Analyze requirements and data. This is the process of determining what is required to satisfy
the needs of the users and also keeping an eye toward future needs.
Step 3. Design the Layer 1, 2, and 3 LAN structure, or topology. Based on the needs analysis done in
Steps 1 and 2, determine how the cable plant needs to change and choose or upgrade existing
equipment.
Step 4. Document the logical and physical network implementation. This is the most important step.
For troubleshooting purposes as well as future expansion considerations, the importance of
documentation cannot be overstated.
List three purposes of Layer 2 devices.
■ Switch frames based on destination MAC addresses
■ Error detection
■ Reduce congestion
Why do you want vertical cabling to have a greater data capacity than horizontal cabling?
Vertical cabling, or backbone cabling, carries aggregated traffic from multiple users. Therefore, it needs to
be a larger “pipe.” Otherwise, it will be a bottleneck, slowing down data traveling between IDFs.
What factors need to be considered when choosing whether to use a router or switch at a particular point
in the network?
Determine the problem that needs to be solved. If the problem is related to protocol rather than issues of
contention, then routers are the appropriate solution. Routers solve problems with excessive broadcasts,
protocols that do not scale well, security issues, and network layer addresses.
LAN Switches
Cisco recommends designing your networks based on the three-layer hierarchical model. Each of the LAN
design layers discussed in this chapter requires switches and routers that are best suited for the task at
hand. The features, functions, and technical specifications for each switch or router vary based on the LAN
design layer for which the device is intended. For the best network performance, it is important to understand
the role of each layer and then choose the device that best suits the layer requirements.
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
The hierarchical design model includes the following three layers:
■ The access layer provides users in workgroups access to the network.
■ The distribution layer provides policy-based connectivity.
■ The core layer provides optimal transport between sites.
Chapter 5: LAN Design and Switches 237
The access layer is the entry point for user workstations and servers to the network. In a campus LAN, the
device used at this layer is typically a switch.

238 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
This layer’s functions also include MAC layer filtering, which allows switches to direct frames to only the
port the destination is attached to, and microsegmentation, which creates collision-free connections.
The purpose of the distribution layer is to provide a boundary definition in which packet manipulation can
take place. Networks are segmented into broadcast domains by this layer. Policies can be applied and
access control lists can filter packets. This layer isolates network problems to the workgroups in which
they occur and prevents these problems from affecting the core layer. Switches in this layer operate at
Layer 2 and Layer 3.
The core layer is responsible for fast packet switching across the backbone, whether WANs or LANs, and
providing redundant paths.
Three-Layer Hierarchical Model Exercise
For each of the following figures, indicate whether the scenario is an access layer function, distribution
layer function, or core layer function.
Figure 5-2 Scenario 1
In Figure 5-2, an access control list (denoted by the firewall) is implemented to prevent unnecessary network
traffic on the backbone network. The distribution layer is responsible for the implementation of
access control lists.
Figure 5-3 Scenario 2
In Figure 5-3, a telecommuter is shown connecting to headquarters through a modem connection. The
access layer is responsible for allowing telecommuters to connect to the network.
Figure 5-4 Scenario 3
Headquarters
Backbone Network
New York San Jose
T1
In Figure 5-4, the core layer is responsible for connecting New York and San Jose across a T1 link.

Figure 5-5 Scenario 4
In Figure 5-5, the access layer is using 2900 series switches to connect end users to the network.
Figure 5-6 Scenario 5
In Figure 5-6, the distribution layer is using 6000 series switches for inter-VLAN routing.
Figure 5-7 Scenario 6
In Figure 5-7, the core layer is using multilayer switches for fast switching and no packet manipulation.
Figure 5-8 Scenario 7
2900 Switches
6000 Switches
Multilayer Switches
6000 Switches
Chapter 5: LAN Design and Switches 239

240 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
In Figure 5-8, the distribution layer is using multilayer switches to summarize OSPF routes.
Concept Questions
List three functions of the access layer.
■ Local and remote user access
■ MAC layer filtering
■ Microsegmentation
List five functions of the distribution layer
■ Aggregation of the wiring closet connections
■ Broadcast/multicast domain definition
■ VLAN routing
■ Any media transitions that need to occur
■ Security
List three functions of the core layer
■ Fast switching of packets
■ Redundancy
■ Access to remote sites

Lab Exercises
There are no Lab Exercises for this chapter.
Chapter 5: LAN Design and Switches 241

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CHAPTER 6
Catalyst Switch Configuration
The Study Guide portion of this chapter uses a combination of fill in the blank and unique custom exercises
to test your knowledge of switch configuration.
The Lab Exercises portion of this chapter includes all of the online curriculum labs as well as a challenge
lab to ensure that you have mastered the practical, hands-on skills needed about switch configuration.

244 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
Starting the Switch
The exercises in this section focus on knowledge and skills you need before you begin to configure switches.
You should know how to connect to a switch to configure it. You should also be able to interpret the LEDs.
Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
Before configuring a switch, make sure it is plugged in and that the system LED is green. If the system
LED is amber, the switch failed POST and is not operational. To configure a switch, use a rollover cable to
connect the console port on the back of the switch to a COM port on the back of the computer. If using
HyperTerminal as your terminal emulator, you need to configure the port settings in the Properties dialog
box as follows:
Bit per second: 9600
Data bits: 8
Parity: None
Stop bits: 1
Flow control: None
However, simply clicking the Restore Defaults button enters these settings automatically.
After the switch boots, you are asked the following question:
Would you like to enter the initial configuration dialog? [yes/no]:
Just as with a router, answering yes begins Setup mode, in which you are asked a series of basic configuration
questions. If you accidentally answer yes or want to abort Setup mode, use the key combination
Ctrl-C. You can also enter setup mode from the privileged user prompt by entering the command setup.
Answering no gives you the Switch> prompt, from which you can use the command-line interface (CLI)
to configure the switch.
You will find that many of the basic configurations of a switch are identical to what you have already
learned for a router. This is because both devices use the Cisco Internetwork Operating System (IOS). For
example, to enter privileged mode, type the enable command. The prompt changes to Switch#. To enter
global configuration mode, enter configure terminal. The prompt changes to Switch(config)#. At any point
in your configuration, you can enter the ? key to get help.

Switch LED Interpretation Exercise
The LEDs on a switch provide a wealth of information about the switch. Being able to interpret the meanings
of different LED colors and statuses is important for troubleshooting problems and gives the network
engineer a snapshot of current network performance. Refer to Figure 6-1 and answer the following questions
about a switch’s LED.
Figure 6-1 Four Main LEDs on the Catalyst 2950 Switch
System LED
The system LED is off. What does this indicate?
No power to the switch.
What does an amber system LED indicate?
The system failed POST and is not operational.
RPS LED
What does the acronym RPS stand for?
Redundant power supply.
The RPS LED is off. What does this indicate?
No RPS is attached.
System
LED
Port Mode
LEDs
What does a green RPS LED indicate?
A redundant power supply is attached and operational.
What does a flashing green RPS LED indicate?
An RPS is attached but unavailable.
Redundant Power
Supply LED
Mode Button
Chapter 6: Catalyst Switch Configuration 245
Port Status
LEDs
1x 2x 3x 4x 5x

246 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
What does an amber RPS LED indicate?
An RPS is installed but not operational.
What does a flashing amber RPS LED indicate?
The internal power supply failed and the RPS is providing power.
Port Mode LEDs
The STAT mode is currently selected. What does each of the following indicate?
The port LED is off.
No device is attached.
The port LED is flashing green.
The port is sending/receiving traffic on an active link.
The port LED is amber (three reasons).
The port has just detected a link and is currently running STP, in which case the LED will be amber for
30 seconds, the port has been administratively suspended because of an address violation, or the port has
been suspended by STP because of a loop.
The UTIL mode is currently selected. Briefly explain this mode’s purpose assuming the switch is a 2950-24.
If all the port LEDs are green, the switch is using more than 50 percent of total bandwidth. If the far-right
LED is off, the switch is using more than 25 percent but less than 50 percent of the total bandwidth, and
so on. If only the far-left LED is green, the switch is using less than 0.0488 percent of the total bandwidth.
For the DUPLEX and SPEED modes, what does a green LED indicate?
The port is operating in full duplex and at 100 Mbps, respectively.
For the SPEED mode, what does a flashing green LED indicate?
The port is operating at 1000 Mbps.
Configuring the Switch
The exercises in this section focus on switch configuration.
Learn Basic Switch Commands Exercise
For this exercise, refer to Figure 6-2 to answer the following configuration questions. The router is named
DIST because it is a distribution layer router and the switch is named ALSW because it is an access layer
switch.

Figure 6-2 Basic Switch Configuration Exercise
For a Catalyst 2950 switch, the following default configurations are in place:
IP address: 0.0.0.0
CDP: enabled
100BASE-T port: autonegotiate duplex mode
Spanning tree: enabled
Console password: none
The default hostname is Switch. Record the switch prompt and command to change the hostname to
ALSW.
Switch(config)#hostname ALSW
Record the switch prompt and command to configure class as the encrypted enable password.
ALSW(config)#enable secret class
Record the switch prompt and command to enter console line configuration mode.
ALSW(config)#line console 0
Record the switch prompt and command to configure the password cisco on the console line.
ALSW(config-line)#password cisco
Record the switch prompt and command to require users to log in.
ALSW(config-line)#login
DIST
ALSW
VLAN1 192.168.1.2/24
Fa0 192.168.1.1/24
Chapter 6: Catalyst Switch Configuration 247

248 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
The preceding commands should also be entered on the Telnet lines. A switch has 16 Telnet lines numbered
0 to 15. The command to enter Telnet line configuration mode is line vty 0 15.
A switch should be assigned an IP address so that it can be accessed remotely using Telnet or other
TCP/IP applications. Referring to Figure 6-2, record the switch prompt and commands to enter interface
configuration mode and then to configure ALSW with an IP address. Then record the command to activate
the interface.
ALSW(config)#interface vlan1
ALSW(config-if)#ip address 192.168.1.2 255.255.255.0
ALSW(config-if)#no shutdown
To receive and send IP packets, the management interface needs a default gateway. Record the switch
prompt and command to configure ALSW with a default gateway.
ALSW(config)#ip default-gateway 192.168.1.1
The ports on a switch are defaulted to autonegotiate the speed and duplex. However, it is a good idea to set
these to the correct setting for the attached host, because autonegotiation can produce unpredictable results.
Record the switch prompt and commands to configure a port’s interface to 100 Mbps and full duplex.
Note: The commands must be entered in this order. If you try to enter the duplex command first, you will get the
message: “Duplex can not be set until speed is set to non-auto value.”
ALSW(config-if)#speed 100
ALSW(config-if)#duplex full
To enhance security, you can statically configure a port with the MAC address of the host or hosts attached
to that port. Record the switch prompt and command to statically configure the MAC address
0005.9a3c.7800 on port 6.
ALSW(config)#mac-address-table static 0005.9a3c.7800 vlan 1 interface FastEthernet0/6
Instead of explicitly configuring the MAC address, you can configure a port to dynamically learn MAC
addresses and have them “stick” to the current configuration. When in interface configuration mode for
port 5, you need several commands to enable the following security requirements. Be sure the port is in
access mode and do not forget to enable port security. Set the maximum addresses that the port can learn
to 1 and set the port to shut down if another MAC address is detected.
ALSW(config)#interface fastEthernet 0/5
ALSW(config-if)#switchport mode access
ALSW(config-if)#switchport port-security
ALSW(config-if)#switchport port-security maximum 1
ALSW(config-if)#switchport port-security mac-address sticky
ALSW(config-if)#switchport port-security violation shutdown
Briefly explain what each of the following port security violation keywords enables on the interface:
■ protect—When the port reaches the maximum number of MAC addresses, frames with unknown
source addresses are dropped until you remove at least one secure MAC address.
■ restrict—The port will still forward traffic from unknown sources above the maximum number, but
the switch will send an SNMP trap notification to the network management workstation.
■ shutdown—The port is shut down in a err-disabled state for all traffic, and an SNMP trap notification
is sent to the network management station. You can bring it out of this state by entering the errdisable
recovery cause psecure-violation global configuration command, or you can manually re-enable it by
entering the shutdown and no shutdown interface configuration commands.

Lab Exercises
Command Reference
In the following table, record the command, including the correct switch prompt, that fits the description
for a 2950 Catalyst switch. Fill in any blanks with the appropriate missing information.
Command Description
Chapter 6: Catalyst Switch Configuration 249
Switch#show vlan Displays the current VLAN configuration
Switch#delete flash:vlan.dat Removes the VLAN database from Flash memory
Switch(config)#interface vlan1 Enables the virtual interface for VLAN1, the default
VLAN on the switch
Switch(config)#ip default-gateway 192.168.1.1 Configures a gateway to allow IP packets an exit
Switch(config-if)#duplex full Forces full-duplex operation on an interface
Switch(config-if)#duplex auto Enables auto-duplex configuration
Switch(config-if)#duplex half Forces half-duplex operation on an interface
Switch(config-if)#speed 10 Forces 10-Mbps operation on an interface
Switch(config-if)#speed 100 Forces 100-Mbps operation on an interface
Switch(config-if)#speed auto Enables autospeed configuration
Switch#show mac-address-table Displays the current MAC address forwarding table
Switch#clear mac-address-table dynamic Deletes all learned entries from the current MAC address
forwarding table
Switch(config)#mac-address-table static Sets a static address of aaaa.aaaa.aaaa in the MAC
aaaa.aaaa.aaaa vlan 1 interface fa0/1 address table for Fa0/1
Switch(config-if)#switchport port-security Enables port security on the interface
Switch(config-if)#switchport port-security Sets the maximum number of MAC addresses
maximum 1 that a port can learn to 1
Switch(config-if)#switchport port-security Configures the port to dynamically learn MAC addresses
mac-address sticky and “stick” them to the configuration
Switch(config-if)#switchport port-security Configures the port to be disabled if there is a security
violation shutdown violation
Switch(config-if)#switchport port-security Configures the port to send a SNMP trap if a security
violation restrict violation is detected but does not shut down the port
Switch(config-if)#switchport port-security Configures the port to drop all frames from unknown
violation protect source MAC addresses after the maximum configured
MAC addresses have been learned

250 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 6-1: Verifying Default Switch
Configuration (6.2.1)
Figure 6-3 Topology for Lab 6-1
Objective
Investigate the default configuration of a 2900 series switch.
Background/Preparation
Cable a network that is similar to the one in Figure 6-3. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise. Instructions are also provide for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B, “Erasing and Reloading the Switch,” on all switches
before you continue with this lab.
General Configuration Tips
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable
■ Use the question mark (?) and arrow keys to help to enter commands.
■ Each command mode restricts the set of available commands. If you have difficulty entering a command,
check the prompt and then enter ? for a list of available commands. You might be using the
wrong command mode or the wrong syntax.
■ To disable a feature, enter the keyword no before the command, such as no ip address.
■ Save the configuration changes to NVRAM so that you do not lose the changes if there is a system
reload or power outage.

Table 6-1 shows the switch command modes that you should be familiar with for all labs in this chapter.
Table 6-1 Switch Command Modes
Command Access Switch Prompt Exit
Mode Method Displayed Method
User EXEC Log in. Switch> Use the logout command.
Privileged From user EXEC mode, Switch# To exit to user EXEC mode, use the
EXEC enter the enable command. disable, exit, or logout command.
Global From privileged EXEC Switch (config)# To exit to privileged EXEC mode,
configuration mode, enter the configure use the exit or end command, or
terminal command. press Ctrl-Z.
Interface From global configuration Switch (config-if)# To exit to global configuration
configuration mode, enter the interface mode, use the exit command.
type number command, such
as interface serial 0.
Task 1: Enter Privileged Mode
Step 1. Privileged mode gives access to all the switch commands. Because many of the privileged
mode commands configure operating parameters, privileged mode access should be passwordprotected
to prevent unauthorized use. The privileged mode command set includes those commands
that are contained in user EXEC mode, as well as the configure command through
which access to the remaining command modes is gained.
Switch>enable
Switch#
Step 2. Notice that the prompt changed to reflect privileged EXEC mode.
Task 2: Examine the Current Switch Configuration
Step 1. Examine the current running configuration file:
Switch#show running-config
How many Ethernet and Fast Ethernet interfaces does the switch have?
24 Fast Ethernet ports
What is the range of values shown for the VTY lines? 5 to 15
Step 2. Examine the current contents of NVRAM.
Switch#show startup-config
%% Non-volatile configuration memory is not present
Why does the switch give this response?
Nothing is currently stored in NVRAM due to the erase startup.
Chapter 6: Catalyst Switch Configuration 251

252 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 3. Show the current IP address of the switch.
Switch#show interface VLAN 1
Is an IP address set on the switch? No
What is the MAC address of this virtual switch interface?
0004.c075.1500 (answers will vary)
Is this interface up? No
Step 4. You can show the IP properties of the interface by entering the following command:
Switch#show ip interface VLAN 1
Step 5. The following command provides the switch IP address information for the 1900:
#show ip
Task 3: Get Cisco IOS Software Information
Examine the version information that the switch reports.
Switch#show version
What is the IOS version that the switch is running?
12.1(9)EA1
What is the system image filename?
c2950-i6q4l2-mz.121-9.EA1.bin
What is the base MAC address of this switch?
00:04:C0:75:15:00 (answers will vary)
Is the switch running Enterprise Edition software?
No, it is running the standard image.
Is the switch running Enhanced Image software, indicated by the letters EA in the IOS filename (2950
series)? Yes
Task 4: Examine the Fast Ethernet Interfaces
Examine the default properties of the Fast Ethernet interfaces. As an example, examine the properties of
the fourth interface:
Switch#show interface fastethernet 0/4
1900:
#show interface fastethernet 0/26
Note: This is a trunk port.

or
#show interface ethernet 0/4
Note: This is an access port.
2950:
#show interface fastethernet 0/4
Note: This can be a trunk or access port.
or
#show interface gigabitethernet 0/1
Note: This can be a trunk or access port.
Is the interface up or down? Up
What event would make an interface go up?
Attaching a host to the port would make an interface go up.
What is the MAC address of the interface?
0004.c075.1504 (answers will vary)
What is the speed and duplex setting of the interface?
Auto-duplex, Auto-speed
Task 5: Examine VLAN Information
Examine the default VLAN settings of the switch.
Switch#show vlan
What is the name of VLAN 1? Default
Which ports are in this VLAN? All, 1[nd]24
Is VLAN 1 active? Yes
What type of VLAN is the default VLAN? Ethernet
Task 6: Examine Flash Memory (1900: Skip to Step 8)
Examine the contents of the Flash directory.
Switch#dir flash:
or
Switch#show flash
Chapter 6: Catalyst Switch Configuration 253

254 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Name the files and directories found.
2 -rwx 2490607 Mar 01 1993 00:02:56 c2950-i6q4l2-mz.121-9.EA1.bin
3 -rwx 269 Jan 01 1970 00:01:43 env_vars
6 -rwx 108 Mar 01 1993 00:01:37 info
7 drwx 640 Mar 01 1993 00:03:46 html
18 -rwx 108 Mar 01 1993 00:03:46 info.ver
Task 7: Examine the Startup Configuration File
Step 1. To see the contents of the startup configuration file, enter the show running-config command
in privileged EXEC mode.
Switch#show startup-config
Step 2. The switch responds with the following:
Non-volatile configuration memory is not present
Why does this message appear?
No startup configuration file is present.
Step 3. Copy the current configuration to NVRAM. This step ensures that any changes made will be
available to the switch if there is a reload or if the power goes off.
Switch#copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
[OK]
Switch#
Step 4. Show the contents of NVRAM.
Switch#show startup-config
What is displayed now?
A copy of the running configuration is now saved in NVRAM and will be used the next time
the router is rebooted.
Task 8: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.

Curriculum Lab 6-2: Basic Switch Configuration (6.2.2)
Figure 6-4 Topology for Lab 6-2
Table 6-2 Lab Equipment Configuration
Switch Designation Switch Name Enable Secret Password Enable/VTY/Console Password
Switch 1 ALSwitch class cisco
Objectives
■ Configure a switch with a name and an IP address.
■ Configure passwords to ensure that access to the CLI is secured.
■ Configure switch port speed and duplex properties for an interface.
■ Save the active configuration.
■ View the switch browser interface.
Background/Preparation
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Chapter 6: Catalyst Switch Configuration 255
Crossover Cable
Serial Cable
Cable a network that is similar to the one in Figure 6-4. The 2950 series switch produced the configuration
output used in this lab. Another switch might produce different output. You should execute the following
steps on each switch unless you are specifically instructed otherwise. Instructions are also provided for the
1900 series switch, which initially displays a User Interface Menu. Select the Command Line option from
the menu to perform the steps for this lab.

256 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Enter Privileged Mode
Step 1. Privileged mode gives access to all the switch commands. Because many of the privileged
mode commands configure operating parameters, privileged mode access should be passwordprotected
to prevent unauthorized use. The privileged mode command set includes those commands
that are contained in user EXEC mode, as well as the configure command through
which access to the remaining command modes is gained.
Switch>enable
Switch#
1900:
>enable
#
Step 2. Notice that the prompt changed to reflect privileged EXEC mode.
Task 2: Examine the Current Switch Configuration
Step 1. Examine the current running configuration file.
Switch#show running-config
How many Ethernet or Fast Ethernet interfaces does the switch have? 24
What is the range of values shown for the VTY lines? 5–15
Switch#show running-config
Building configuration...
Current configuration : 1427 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Switch
!
!
ip subnet-zero
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
interface FastEthernet0/1
no ip address
!

interface FastEthernet0/2
no ip address
!
interface FastEthernet0/3
no ip address
!
interface FastEthernet0/4
no ip address
!
interface FastEthernet0/5
no ip address
!
interface FastEthernet0/6
no ip address
!
interface FastEthernet0/7
no ip address
!
interface FastEthernet0/8
no ip address
!
interface FastEthernet0/9
no ip address
!
interface FastEthernet0/10
no ip address
!
interface FastEthernet0/11
no ip address
!
interface FastEthernet0/12
no ip address
!
interface FastEthernet0/13
no ip address
!
interface FastEthernet0/14
no ip address
!
interface FastEthernet0/15
no ip address
!
interface FastEthernet0/16
no ip address
!
interface FastEthernet0/17
no ip address
!
interface FastEthernet0/18
no ip address
!
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258 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface FastEthernet0/19
no ip address
!
interface FastEthernet0/20
no ip address
!
interface FastEthernet0/21
no ip address
!
interface FastEthernet0/22
no ip address
!
interface FastEthernet0/23
no ip address
!
interface FastEthernet0/24
no ip address
!
interface Vlan1
no ip address
no ip route-cache
shutdown
!
ip http server
!
!
line con 0
line vty 5 15
!
end
Switch#
Step 2. Examine the current contents of NVRAM.
Switch#show startup-config
startup-config is not present
Why does the switch give this response?
Nothing is saved into NVRAM.
Task 3: Assign a Name to the Switch
Step 1. Enter enable and then configuration mode. Configuration mode allows the management of the
switch. Enter the name by which this switch will be referred, ALSwitch.
Switch#configure terminal
Enter configuration commands, one per line. End with Ctrl+Z.
Switch(config)#hostname ALSwitch
ALSwitch(config)#exit
Step 2. Notice that the prompt changed to reflect its new name. Type exit or press Ctrl-Z to go back
into privileged mode.

Task 4: Examine the Current Running Configuration
Examine the current configuration to verify that there is no configuration except for the hostname.
ALSwitch#show running-config
Are passwords set on lines? No
What does the configuration show as the hostname of this switch? ALSwitch
ALSwitch#show running-config
Building configuration...
Current configuration : 1427 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname ALSwitch
!
!
ip subnet-zero
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
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260 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface Vlan1
no ip route-cache
shutdown
!
ip http server
!
!
line con 0
line vty 5 15
!
end
ALSwitch#

Task 5: Set the Access Passwords (1900: Skip to Task 6)
Enter config-line mode for the console. Set the password on this line to cisco for login. Configure the VTY
lines 5 to 15 with the password cisco.
ALSwitch#configure terminal
Enter configuration commands, one per line. End with Ctrl-Z.
ALSwitch(config)#line con 0
ALSwitch(config-line)#password cisco
ALSwitch(config-line)#login
ALSwitch(config-line)#line vty 0 15
ALSwitch(config-line)#password cisco
ALSwitch(config-line)#login
ALSwitch(config-line)#exit
Task 6: Set the Command Mode Passwords
Set the enable password to cisco and the enable secret password to class.
ALSwitch(config)#enable password cisco
ALSwitch(config)#enable secret class
1900:
ALSwitch(config)#enable password level 15 cisco
ALSwitch(config)#enable secret class
Which password takes precedence: the enable password or the enable secret password? secret
Task 7: Configure Layer 3 Access to the Switch
Step 1. Set the IP address of the switch to 192.168.1.2 with a subnet mask of 255.255.255.0. Note that
this is done on the internal virtual interface VLAN 1.
ALSwitch(config)#interface VLAN 1
ALSwitch(config-if)#ip address 192.168.1.2 255.255.255.0
ALSwitch(config-if)#exit
1900:
ALSwitch(config)#ip address 192.168.1.2 255.255.255.0
ALSwitch(config)#exit
Step 2. Set the default gateway for the switch and the default management VLAN as 192.168.1.1.
ALSwitch(config)#ip default-gateway 192.168.1.1
ALSwitch(config)#exit
1900:
ALSwitch(config)#ip default-gateway 192.168.1.1
ALSwitch(config)#exit
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262 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Verify the Management LAN Settings (1900: Skip to Step 9)
Step 1. Verify the interface settings on VLAN 1.
ALSwitch#show interface VLAN 1
What is the bandwidth on this interface?
1000000 Kbit
What are the VLAN states? VLAN1 is down, and line protocol is down.
Step 2. Enable the virtual interface using the no shutdown command.
ALSwitch(config)#interface VLAN 1
ALSwitch(config-if)#no shutdown
ALSwitch(config-if)#exit
What is the queuing strategy? FIFO
ALSwitch#show interface vlan 1
Vlan1 is administratively down, line protocol is down
Hardware is CPU Interface, address is 0009.b7f6.61c0 (bia 0009.b7f6.61c0)
Internet address is 192.168.1.2/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:06:12, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 5000 bits/sec, 1 packets/sec
47 packets input, 6606 bytes, 0 no buffer
Received 47 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 33 ignored
664 packets output, 372036 bytes, 0 underruns
0 output errors, 3 interface resets
0 output buffer failures, 0 output buffers swapped out
ALSwitch#
Task 9: Configure Port Speed and Duplex Properties for a Fast
Ethernet Interface
Note: 1900 switch access ports can operate only at 10 Mbps, but duplex can be set to full. If the switch has
10/100-Mbps trunk ports, the speed and duplex can be set for these.
Step 1. Prepare to configure the fastethernet 0/4 interface.
ALSwitch#configure terminal
Step 2. Enter configuration commands, one per line. End with Ctrl-Z.
ALSwitch(config)#interface fastethernet 0/4

Step 3. Set the port speed of interface fastethernet 0/4 to 100 Mbps and to operate in full-duplex mode.
ALSwitch(config-if)#speed 100
ALSwitch(config-if)#duplex full
Step 4. If you know that the devices that are connected to a port must operate at a certain speed and in
duplex mode, you should set the interface to that speed and mode.
Task 10: Verify the Settings on a Fast Ethernet Interface
ALSwitch#show interface fastethernet 0/4
ALSwitch#show interfaces fastEthernet 0/4
FastEthernet0/4 is down, line protocol is down (notconnect)
Hardware is Fast Ethernet, address is 000b.be7f.ed44 (bia 000b.be7f.ed44)
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:05:53, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
1 packets input, 64 bytes, 0 no buffer
Received 0 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
1 packets output, 64 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
ALSwitch#
Task 11: Save the Configuration
Step 1. The basic configuration of the switch has just been completed. Back up the running configuration
file to NVRAM. This ensures that the changes made will not be lost if the system is
rebooted or loses power.
ALSwitch#copy running-config startup-config
Destination filename [startup-config]?[Enter]
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264 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Building configuration...
[OK]
ALSwitch#
Step 2. The configuration is automatically saved to NVRAM within approximately 1 minute of entering
a command. To save the configuration to a TFTP server, enter the following:
ALSwitch#copy nvram tftp://tftp server ip address/destination_filename
Task 12: Examine the Startup Configuration File (1900: Skip to
Task 13)
To see the configuration that is stored in NVRAM, enter show startup-config from privileged EXEC
(enable) mode.
ALSwitch#show startup-config
What is displayed?
Copy of the running-configuration
Are all the changes that were entered recorded in the file? Yes
ALSwitch#show startup-config
Using 1302 out of 32768 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname ALSwitch
!
enable secret 5 $1$dw/7$XS/PsFsTanHdxanztCdBO0
enable password cisco
!
ip subnet-zero
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!

interface FastEthernet0/3
!
interface FastEthernet0/4
!
speed 100
duplex full
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
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266 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface FastEthernet0/24
!
interface Vlan1
!
ip address 192.168.1.2 255.255.255.0
no ip route-cache
shutdown
ip default-gateway 192.168.1.1
ip http server
!
line con 0
password cisco
login
line vty 0 4
password cisco
login
line vty 5 15
!
!
password cisco
login
end
Task 13: Remove the Enable and Enable Secret Passwords
ALSwitch#configure terminal
Enter configuration commands, one per line. End with Ctrl+Z.
ALSwitch(config)#no enable password
ALSwitch(config)#no enable secret
1900:
ALSwitch(config)#no enable password level 15
ALSwitch(config)#no enable secret
Task 14: Access the Switch Web Interface
Step 1. Access to the web interface of the switch may be on by default. If it is not on, issue the following
command:
ALSwitch(config)#ip http server
Step 2. Start your web browser.

Step 3. Type the switch IP address into the Location field (Netscape) or Address field (Internet
Explorer) and press Enter.
Step 4. Because you have not secured access to the switch web interface, you will get a web page from
the switch. You will not be asked to supply a username or password.
Task 15: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.
Curriculum Lab 6-3: Managing the MAC Address Table
(6.2.3)
Figure 6-5 Topology for Lab 6-3
Table 6-3 Lab Equipment Configuration
Switch Switch Name VLAN 1 IP Default Gateway Subnet Mask
Designation Address IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objective
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Create a basic switch configuration and manage the switch MAC table.
Chapter 6: Catalyst Switch Configuration 267
Crossover Cable
Serial Cable

268 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Background/Preparation
Cable a network that is similar to the one in Figure 6-5. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-3. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Hosts that Are Attached to the Switch
Configure the hosts to use the same IP subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch IP address from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Record the Host MAC Addresses
Determine and record the Layer 2 addresses of the PC network interface cards.
If you are running Windows 98, check using Start > Run > winipcfg. Click More info.
If you are running Windows 2000 or higher, check using Start > Run > cmd > ipconfig /all.
PC1: 00-01-02-76-8E-EC
PC4: 00-01-02-76-90-DD
Task 5: Determine the MAC Addresses that the Switch Has
Learned
Determine the MAC addresses that the switch has learned by using the show mac-address-table command
at the privileged EXEC mode prompt.
ALSwitch#show mac-address-table
How many dynamic addresses exist? 2
How many MAC addresses exist? 6
How many addresses have been user defined? None
Do the MAC addresses match the host MAC addresses? Yes

Task 6: Determine the show mac-address-table Options
Step 1. Determine the options that the show mac-address-table command has by using the ? option.
ALSwitch#show mac-address-table ?
How many options are available for the show mac-address-table command? 11
ALSwitch#show mac-address-table ?
address address keyword
aging-time aging-time keyword
count count keyword
dynamic dynamic entry type
interface interface keyword
multicast multicast info for selected wildcard
notification MAC notification parameters and history table
static static entry type
vlan VLAN keyword
| Output modifiers
Step 2. Show the MAC address table for the switch.
How many total MAC addresses exist? 6
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0001.0276.8eec DYNAMIC Fa0/1
1 0001.0276.90dd DYNAMIC Fa0/4
Total Mac Addresses for this criterion: 6
Step 3. Show only the MAC address table addresses that were learned dynamically.
How many exist? 2
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
1 0001.0276.8eec DYNAMIC Fa0/1
1 0001.0276.90dd DYNAMIC Fa0/4
Total Mac Addresses for this criterion: 6
Task 7: Clear the MAC Address Table
Remove the existing MAC addresses by using the clear mac-address-table command from the privileged
EXEC mode prompt.
ALSwitch#clear mac-address-table dynamic
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270 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Verify the Results
Verify that the mac-address-table was cleared.
ALSwitch#show mac-address-table
How many MAC addresses exist now? 4
How many dynamic addresses exist? 0
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
Total Mac Addresses for this criterion: 6
Task 9: Determine the clear mac-address-table Options
Determine the options that are available with the command clear mac-address-table ? at the privileged
EXEC mode prompt.
ALSwitch#clear mac-address-table ?
How many options exist? 2
ALSwitch#clear mac-address-table ?
dynamic dynamic entry type
notification Clear MAC notification Global Counters
In what circumstances would these options be used?
They would be used to remove dynamic MAC address entries or clear MAC notification counters.
Task 10: Examine the MAC Table Again
Step 1. Look at the MAC address table again by using the show mac-address-table command at the
privileged EXEC mode prompt.
ALSwitch#show mac-address-table
How many dynamic addresses exist? 2

Why did this change from the last display?
More than likely, the switch has received some broadcasts since the last time you clear the
table.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0001.0276.8eec DYNAMIC Fa0/1
1 0001.0276.90dd DYNAMIC Fa0/4
Total Mac Addresses for this criterion: 6
Step 2. If the table has not changed yet, ping the switch IP address from the hosts two times each and
repeat step 10.
Task 11: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.
Curriculum Lab 6-4: Configuring Static MAC Addresses
(6.2.4)
Figure 6-6 Topology for Lab 6-4
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Chapter 6: Catalyst Switch Configuration 271
Crossover Cable
Serial Cable

272 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 6-4 Lab Equipment Configuration
Switch Switch Name VLAN 1 IP Default Gateway Subnet Mask
Designation Address IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create a static address entry in the switch MAC table.
■ Remove the created static MAC address entry.
Background/Preparation
Cable a network that is similar to the one in Figure 6-6. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-4. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Hosts Attached to the Switch
Configure the hosts to use the same IP subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch IP address from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Record the Host MAC Addresses
Determine and record the Layer 2 addresses of the PC network interface cards.
If you are running Windows 98, check using Start > Run > winipcfg. Click More info.
If you are running Windows 2000, check using Start > Run > cmd > ipconfig /all.
PC1: 08-00-46-06-FB-B6 (example; answers will vary)
PC4: 00-08-74-4D-8E-E2 (example; answers will vary)

Task 5: Determine the MAC Addresses that the Switch Has
Learned
Determine the MAC addresses that the switch has learned by using the show mac-address-table command
at the privileged EXEC mode prompt.
ALSwitch#show mac-address-table
How many dynamic addresses exist? 2
How many MAC addresses exist? 6
Do the MAC addresses match the host MAC addresses? They should.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 DYNAMIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 6: Determine the mac-address-table Options
Determine the options that the mac-address-table command has by using the ? option.
ALSwitch(config)#mac-address-table ?
How many options are available for the mac-address-table command? 3
ALSwitch(config)#mac-address-table ?
aging-time Set MAC address table entry maximum age
notification Enable/Disable MAC Notification on the switch
static static keyword
There is an option to set a static MAC address in the table. Under what circumstances would you use this
option? To add security to your switch.
Task 7: Set Up a Static MAC Address
Set up a static MAC address on Fast Ethernet interface 0/4. Use the address that was recorded for PC4 in
Task 4. The MAC address 00e0.2917.1884 is used in the example statement only.
ALSwitch(config)#mac-address-table static 00e0.2917.1884 interface fastethernet 0/4 vlan 1
1900:
Chapter 6: Catalyst Switch Configuration 273
ALSwitch(config)#mac-address-table permanent 00e0.2917.1884 ethernet 0/4

274 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Verify the Results
Verify the MAC address table entries.
ALSwitch#show mac-address-table
How many MAC addresses exist now? 5
How many static addresses exist? 5
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/4
Total Mac Addresses for this criterion: 5
Under what circumstances can other static or dynamic learning of addresses occur on switch port 4?
Connecting a hub to that port will enable that to occur.
Task 9: Remove the Static MAC Entry
You might need to reverse the static mac-address-table entry. To do this, enter configuration mode and
reverse the command by putting no in front of the entire old command string. The MAC address
00e0.2917.1884 is used in the example statement only. Use the MAC address that was recorded for the
host on port 0/4.
ALSwitch(config)#no mac-address-table static 00e0.2917.1884 interface
fastethernet 0/4 vlan 1
1900:
ALSwitch(config)#no mac-address-table permanent 00e0.2917.1884
ethernet 0/4

Task 10: Verify the Results
Verify that the static MAC address was cleared.
ALSwitch#show mac-address-table static
ALSwitch#show mac-address-table static
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 DYNAMIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
How many static MAC addresses exist now? 4
Task 11: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.
Curriculum Lab 6-5: Configuring Port Security (6.2.5)
Figure 6-7 Topology for Lab 6-5
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Chapter 6: Catalyst Switch Configuration 275
Crossover Cable
Serial Cable

276 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 6-5 Lab Equipment Configuration
Switch Switch Name VLAN 1 Default Gateway Subnet Mask
Designation IP Address IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create and verify a basic switch configuration.
■ Configure port security on individual Fast Ethernet ports.
Background/Preparation
Cable a network that is similar to the one in Figure 6-7. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-5. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Hosts Attached to the Switch
Step 1. Configure the hosts to use the same IP subnet for addresses, masks, and the default gateway as
the switch.
Step 2. You need a third host for this lab. You must configure this host with the address 192.168.1.7.
The subnet mask is 255.255.255.0 and the default gateway is 192.168.1.1. Do not connect this
PC to the switch yet.
Task 3: Verify Connectivity
To verify that the hosts and switch are configured correctly, ping the switch IP address from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Record the Hosts’ MAC Addresses
Determine and record the Layer 2 addresses of the PC network interface cards.
If you are running Windows 98, check using Start > Run > winipcfg. Click More info.

If you are running Windows 2000, check using Start > Run > cmd > ipconfig /all.
PC1: 08-00-46-06-FB-B6 (example; answers will vary)
PC4: 00-08-74-4D-8E-E2 (example; answers will vary)
Task 5: Determine the MAC Addresses that the Switch Has
Learned
Determine the MAC addresses that the switch has learned by using the show mac-address-table command
at the privileged EXEC mode prompt.
ALSwitch#show mac-address-table
How many dynamic addresses exist? 2
How many MAC addresses exist? 6
Do the MAC addresses match the host MAC addresses? They should.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 DYNAMIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 6: Determine the mac-address-table Options
Determine the options that the mac-address-table command has by using the ? option.
ALSwitch(config)#mac-address-table ?
ALSwitch(config)#mac-address-table ?
aging-time Set MAC address table entry maximum age
notification Enable/Disable MAC Notification on the switch
static static keyword
Task 7: Set Up a Static MAC Address
Set up a static MAC address on Fast Ethernet interface 0/4. Use the address that was recorded for PC4 in
Task 4. The MAC address 00e0.2917.1884 is used in the example statement only.
ALSwitch(config)#mac-address-table static 00e0.2917.1884 interface
fastethernet 0/4 vlan 1
1900:
ALSwitch(config)#mac-address-table permanent 00e0.2917.1884 ethernet
0/4
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278 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Verify the Results
Verify the MAC address table entries.
ALSwitch#show mac-address-table
How many static addresses exist? 5
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 9: List Port Security Options
Step 1. Determine options for setting port security on interface Fast Ethernet 0/4. Enter switchport
port security ? from the interface configuration prompt for Fast Ethernet port 0/4.
ALSwitch(config)#interface fastethernet 0/4
ALSwitch(config-if)#switchport port-security ?
aging Port-security aging commands
mac-address Secure mac address
maximum Max secure addresses
violation Security violation mode
1900:
ALSwitch(config)#interface ethernet 0/4
ALSwitch(config-if)#port secure ?
max-mac-count Maximum number of addresses allowed on the port
Step 2. Allow the switch port fastethernet 0/4 to accept only one device by using the following commands:
ALSwitch(config-if)#switchport mode access
ALSwitch(config-if)#switchport port-security
ALSwitch(config-if)#switchport port-security mac-address sticky
1900:
ALSwitch(config-if)#port secure

Task 10: Verify the Results
Step 1. Verify the MAC address table entries.
ALSwitch#show mac-address-table
How are the address types listed for the two MAC addresses?
The entry for Fa0/1 is DYNAMIC but the entry for Fa0/4 is STATIC.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Step 2. Show port security settings.
ALSwitch#show port-security
ALSwitch#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security Action
(Count) (Count) (Count)
—————————————————————————————————————-
Fa0/4 1 0 0
Shutdown
—————————————————————————————————————-
Total Addresses in System (excluding one mac per port) : 0
Max Addresses limit in System (excluding one mac per port) : 1024
1900:
ALSwitch#show mac-address-table security
Task 11: Show the Running Configuration File
Do some statements directly reflect the security implementation in the listing of the running configuration?
Yes
What do those statements mean?
Port security is enabled.
interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security mac-address sticky
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280 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 12: Limit the Number of Hosts Per Port
Step 1. On interface fastethernet 0/4, set the port security maximum MAC count to 1.
ALSwitch(config)#interface fastethernet 0/4
ALSwitch(config-if)#switchport port-security maximum 1
1900:
ALSwitch(config)#interface Ethernet 0/4
ALSwitch(config-if)#port secure max-mac-count 1
Step 2. Disconnect the PC that is attached to fastethernet 0/4 and connect to that port the PC that has
been given the IP address 192.168.1.7. This PC has not been attached to the switch. To generate
some traffic, you might need to ping the switch address 192.168.1.2.
Record your observations.
Task 13: Configure the Port to Shut Down if a Security Violation
Occurs
Step 1. If a security violation occurs, you should shut down the interface. Make the port security action
shutdown.
2950
ALSwitch(config-if)#switchport port-security violation shutdown
1900:
ALSwitch(config-if)#port security action shutdown
In addition to shutdown, what other violation options are available with port security?
protect, restrict
Step 2. If necessary, ping the switch address 192.168.1.2 from the PC 192.168.1.7 that is now connected
to interface fastethernet 0/4. This ensures that there is traffic from the PC to the switch.
Record your observations.
The ping was successful.
Task 14: Show Port 0/4 Configuration Information
To see the configuration information for Fast Ethernet port 0/4, enter show interface fastethernet 0/4 at
the privileged EXEC mode prompt.
ALSwitch#show interface fastethernet 0/4
1900:
ALSwitch#show interface ethernet 0/4
What is the state of this interface?
Fast Ethernet 0/4 is UP, and line protocol is UP.
ALSwitch#show interface fastethernet 0/4
FastEthernet0/4 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 000a.b772.2b44 (bia

000a.b772.2b44)
MTU 1500 bytes, BW 100000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s
input flow-control is off, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:01, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute ouxtput rate 0 bits/sec, 0 packets/sec
161 packets input, 19257 bytes, 0 no buffer
Received 137 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 5 multicast, 0 pause input
0 input packets with dribble condition detected
349 packets output, 29399 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
Task 15: Reactivate the Port
Step 1. If a security violation occurs and the port is shut down, use the no shutdown command to
reactivate it.
Step 2. Try this a few times, switching between the original port 0/4 host and the new one. Plug in the
original host, enter the no shutdown command on the interface, and ping by using the DOS
window. You have to repeat the ping multiple times or use the ping 192.168.1.2 -n 200 command.
This sets the number of ping packets to 200 instead of 4. Then, switch hosts and try
again.
Task 16: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.
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282 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 6-6: Add, Move, and Change MAC
Addresses (6.2.6)
Figure 6-8 Topology for Lab 6-6
Table 6-6 Lab Equipment Configuration
Switch Switch Name VLAN 1 Default Gateway Subnet Mask
Designation IP Address IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create and verify a basic switch configuration.
■ Move a PC from one switch port to another and add a new PC to the switch.
Background/Preparation
Cable a network that is similar to the one in Figure 6-8. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable
Implement the procedure documented in Appendix B before you continue with this lab.

Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-6. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Hosts Attached to the Switch
Step 1. Configure the hosts to use the same IP subnet for addresses, masks, and the default gateway as
the switch.
Step 2. You need a third host for this lab. You must configure it with the address 192.168.1.7. The subnet
mask is 255.255.255.0 and the default gateway is 192.168.1.1. Do not connect this PC to
the switch yet.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch IP address from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Record the Hosts’ MAC Addresses
Determine and record the Layer 2 addresses of the PC network interface cards.
If you are running Windows 98, check using Start > Run > winipcfg. Click More info.
If you are running Windows 2000, check using Start > Run > cmd > ipconfig /all.
PC1: 08-00-46-06-FB-B6 (example; answers will vary)
PC4: 00-08-74-4D-8E-E2 (example; answers will vary)
Task 5: Determine the MAC Addresses that the Switch Has
Learned
Determine the MAC addresses that the switch has learned by using the show mac-address-table command
at the privileged EXEC mode prompt.
ALSwitch#show mac-address-table
How many dynamic addresses exist? 2
How many MAC addresses exist? 6
Do the MAC addresses match the host MAC addresses? They should.
ALSwitch#show mac-address-table
Mac Address Table
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284 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 DYNAMIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 6: Determine the mac-address-table Options
Determine the options that the mac-address-table command has by using the ? option.
ALSwitch(config)#mac-address-table ?
ALSwitch(config)#mac-address-table ?
aging-time Set MAC address table entry maximum age
notification Enable/Disable MAC Notification on the switch
static static keyword
Task 7: Set Up a Static MAC Address
Set up a static MAC address on Fast Ethernet interface 0/4. Use the address that was recorded for PC4 in
Step 4. The MAC address 00e0.2917.1884 is used in the example statement only.
ALSwitch(config)#mac-address-table static 00e0.2917.1884 interface
fastethernet 0/4 vlan 1
1900:
ALSwitch(config)#mac-address-table permanent 00e0.2917.1884 ethernet
0/4
Task 8: Verify the Results
Verify the MAC address table entries.
ALSwitch#show mac-address-table
How many static addresses exist? 5
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU

All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 9: List Port Security Options
Step 1. Determine options for setting port security on interface Fast Ethernet 0/4. Enter switchport
port security ? from the interface configuration prompt for Fast Ethernet port 0/4.
ALSwitch(config)#interface fastethernet 0/4
ALSwitch(config-if)#port security ?
aging Port-security aging commands
mac-address Secure mac address
maximum Max secure addrs
violation Security Violation Mode
1900:
ALSwitch(config)#interface ethernet 0/4
ALSwitch(config-if)#port secure ?
max-mac-count Maximum number of addresses allowed on the port
Step 2. Allow the switch port Fast Ethernet 0/4 to accept only one device by using the following commands:
ALSwitch(config-if)#switchport mode access
ALSwitch(config-if)#switchport port-security
ALSwitch(config-if)#switchport port-security mac-address sticky
1900:
ALSwitch(config-if)#port secure
Task 10: Verify the Results
Verify the MAC address table entries.
ALSwitch#show mac-address-table
How are the address types listed for the two MAC addresses?
1 static and 1 dynamic
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
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286 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1 0008.744d.8ee2 STATIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 11: Show the Running Configuration File
In the listing of the running configuration, do some statements directly reflect the security implementation?
Yes
What do those statements mean?
Port security is enabled.
interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security mac-address sticky
Task 12: Limit the Number of Hosts Per Port
Step 1. On interface Fast Ethernet 0/4, set the port security maximum MAC count to 1.
ALSwitch(config)#interface fastethernet 0/4
ALSwitch(config-if)#switchport port-security maximum 1
1900:
ALSwitch(config)#interface ethernet 0/4
ALSwitch(config-if)#port secure max-mac-count 1
Step 2. Disconnect the PC that is attached to Fast Ethernet 0/4 and connect to that port the PC that has
been given the IP address 192.168.1.7. This PC has not been attached to the switch. To generate
some traffic, ping the switch address 192.168.1.2 with the -n 50 option. For example, use
ping 192.168.1.2 -n 50, where 50 is the number of pings sent.
Task 13: Move Host
Step 1. Reconnect the PC that had previously been connected to Fast Ethernet 0/4 to Fast Ethernet 0/8.
The PC has been moved to a new location. This could be to another VLAN, but in this
instance, all switch ports are in VLAN 1 and network 192.168.1.0.
Step 2. From this PC on Fast Ethernet 0/8, ping 192.168.1.2 -n 50.
Was this successful? Yes
Why or why not?
No port security is enabled.
Step 3. Show the MAC address table.
ALSwitch#show mac-address-table

Step 4. Record the VLAN 1 MAC addresses that are displayed.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6
Task 14: Clear the MAC Address Table
Step 1. Clear the MAC address table. Doing so unlocks the MAC addresses from security and allows a
new address to be registered.
ALSwitch#clear mac-address-table dynamic
Step 2. From the PC on the Fast Ethernet 0/8, ping 192.168.1.2 -n 50.
Was this successful? Yes
Step 3. If not, troubleshoot as necessary.
Task 15: Change the Security Settings
Step 1. Show the MAC address table.
ALSwitch#show mac-address-table
Step 2. Observe that Fast Ethernet 0/4 is secure but that the security should be applied to the machine
on port 0/8 because that is the machine that was moved form port 0/4. Remove port security
from interface Fast Ethernet 0/4.
ALSwitch(config)#interface fastethernet 0/4
ALSwitch(config-if)#no switchport port-security
ALSwitch(config-if)#no switchport port-security mac-address sticky
ALSwitch(config-if)#no switchport port-security mac-address sticky
0008.744d.8ee2
ALSwitch(config-if)#shutdown
ALSwitch(config-if)#no shutdown
1900:
ALSwitch(config)#interface ethernet 0/4
ALSwitch(config-if)#no port secure
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288 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 3. Apply port security with a max-mac-count of 1 to interface Fast Ethernet 0/8.
ALSwitch(config)#interface fastethernet 0/8
ALSwitch(config-if)#switchport mode access
ALSwitch(config-if)#switchport port-security
ALSwitch(config-if)#switchport port-security mac-address sticky
ALSwitch(config-if)#switchport port-security maximum 1
1900:
ALSwitch(config)#interface ethernet 0/8
ALSwitch(config-if)#port secure max-mac-count 1
Step 4. Clear the MAC address table.
Note: You also could have cleared individual entries.
ALSwitch#clear mac-address-table dynamic
Task 16: Verify the Results
Verify that the MAC address table has been cleared.
ALSwitch#show mac-address-table
Can all PCs still successfully ping each other? Yes
If not, troubleshoot the switch and PCs.
ALSwitch#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 0009.b7f6.61c0 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 0008.744d.8ee2 STATIC Fa0/8
1 00b0.d026.6ab5 DYNAMIC Fa0/4
1 0800.4606.fbb6 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 6

Task 17: Exit the Switch
Step 1. Exit to the switch welcome screen.
Switch#exit
Step 2. Remove and store the cables and adapter.
Curriculum Lab 6-7: Managing Switch Operating System
Files (6.2.7a)
Figure 6-9 Topology for Lab 6-7
Table 6-7 Lab Equipment Configuration
Switch Designation Switch Name VLAN 1 IP Address Default Gateway IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1
The enable secret password is class.
The enable, VTY, and console password is cisco.
The subnet mask is 255.255.255.0.
Objectives
■ Create and verify a basic switch configuration.
■ Back up the switch IOS to a TFTP server and then restore it.
Background/Preparation
Cable a network that is similar to the one in Figure 6-9. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Straight-Through Cable
Rollover (Console) Cable
Chapter 6: Catalyst Switch Configuration 289
Implement the procedure documented in Appendix B before you continue with this lab.
FA0/1
Crossover Cable
Serial Cable

290 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-7. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Host that Is Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
This host will act as the TFTP server in this lab. Be sure to take note of the IP address that is assigned.
Task 3: Verify Connectivity
To verify that the host and switch are configured correctly, ping the switch IP address from the host.
Was the ping successful? Yes
If the answer is no, troubleshoot the host and switch configurations.
Task 4: Start and Configure the Cisco TFTP Server
Step 1. The TFTP server that is indicated in Figure 6-10 might not be the same one that is used in this
classroom. Please check with the instructor for the operating instructions for the TFTP server
that is used in place of the Cisco TFTP server.
Figure 6-10 TFTP Server Startup

Step 2. After the TFTP server is running and shows the proper address configured on the workstation,
proceed to the actual copying of the Cisco IOS Software image file to the switch.
Task 5: Copy the IOS Image to the TFTP Server (1900: Skip to
Step 9)
Step 1. Before you try to copy the files, verify that the TFTP server is running.
What is the IP address of the TFTP server? 192.168.1.10
Step 2. From the console session, enter show flash.
What is the name and length of the IOS image that is stored in Flash memory?
c2950-i6q4l2-mz.121-9.EA1.bin, 2,490,607 bytes (answers will vary)
What attributes can you identify from codes in the IOS filename?
Version 12.1(9)EA1 (answers will vary)
ALSwitch#show flash
Directory of flash:/
2 -rwx 2490607 Mar 1 1993 02:23:28 +00:00 c2950-i6q4l2-mz.121-
9.EA1
a.bin
3 -rwx 269 Jan 1 1970 00:01:45 +00:00 env_vars
4 -rwx 1278 Mar 1 1993 00:10:01 +00:00 config.text
5 -rwx 5 Mar 1 1993 00:10:01 +00:00 private-config.text
6 -rwx 17 Mar 1 1993 02:00:21 +00:00 testfile.txt
7 drwx 2688 Mar 1 1993 02:25:45 +00:00 html
19 -rwx 110 Mar 1 1993 02:21:13 +00:00 info
20 -rwx 110 Mar 1 1993 02:25:48 +00:00 info.ver
2494816 bytes total (580096 bytes free)
Step 3. From the console session in privileged EXEC mode, enter the copy flash tftp command. At the
prompt, enter the IP address of the TFTP server.
ALSwitch#copy flash tftp
Source filename []?c2950-i6q4l2-mz.121-9.EA1.bin
Address or name of remote host []? 192.168.1.10
Destination filename [c2950-i6q4l2-mz.121-9.EA1.bin]?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
2490607 bytes copied in 19.378 secs (94924 bytes/sec)
ALSwitch#
Task 6: Verify the Transfer to the TFTP Server
Chapter 6: Catalyst Switch Configuration 291
Step 1. Verify the transfer by choosing View > Log File to check the TFTP server log file. The output
should look something like the following:
Mon Sep 19 14:10:08 2005: Receiving ‘c2950-i6q4l2-mz.121-9.EA1.bin’ in binary
mode
Mon Sep 19 14:11:14 2005: Successful.

292 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 2. Verify the Flash image size in the TFTP server directory. To locate it, choose View > Options.
This shows the TFTP server root directory. It should be similar to the following, unless the
default directories were changed:
C:\Program Files\Cisco Systems\Cisco TFTP Server
Step 3. Locate this directory by using File Manager and look at the detail listing of the file. The file
length in the show flash command should be the same file size as the file stored on the TFTP
server. If the file sizes are not identical, check with your instructor.
Task 7: Copy the IOS Image from the TFTP Server
Step 1. Now that the IOS image is backed up, the image must be tested and the IOS image must be
restored to the switch. Verify again that the TFTP server is running, is sharing a network with
the switch, and can be reached by pinging the TFTP server IP address.
Record the IP address of the TFTP server. 192.168.1.10
Step 2. Start the actual copying, from the privileged EXEC prompt. Do not interrupt the process!
ALSwitch#copy tftp flash
Address or name of remote host []? 192.168.1.10
Source filename []? c2950-i6q4I2-mz.121-9.EA1.bin
Destination filename [c2950-i6q4I2-mz.121-9.EA1.bin]?[Enter]
%Warning:There is a file already existing with this name
Do you want to over write? [confirm][Enter]
Accessing tftp://192.168.1.10/c2950-i6q4I2-mz.121-9.EA1.bin...
Loading c2950-i6q4I2-mz.121-9.EA1.bin from 192.168.1.10 (via VLAN1):
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 2490607 bytes]
2490607 bytes copied in 80.986 secs (22544 bytes/sec)
ALSwitch#
The switch might prompt you to overwrite Flash. Will the image fit in available Flash? Yes
What is the size of the file that is being loaded? 2490607
What happened on the switch console screen as the file was being downloaded?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Was the verification successful? Yes
Was the whole operation successful? Yes
Task 8: Test the Restored IOS Image
Step 1. To verify that the switch IOS image is correct, cycle the switch power and observe the startup
process to confirm that there were no Flash errors. If there were no errors, then the switch’s
IOS image should have started correctly. Also, to further verify the IOS image in Flash, issue
the show version command, which shows output similar to the following:
System image file is “flash:/c2950-i6q4I2-mz.121-9.EA1.bin”
ALSwitch#show version
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4I2), Version 12.1(9)EA1, RELEASE SOFTWARE

(fc1)
Copyright 1986-2004 by cisco Systems, Inc.
Compiled Mon 19-Apr-04 20:58 by yenanh
Image text-base: 0x80010000, data-base: 0x805A8000
ROM: Bootstrap program is C2950 boot loader
ALSwitch uptime is 1 hour, 19 minutes
System returned to ROM by power-on
System image file is “flash:/c2950-i6q4l2.121-9.EA1.bin”
cisco WS-C2950-24 (RC32300) processor (revision G0) with 20713K bytes of memory.
Processor board ID FHK0651Y0KA
Last reset from system-reset
Running Standard Image
24 FastEthernet/IEEE 802.3 interface(s)
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:0B:BE:7F:ED:40
Motherboard assembly number: 73-5781-11
Power supply part number: 34-0965-01
Motherboard serial number: FOC06500SRB
Power supply serial number: DAB06498VHC
Model revision number: G0
Motherboard revision number: A0
Model number: WS-C2950-24
System serial number: FHK0651Y0KA
Configuration register is 0xF
Step 2. Exit to the switch welcome screen.
Switch#exit
Step 3. Remove and store the cables and adapter.
Task 9: Procedure for 1900 Switch Firmware Upgrade Using TFTP
Step 1. Select option F to go to the Firmware Configuration menu from the Main Menu. An example
of the Firmware Configuration menu follows:
Catalyst 1900 - Firmware Configuration
Chapter 6: Catalyst Switch Configuration 293
——————————- System Information —————————————
FLASH: 1024K bytes
V8.01.00 : Enterprise Edition
Upgrade status:
No upgrade currently in progress.
——————————- Settings ——————————————————
[S] TFTP Server name or IP address 192.168.1.3
[F] Filename for firmware upgrades cat1900.bin
[A] Accept upgrade transfer from other hosts Enabled

294 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
——————————- Actions ——————————————————-
[U] System XMODEM upgrade [D] Download test subsystem
(XMODEM)
[T] System TFTP upgrade [X] Exit to Main Menu
Step 2. Ensure that the switch firmware upgrade file is available on the TFTP server in the default
directory. The file can be copied from another networking device or computer or it can be
downloaded to the server from an appropriate website.
Step 3. Select option S from the Firmware Configuration menu and enter the IP address of the server
where the switch upgrade file is located.
Step 4. Select option F from the Firmware Configuration menu and enter the name of the firmwareupgrade
file.
Step 5. Select T from the Firmware Configuration menu to initiate the upgrade.
Step 6. Verify that the upgrade is in progress by checking the Upgrade Status field of the Firmware
Configuration menu. If the upgrade is in progress, the field reads “in-progress.”
Step 7. When the transfer is complete, the switch resets automatically and executes the newly downloaded
firmware.
Caution: During the transfer of the upgrade file, the switch might not respond to commands for as long as 1 minute.
This is normal and correct. If you interrupt the transfer by turning the switch off and on, the firmware could be corrupted.
Curriculum Lab 6-8: Managing Switch Startup
Configuration Files (6.2.7b)
Figure 6-11 Topology for Lab 6-8
Straight-Through Cable
Rollover (Console) Cable
FA0/1
Crossover Cable
Serial Cable

Table 6-8 Lab Equipment Configuration
Switch Designation Switch Name VLAN 1 IP Address Default Gateway
IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1
The enable secret password is class.
The enable, VTY, and console password is cisco.
The subnet mask is 255.255.255.0.
Objectives
■ Create and verify a basic switch configuration.
■ Back up the switch startup configuration file to a TFTP server and then restore it.
Background/Preparation
Cable a network that is similar to the one in Figure 6-11. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-8. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Host that Is Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
This host will act as the TFTP server in this lab. Be sure to take note of the IP address that is assigned.
Task 3: Verify Connectivity
To verify that the host and switch are correctly configured, ping the switch IP address from the host.
Was the ping successful? Yes
If the answer is no, troubleshoot the host and switch configurations.
Task 4: Start and Configure the Cisco TFTP Server
Chapter 6: Catalyst Switch Configuration 295
Step 1. The TFTP server that is indicated in Figure 6-12 might not be the same one that is used in this
classroom. Please check with the instructor for the operating instructions for the TFTP server
that is used in place of the Cisco TFTP server.

296 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 6-12 TFTP Server Startup
Step 2. After the TFTP server is running and shows the proper address configured on the workstation,
proceed to the copying of the configuration file to the switch.
Task 5: Copy the Startup Configuration File to the TFTP Server
Step 1. Before you try to copy the files, verify that the TFTP server is running.
What is the IP address of the TFTP server? 192.168.1.10
Step 2. From the console session, enter show flash.
For a 2900 switch, use the command dir flash:.
Note: This function is not supported on the 1900 switch.
What is the name and length of the startup configuration image that is stored in Flash?
config.text, 1278 bytes
ALSwitch#show flash
Directory of flash:/
2 -rwx 2490607 Mar 1 1993 02:23:28 +00:00 c2950-i6q4l2-mz.121-
9.EA1
a.bin
3 -rwx 269 Jan 1 1970 00:01:45 +00:00 env_vars
4 -rwx 1278 Mar 1 1993 00:10:01 +00:00 config.text
5 -rwx 5 Mar 1 1993 00:10:01 +00:00 private-config.text
6 -rwx 17 Mar 1 1993 02:00:21 +00:00 testfile.txt
7 drwx 2688 Mar 1 1993 02:25:45 +00:00 html
19 -rwx 110 Mar 1 1993 02:21:13 +00:00 info
20 -rwx 110 Mar 1 1993 02:25:48 +00:00 info.ver
2494816 bytes total (580096 bytes free)

Step 3. From the console session in privileged EXEC mode, enter copy running-config startup-config
to make sure that the running configuration file is saved to the startup configuration file.
Then, enter the copy startup-config tftp command. At the prompt, enter the IP address of the
TFTP server.
ALSwitch#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Building configuration...
[OK]
ALSwitch#copy startup-config tftp
Address or name of remote host []? 192.168.1.10
Destination filename [alswitch-confg]?[Enter]
!!
1278 bytes copied in 1.60 secs (744 bytes/sec)
ALSwitch#
Step 4. For the 1900 switch, use the following to copy the switch configuration file to a TFTP server:
ALSwitch#copy nvram tftp://192.168.1.3/alswitch-config
Configuration upload is successfully completed
Task 6: Verify the Transfer to the TFTP Server
Step 1. Verify the transfer by choosing View > Log File to check the TFTP server log file. The output
should look something like the following:
Mon Sep 19 14:10:08 2005: Receiving ‘alswitch.confg’ file from 192.168.1.2 in
binary mode
Mon Sep 19 14:11:14 2005: Successful.
Step 2. Verify the Flash image size in the TFTP server directory. To locate it, choose View > Options.
This shows the TFTP server root directory. It should be similar to the following, unless the
default directories were changed:
C:\Program Files\Cisco Systems\Cisco TFTP Server
Step 3. Locate this directory by using File Manager and look at the detail listing of the file. The file
length in the show flash command should be the same file size as the file that is stored on the
TFTP server. If the file sizes are not identical, check with your instructor.
Task 7: Restore the Startup Configuration File from the TFTP
Server
Step 1. Erase the switch startup configuration file.
Step 2. Reconfigure the file with just the VLAN 1 IP address of 192.168.1.2 255.255.255.0.
Step 3. Enter the command copy tftp startup-config at the privileged EXEC mode prompt. Do not
interrupt the process!
Switch#copy tftp startup-config
Address or name of remote host []? 192.168.1.10
Source filename []? alswitch-confg
Destination filename [startup-config]?
Accessing tftp://192.168.1.10/alswitch-confg...
Loading alswitch-confg from 192.168.1.10 (via VLAN1): !
Chapter 6: Catalyst Switch Configuration 297

298 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
[OK - 744 bytes]
[OK]
1278 bytes copied in 0.100 secs
Switch#
Was the operation successful? Yes
Step 4. For the 1900 switch, use the following to copy the switch configuration file to a TFTP server:
ALSwitch#copy tftp://192.168.1.10/alswitch-config nvram
TFTP successfully downloaded configuration file
Task 8: Test the Restored Startup Configuration Image (Not
Supported on the 1900)
Step 1. To verify that the switch image is correct, cycle the switch power and observe the switch prompt.
If it has returned to the name that was assigned to it in the original configuration, the restoration
is complete. Enter the command show startup-config to see the restored configuration.
ALSwitch#show startup-config
Using 1278 out of 32768 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname ALSwitch
!
enable secret 5 $1$Oi07$I3c8fVXNd3wvifcRVulG2.
enable password cisco
!
ip subnet-zero
!
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
!
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6

!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface Vlan1
!
ip address 192.168.1.2 255.255.255.0
no ip route-cache
shutdown
ip default-gateway 192.168.1.1
ip http server
!
line con 0
password cisco
login
line vty 0 4
password cisco
login
line vty 5 15
password cisco
Chapter 6: Catalyst Switch Configuration 299

300 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
!
login
end
Step 2. Exit to the switch welcome screen.
Switch#exit
Step 3. Remove and store the cables and adapter.
Curriculum Lab 6-9: Password Recovery Procedure on a
Catalyst 2900 Series Switch (6.2.8)
Figure 6-13 Topology for Lab 6-9
Table 6-9 Lab Equipment Configuration
Switch Designation Switch Name VLAN 1 IP Address Default Gateway IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1
The enable secret password is class.
The enable, VTY, and console password is cisco.
The subnet mask is 255.255.255.0.
Objectives
Straight-Through Cable
Rollover (Console) Cable
■ Create a basic switch configuration and verify it.
■ Change passwords so that the password recovery procedure must be performed.
FA0/1
Crossover Cable
Serial Cable

Background/Preparation
Cable a network that is similar to the one in Figure 6-13. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-9. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Host that Is Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the host and switch are correctly configured, ping the switch IP address from the host.
Was the ping successful? Yes
If the answer is no, troubleshoot the host and switch configurations.
Task 4: Reset the Console Password
Step 1. Have a classmate change the console and VTY passwords on the switch, save the changes to
the startup-config file, and reload the switch.
Step 2. Without knowing the passwords, try to gain access to the switch.
Task 5: Recover Access to the Switch
Step 1. Make sure that a PC is connected to the console port and that a HyperTerminal window is
open.
Step 2. Power off the switch and turn it back on by holding down the Mode button on the front of the
switch at the same time that the switch is powered on. Release the Mode button a few seconds
after the STAT LED is no longer lit.
Step 3. The following should be displayed:
Chapter 6: Catalyst Switch Configuration 301
C2950 Boot Loader (C2950-HBOOT-M) Version 12.1(11r)EA1, RELEASE SOFTWARE (fc1)
Compiled Mon 22-Jul-02 18:57 by antonino
WS-C2950-24 starting...
Base ethernet MAC Address: 00:0a:b7:72:2b:40
Xmodem file system is available.

302 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
The system has been interrupted prior to initializing the Flash file system. The following commands
initialize the Flash file system and finish loading the operating system software:
flash_init
load_helper
boot
Step 4. To initialize the file system and finish loading the operating system:
Type flash_init.
Type load_helper.
Type dir flash: (do not forget to type the : (colon) after the word flash).
Step 5. Type rename flash:config.text flash:config.old to rename the configuration file.
This file contains the password definition.
Task 6: Restart the System
Step 1. Type boot to boot the system.
Step 2. Enter N at the prompt to start the Setup program.
Continue with the configuration dialog? [yes/no] : N
Step 3. Type rename flash:config.old flash:config.text to rename the configuration file with its original
name at the privileged EXEC mode prompt.
Step 4. Copy the configuration file into memory.
Switch#copy flash:config.text system:running-config
Source filename [config.text]?[Enter]
Destination filename [running-config][Enter]
Step 5. The configuration file is now reloaded, so change the old unknown passwords and save the new
configuration.
ALSwitch#configure terminal
ALSwitch(config)#no enable secret
ALSwitch(config)#enable password Cisco
ALSwitch(config)#line console 0
ALSwitch(config-line)#password cisco
ALSwitch(config-line)#exit
ALSwitch(config)#line vty 0 15
ALSwitch(config-line)#password cisco
ALSwitch(config-line)#exit
ALSwitch(config)#exit
ALSwitch#copy running-config startup-config
Destination filename [startup-config]?[Enter]
Building configuration...
[OK]
ALSwitch#
Step 6. Power cycle the switch and verify that the passwords are now functional.
If they are not, repeat the procedure.
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.

Task 7: Procedure for the 1900 and 2800 Switches
Check the boot firmware version number from the Systems Engineering menu. To access the Systems
Engineering menu, follow this procedure:
Step 1. Disconnect the power cord from the rear panel.
Step 2. Press and hold the Mode button on the front panel.
Step 3. Power-cycle the switch.
Step 4. Release the Mode button one or two seconds after the LED above port 1x goes off or when the
diagnostic console is displayed.
Cisco Systems Diagnostic Console
Copyright Cisco Systems, Inc. 1999
All rights reserved.
Ethernet Address: 00-E0-1E-7E-B4-40
————————————————————————-
Press Enter to continue.
Step 5. Press Enter to display the Diagnostic Console [nd] Systems Engineering menu:
Diagnostic Console - Systems Engineering
Operation firmware version: 8.00.00 Status: valid
Boot firmware version: 3.02
[C] Continue with standard system start up
[U] Upgrade operation firmware (XMODEM)
[S] System Debug Interface
Enter Selection:
The bold letters show the Boot firmware version.
Clearing the Password (Firmware Version 1.10 and Later)
Step 1. Power-cycle the switch.
After POST completes, the following prompt displays:
Do you wish to clear the passwords? [Y]es or [N]o:
Note: You have 10 seconds to respond. If you do not respond within that time, the Management Console Logon screen
appears. You cannot change this waiting period.
Step 2. Enter Y to delete the existing password from NVRAM.
Note: If you type N, the existing password remains valid.
Chapter 6: Catalyst Switch Configuration 303
Step 3. Assign a password from the switch management interfaces (management console or CLI).

304 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Viewing the Password (Firmware Versions Between 1.10 and 3.02)
For firmware versions between 1.10 and 3.02, you can view the password you are trying to recover
(instead of clearing it as described in the previous section).
Step 1. Access the diagnostic console:
Press and hold the Mode button.
Power-cycle the switch.
Release the Mode button one or two seconds after the LED above port 1x goes off or the diagnostics
console appears.
You will see the following logon screen:
————————————————————————-
Cisco Systems Diagnostic Console
Copyright Cisco Systems, Inc. 1999
All rights reserved.
Ethernet Address: 00-E0-1E-7E-B4-40
————————————————————————-
Press Enter to continue.
Step 2. Press Enter and select the [S] option on the Diagnostic Console – Systems Engineering menu,
and then select the [V] option on the Diagnostic Console – System Debug Interface menu to
display the management console password.
Step 3. If you want to change the password, select the [M] option on the Console Settings menu.
Password Recovery for Firmware Version 1.09 and Earlier
Note: If the shipping date is before June 1997, gather the information listed in this section and contact the Cisco
Technical Assistance Center (TAC) for password recovery.
Note: This section is also applicable for those Catalyst 2800 switches that do not have the Mode button in their front
panel.
To recover your password, follow these steps:
Step 1. Contact the Cisco TAC for the factory-installed password.
Step 2. Provide the serial number or MAC address of the switch.
The serial number is usually located on the back of the unit. To obtain the MAC address,
remove the cover and read the Ethernet address of the PROM.

Curriculum Lab 6-10: Firmware Upgrade of a Catalyst
2950 Series Switch (6.2.9)
Figure 6-14 Topology for Lab 6-10
Table 6-10 Lab Equipment Configuration
Switch Designation Switch Name VLAN 1 IP Address Default Gateway IP Address
Switch 1 ALSwitch 192.168.1.2 192.168.1.1
The enable secret password is class.
The enable, VTY, and console password is cisco.
The subnet mask is 255.255.255.0.
Objectives
■ Create a basic switch configuration and verify it.
■ Upgrade the IOS and HTML files from a file that the instructor supplies.
Background/Preparation
Cable a network that is similar to the one in Figure 6-14. The 2950 switch produced the configuration output
in this lab. Another switch might produce different output.
Start a HyperTerminal session.
Straight-Through Cable
Rollover (Console) Cable
Chapter 6: Catalyst Switch Configuration 305
Implement the procedure documented in Appendix B before you continue with this lab.
FA0/1
Crossover Cable
Serial Cable

306 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Important Note: This lab requires that a combined IOS image and HTML file c2950-c3h2s-mz.120-5.3.WC.1.tar be
in the default file directory of the TFTP server. The instructor should download this file from the Cisco Connection
online software center. This file is the latest update for the Catalyst 2950. It has the same filename stem as the current
image, but for the purpose of the lab, assume that this is an update. The IOS update release contains new HTML files
to support changes to the web interface.
This lab requires that there be a saved copy of the current configuration file as backup.
Task 1: Configure the Switch
Configure the hostname and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 6-10. If you have problems while performing this configuration, refer to Curriculum
Lab 6-2, “Basic Switch Configuration (6.2.2).”
Task 2: Configure the Host Attached to the Switch
Configure the host to use the same IP subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the host and switch are correctly configured, ping the switch IP address from the host.
Was the ping successful? Yes
If the answer is no, troubleshoot the host and switch configurations.
Task 4: Display the Name of the Running Image File
Step 1. Display the name of the running image file by using the show boot command from the privileged
EXEC mode prompt.
ALSwitch#show boot
BOOT path-list:
Config file: flash:config.text
Enable Break: no
Manual Boot: no
HELPER path-list:
NVRAM/Config file
buffer size: 32768
ALSwitch#
Step 2. If, as shown in the previous step, no software image is defined in the boot path, enter dir flash:
or show flash to display the contents.
ALSwitch#dir flash:
Directory of flash:/
2 -rwx 1674921 Mar 01 1993 01:28:10 c2950-c3h2s-mz.120-5.3.WC.1.bin
3 -rwx 269 Jan 01 1970 00:00:57 env_vars
4 drwx 10240 Mar 01 1993 00:21:13 html
165-rwx 965 Mar 01 1993 00:22:23 config.text
7741440 bytes total (4778496 bytes free)

Task 5: Prepare for the New Image
Step 1. If the switch has enough free memory, as shown in the previous step, rename the existing IOS
image file to the same name with the .old extension. If there is not enough memory, make sure
that a copy of the IOS image exists on the TFTP server.
ALSwitch#rename flash: c2950-c3h2s-mz.120-5.3.WC.1.bin flash:
c2950-c3h2s-mz.120-5.3.WC.1.old
Step 2. Verify that the renaming was successful.
ALSwitch#dir flash:
Directory of flash:/
2 -rwx 1674921 Mar 01 1993 01:28:10 c2950-c3h2s-mz.120-5.3.WC.1.old
3 -rwx 269 Jan 01 1970 00:00:57 env_vars
4 drwx 10240 Mar 01 1993 00:21:13 html
167 -rwx 965 Mar 01 1993 00:22:23 config.text
7741440 bytes total (4778496 bytes free)
ALSwitch#
Step 3. As a precaution, disable access to the switch HTML pages.
ALSwitch(config)#no ip http server
Task 6: Extract the New IOS Image and HTML Files into Flash
Memory
Step 1. Use the tar command as shown:
ALSwitch#tar /x tftp://192.168.1.3//c2950-c3h2s-mz.120-
5.4.WC.1.tar flash:
Note: Depending on the TFTP server that is being used, you might need only one slash (/) after the IP address of the
server.
Step 2. Re-enable access to the switch HTML pages.
ALSwitch(config)#ip http server
Step 3. Remove existing HTML files.
ALSwitch#delete flash:html/*
Task 7: Associate the New Boot File
Enter the boot command with the name of the new image filename at the configuration mode prompt.
ALSwitch(config)#boot system flash:c2950-c3h2s-mz.120-5.4.WC.1.bin
Chapter 6: Catalyst Switch Configuration 307

308 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Restart the Switch
Step 1. Restart the switch by using the reload command to see if the new IOS loaded. Use the show
version command to see the IOS filename.
What is the name of the IOS file that the switch booted from?
flash:c2950-i6q4l2-mz.121-13.EA1.bin
Is this the proper filename? Yes
Step 2. If the IOS filename is now correct remove the backup file from flash memory using the command
delete flash: c2950-c3h2s-mz.120-5.3.WC.1.old from the Privileged EXEC mode
prompt to remove the backup file.
Step 3. Exit to the switch welcome screen.
Switch#exit
Step 4. Remove and store the cables and adapter.
Challenge Lab 6-11: Basic Switch Configuration with Port
Security
Figure 6-15 Basic Switch Configuration with Port Security
Objectives
■ Prepare the switch for a new configuration.
■ Apply basic configurations.
■ Enable and test port security.
Fa0/4 A
ALSW
VLAN1 192.168.1.2/24
B
192.168.1.3/24
192.168.1.4/24

Equipment
The topology shown in Figure 6-15 is using a 2950 Catalyst series switch. You also need two different PCs
to test the port security.
Note: Command output for this lab is based on a 2950 series switch running Cisco IOS version 12.1(13)EA1. The
commands you need to use and the output may differ. If necessary, consult with your instructor for the correct commands.
Alternatively, you can research the commands for your particular switch platform and IOS at Cisco.com. This
would be an excellent way to enhance your Cisco device configuration skills and to simulate a “real-world” situation,
namely, researching the command set for a particular device that is a part of your production network.
NetLab Compatibility Notes
Much of this lab can be completed on a NetLab basic switch pod. However, to test port security, your
NetLab setup must support PCs.
Task 1: Cable the Topology and Clear the Configuration
Step 1. Choose a 2950 switch and attach a workstation to FastEthernet 0/4.
Step 2. Make sure the switch has an empty startup configuration and that the VLAN database has been
deleted. Then, reload the switch. What commands must be used to carry out this instruction?
How do you verify that the VLAN database has been deleted?
Switch#erase startup-config
Switch#delete flash:vlan.dat
Switch#reload
Use the command show flash to verify that the vlan.dat file has been deleted.
Task 2: Configure the Switch
Step 1. Configure the switch with the following basic requirements:
■ Hostname
■ Enable password
■ Banner MOTD
■ Line configurations
■ Other instructor-required global configurations
Step 2. Check your configurations. What command did you use?
show running-config
Step 3. Although there is not a router shown in Figure 6-15, one would eventually be attached.
Configure the management interface, activate it, and configure 192.168.1.1 as the default gateway.
What commands did you use?
ALSW(config)#interface vlan1
ALSW(config-if)#ip address 192.168.1.2 255.255.255.0
ALSW(config-if)#no shutdown
ALSW(config)#ip default-gateway 192.168.1.1
Chapter 6: Catalyst Switch Configuration 309

310 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 4. Configure the two hosts. What configurations did you use?
Host A:
■ IP address: 192.168.1.3
■ Subnet Mask: 255.255.255.0
■ Default Gateway: 192.168.1.1
Host B:
■ IP address: 192.168.1.4
■ Subnet Mask: 255.255.255.0
■ Default Gateway: 192.168.1.1
Step 5. Verify that host A can ping ALSW. If it cannot, troubleshoot.
Task 3: Configure and Test Port Security
Step 1. For FastEthernet 0/4, implement the following port security requirements:
■ Use port security to dynamically learn only one MAC address.
■ Set the port to be disabled if there is a violation.
What commands did you use?
ALSW(config)#interface fastEthernet 0/4
ALSW(config-if)#switchport mode access
ALSW(config-if)#switchport port-security
ALSW(config-if)#switchport port-security maximum 1
ALSW(config-if)#switchport port-security mac-address sticky
ALSW(config-if)#switchport port-security violation shutdown
Step 2. Verify that the MAC address for host A is now part of the configuration for ALSW. What command
did you use?
show run or show run interface fa0/4
ALSW#show run
Building configuration...
(output omitted)
!
interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security mac-address sticky 00b0.d092.8057
!
(output omitted)
ALSW#show run interface fa0/4
!
interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security mac-address sticky 00b0.d092.8057
Is the MAC address for host A “stuck” to the configuration for ALSW? If not, troubleshoot.

Step 3. What commands can you use to verify port security?
show port-security
show port-security address
show port-security interface fa0/4
ALSW#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security Action
(Count) (Count) (Count)
—————————————————————————————————————-
Fa0/4 1 1 0
Shutdown
—————————————————————————————————————-
Total Addresses in System (excluding one mac per port) : 0
Max Addresses limit in System (excluding one mac per port) : 1024
ALSW#show port-security address
Secure Mac Address Table
—————————————————————————————————-
Vlan Mac Address Type Ports Remaining Age
(mins)
—— —————- —— ——- ——————-
1 00b0.d092.8057 SecureSticky Fa0/4 -
—————————————————————————————————-
Total Addresses in System (excluding one mac per port) : 0
Max Addresses limit in System (excluding one mac per port) : 1024
ALSW#show port-security interface fa0/4
Port Security : Enabled
Port Status : Secure-up
Violation Mode : Shutdown
Aging Time : 0 mins
Aging Type : Absolute
SecureStatic Address Aging : Disabled
Maximum MAC Addresses : 1
Total MAC Addresses : 1
Configured MAC Addresses : 0
Sticky MAC Addresses : 1
Last Source Address : 00b0.d092.8057
Security Violation Count : 0
Chapter 6: Catalyst Switch Configuration 311
Step 4. Test port security by removing host A and attaching host B to the FastEthernet 0/4 port. The
port LED should turn from green to OFF. If it does not, send a frame to ALSW by pinging its
VLAN interface from host B. Watch for console messages from the switch. You should see the
following:
00:06:03: %PM-4-ERR_DISABLE: psecure-violation error detected on Fa0/4, putting
Fa0/4 in err-disable state
00:06:03: %PORT_SECURITY-2-PSECURE_VIOLATION: Security violation occurred,
caused by MAC address 00b0.d092.80c3 on port FastEthernet0/4.
00:06:04: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/4,
changed state to down
00:06:05: %LINK-3-UPDOWN: Interface FastEthernet0/4, changed state to down

312 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 5. Assume that host B is the new workstation for FastEthernet 0/4. How would you clear the disabled
status of the port so that the MAC address for host B will be accepted?
ALSW#clear port-security sticky
ALSW(config)#int fa0/4
ALSW(config-if)#shutdown
00:13:14: %LINK-5-CHANGED: Interface FastEthernet0/4, changed state to administratively
down
ALSW(config-if)#no shutdown
00:13:20: %LINK-3-UPDOWN: Interface FastEthernet0/4, changed state to up
00:13:21: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/4,
changed state to up
Step 6. Verify that the MAC address for host B is now part of the configuration for ALSW. What command
did you use?
show run or show run interface fa0/4
ALSW#show run int fa0/4
Building configuration...
Current configuration : 212 bytes
!
interface FastEthernet0/4
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security mac-address sticky 00b0.d092.80c3
spanning-tree portfast

CHAPTER 7
Spanning Tree Protocol
The Study Guide portion of this chapter uses a combination of matching, fill in the blank, open-ended
question, journal entry, and unique custom exercises to test your knowledge on the theory of redundant
topologies and Spanning Tree Protocol (STP).
The Lab Exercises portion of this chapter includes all of the online curriculum labs to ensure that you have
mastered the practical, hands-on skills needed about redundant topologies and STP.

314 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
Redundant Topologies
Redundancy in a network is required to protect against loss of connectivity due to the failure of an individual
component. However, this provision can result in physical topologies with loops. Physical layer loops
can cause serious problems in switched networks. This section includes exercises to reinforce your understanding
of redundant networks and the unique problem of broadcast storms.
Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
Redundancy allows networks to be fault tolerant, which protects against network downtime. Focusing
specifically on networking, list a few things that can cause network downtime:
Failure of a link
Failure of a port or NIC
Failure of a networking device
Network engineers are often required to balance the cost of redundancy with the need for network availability.
Networks that demand close to 100 percent uptime often strive for “five nines” uptime, a network
that is available 99.999 percent of the time. A goal of redundant topologies is to eliminate network outages
caused by a single point of failure.
However, redundancy in switched topologies introduces a new problem called broadcast storms, which is
when frames loop endlessly through the network, eventually consuming all the available bandwidth.
Concept Questions
List and describe three of the problems that can occur with redundant links and devices in switched or
bridged networks.
■ Broadcast storms—Endless flooding of frames when no loop-avoidance technique is employed.
■ Multiple frame transmission—Multiple copies of unicast frames may cause unrecoverable errors.
■ MAC database instability—Results from copies of the same frame being received on different ports of
the switch.
What mechanism does the IP have to stop packets from endlessly looping throughout an internetwork?
IP uses an 8-bit field called the Time to Live (TTL) that is decremented by each router as the packet travels
from the source to the destination. If this field’s value reaches zero, the packet is dropped. Layer 2 has
no such mechanism.

Journal Entry
Chapter 7: Spanning Tree Protocol 315
Draw and label a topology with two switches. In your own words, explain how a broadcast storm would
occur in this redundantly switched network without some sort of mechanism to stop loops.
Any redundant switched topology is sufficient to illustrate loops. For example, Figure 7-1 is a basic redundant
topology. What you are looking for is a full understanding of what happens in a redundant switched
topology when no loop-avoidance mechanism is used—not just a reiteration of the steps listed in the
Companion Guide or the online curriculum. Have students orally explain how the loops occur.
Figure 7-1 Redundant Topology
Broadcast
Server/Host X
Switch A
Spanning Tree Protocol
Broadcast
Router Y
Segment 1
Switch B
Segment 2
STP is used in redundantly switched networks to create a loop-free logical topology from a physical topology
that has loops. The STP is a powerful tool that gives network administrators the security of a redundant
topology without the risk of problems caused by switching loops. In this section, you work through
exercises that will strengthen your understanding of what STP is and how it operates.

316 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Vocabulary Exercise: Matching
Match the definition on the left with a term on the right. This exercise is not necessarily a one-to-one
matching. Some definitions may be used more than once and some terms may have multiple definitions.
Definition
a. calculated based on the speed of the link
b. port is only receiving BPDUs
c. status messages sent between switches every
2 seconds
d. 20 seconds or a cycle of 10 BPDUs
e. the time it takes for a port to transition from
the listening state to the learning state or from
the learning state to the forwarding state
f. actively building a MAC address table but not
forwarding user traffic
g. used in redundantly switched networks to
create a loop-free logical topology
h. can send and receive traffic
i. port is sending and receiving BPDUs, but not
user traffic
j. without loop avoidance, frames are flooded
endlessly
k. includes the priority and MAC address of the
bridge
l. lowest-cost path from the non-root bridge to
the root bridge
m. an improved version of IEEE 802.1d
n. reduces the time of reconvergence when a
topology change occurs in a redundantly
switched network
o. called “blocking” in IEEE 802.1d
p. ports connected to a single end station
q. only one in a given network; all ports are
designated ports
r. operating in full-duplex mode
s. a port that is currently in the discarding state,
but will transition to forwarding if the designated
root port on that segment fails
t. automatically transitions from the blocking
state to the forwarding state
Term
j broadcast storms
g Spanning Tree Protocol (STP)
k bridge ID (BID)
a path cost
q root bridge
h designated ports
l root port
c bridge protocol data unit (BPDU)
g IEEE 802.1d
b blocking
i listening
f learning
e forward delay
d max-age
n, t PortFast
g, m, n Rapid Spanning Tree Protocol (RSTP)
s alternate port
o discarding state
g, m, n IEEE 802.1w
p edge ports
r point-to-point links

Vocabulary Exercise: Completion
Complete the paragraphs that follow by filling in appropriate words and phrases.
The Spanning Tree Protocol, originally developed by Digital Equipment Corporation, is used to maintain a
loop-free topology. STP is also known as IEEE 802.1d. STP builds a loop-free topology using two key
concepts: the bridge ID (BID) and path cost, which is based on the speed of the link. STP accumulates
cost based on the bandwidth of all the links in the path.
Originally, the cost of a link was calculated on a linear scale based on a maximum bandwidth of 1000
Mbps. Because LANs now incorporate 10GigE links, the costs have been revised. Complete the following
table showing the difference in IEEE costs for STP links.
Link Speed Cost (Revised IEEE Spec) Cost (Previous IEEE Spec)
10 Gbps 2 1
1 Gbps 4 1
100 Mbps 19 10
10 Mbps 100 100
Root ports and designated ports are used for forwarding data traffic. Nondesignated ports discard data traffic.
These ports are called blocking or discarding ports. When using STP, the root bridge is the bridge with
the lowest bridge ID (BID).
The BID is made up of two parts: the Priority field, which is 2 bytes, and MAC Address field, which is 6
bytes. The BID is included in messages that are sent every 2 seconds. These messages are called bridge
protocol data units (BPDUs).
Record the command, including the switch prompt, to change a switch’s priority from the default, which is
32768, to 4096. Assume that you are using IOS version 12.1 or later.
Switch(config)#spanning-tree vlan 1 priority 4096
If you do not configure priority, which switch in a given topology will be elected the root bridge?
The switch with the lowest MAC address will be elected the root bridge.
With STP, ports transition through four states: blocking, listening, learning, and forwarding. A fifth state,
disabled, is configured when the administrator manually shuts down the port. A port in the blocking state
listens only to BPDUs. If the port does not receive BPDUs for 20 seconds, which is the max-age timer,
then it transitions to the listening state. During the listening state, the port is sending and receiving BPDUs
to determine the active topology. After 15 seconds, which is called the forward delay, the port transitions
to the learning state. During the learning state, the port is actively building a MAC address table in preparation
for the forwarding state. After another forward delay of 20 seconds, the port transitions to the forwarding
state, in which it is either a root port or a designated port and is sending and receiving user traffic.
The total convergence time to move from a blocking state to a forwarding state is 50 seconds.
If a switch port is connected only to end-user stations, with no chance of ever connecting to another
switch, then it can be configured with the PortFast feature by using the spanning-tree portfast interface
command.
The Rapid Spanning Tree Protocol (RSTP), or IEEE 802.1w, was developed to reduce the time it takes to
reconverge the active topology when a change occurs. RSTP uses three port states: discarding, learning,
and forwarding. In addition, ports can have five different roles.
Note: Port roles are not the same as port states.
Chapter 7: Spanning Tree Protocol 317

318 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Complete the following table.
RSTP Role Definition
Root port A single port on each switch in which the switch hears the best BPDU out of all the
received BPDUs
Designated port Of all switch ports on all switches attached to the same segment/collision domain, the
port that advertises the “best” root BPDU
Alternate port A port on a switch that receives a suboptimal root BPDU
Backup port A nondesignated port on a switch that is attached to the same segment/collision
domain as another port on the same switch
Disabled A port that is administratively disabled
RSTP calls Ethernet connections between switches links and calls Ethernet connections to end-user
devices edges. If the link is full duplex, RSTP designates it as a point-to-point link. If the link is half
duplex, RSTP designates it as a shared link. An example of a shared link is a port attached to a hub.
Determine the Root Bridge and Port Roles Exercise
Instructor Note: This exercise will prove challenging for many students. However, you can enhance their understanding
of STP concepts and operation by reviewing the online curriculum for CCNP 3, Module 3: Objective 3.1,
“Defining the Spanning Tree Protocol—STP.”
The root bridge is chosen based on the lowest BID. After the root bridge is selected, a non-root bridge
looks at the following components in sequence to determine which ports will process user data and which
ports will discard user data:
1. On each non-root bridge, the port with the lowest path cost to root is the root port.
2. If two or more bridges are members of the same segment and have the same cost to reach the root
bridge, the bridge with the lowest BID is the designated port for that segment.
3. If a bridge has two or more equal cost paths to root, the port with the lowest ID is designated port.
The other port(s) is blocking.
In the topologies shown in Figures 7-2, 7-3, and 7-4, circle the root bridge. On non-root bridges, label root
ports with an R, designated ports with a D, and ports that are in the blocking state with a B. Use the
revised IEEE costs to make your determinations. In the space provided after each topology, draw the logical
loop-free spanning-tree topology with the root bridge at the top.

Figure 7-2 Determine the Root Bridge and Port Roles: Topology 1
I have the best BPDU.
I am root.
Both Gi0/1 and Gi0/2
have the same cost to
root, therefore Gi0/1
has the lower port ID
and is my root port.
Priority: Default
000d.ecdb.4be4
SWA
Gi0/1
D
Fa0/1
D
Gi0/2
D
100 Mbps
000e.385d.e380
Priority: Default
Root Bridge and Port Roles
1000 Mbps
R
Gi0/1
Gi0/2
1000 Mbps 1000 Mbps
Chapter 7: Spanning Tree Protocol 319
Priority: Default
000e.8362.e383
SWB
D Fa0/1
B
100 Mbps
B
Fa0/1
Gi0/2
B
R 1000 Mbps
Gi0/2
D
R
D
Fa0/1
SWC Gi0/1
Gi0/1 SWD
My path cost to root is lower
than SWC, therefore my
Gi0/1 is the designated port.
000d.edd3.37a3
Priority: Default
Logical, Loop-Free Spanning-Tree Topology
SWA
SWB SWD
SWC
My link cost to root is lower
than SWC, therefore my Gi0/2
is the designated port.
Although we have the same
cost to root, I have a lower
BID than SWB, therefore my
Fa0/1 is the designated port.

320 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure 7-3 Determine the Root Bridge and Port Roles: Topology 2
Although we have the same
cost to root, I have a lower
BID than SWC, therefore my
Fa0/1 is the designated port.
My path cost to root is lower
than SWD, therefore my Gi0/2
is the designated port.
Priority: Default
000d.ecdb.4be4
R
Gi0/1
SWA
D
Fa0/1 Gi0/2
D
100 Mbps
000e.385d.e380
Priority: 36,864
Root Bridge and Port Roles
1000 Mbps
Gi0/1
D
Gi0/2
1000 Mbps 1000 Mbps
Priority: 4096
000e.8362.e383
SWB
D Fa0/1
D
100 Mbps
B
Fa0/1
R
Gi0/2
D 1000 Mbps
Gi0/2
R
B
B
Fa0/1
SWC Gi0/1
Gi0/1 SWD
My path cost to root is lower
than SWD, therefore my
Gi0/1 is the designated port.
000d.edd3.37a3
Priority: Default
Logical, Loop-Free Spanning-Tree Topology
SWB
SWA SWC
SWD
I have the best BPDU.
I am root.
Both Gi0/1 and Gi0/2
have the same cost to
root, therefore Gi0/1
has the lower port ID
and is my root port.

Figure 7-4 Determine the Root Bridge and Port Roles: Topology 3
Priority: 45,056
My path cost to root is lower 000d.ecdb.4be4
than SWB, therefore my Gi0/1
D
is the designated port.
Gi0/1
SWA
R
Fa0/1 Gi0/2
B
Although we have the same
cost to root, I have a lower
BID than SWA, therefore my
Fa0/1 is the designated port.
100 Mbps
000e.385d.e380
Priority: Default
Root Bridge and Port Roles
1000 Mbps
1000 Mbps 1000 Mbps
Chapter 7: Spanning Tree Protocol 321
R
Gi0/1
Gi0/2
Priority: Default
000e.8362.e383
SWB
B Fa0/1
B
100 Mbps
D
Fa0/1
D
Gi0/2
R 1000 Mbps
Gi0/2
D
D
Fa0/1
SWC Gi0/1
Gi0/1
D
SWD
My path cost to root is lower
than SWB, therefore my
Gi0/2 is the designated port.
Logical, Loop-Free Spanning-Tree Topology
SWD
SWC SWA
1-58713-171-4
sl260704aa.eps
05/29/06
ICC
000d.edd3.37a3
Priority: 8192
SWB
Both Gi0/1 and Gi0/2
have the same cost to
root, therefore Gi0/1
has the lower port ID
and is my root port.
I have the best BPDU.
I am root.

322 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Spanning-Tree Recalculation Exercise
Figure 7-5 is the same as Figure 7-3 in the preceding section. However, now the Gigabit Ethernet link
between SWC and SWB has gone down. as indicated by the X. As you did before, circle the root bridge.
On non-root bridges, label root ports with an R, designated ports with a D, and ports that are in the blocking
state with a B. Use the revised IEEE costs to make your determinations. In the space provided after the
topology, draw the logical loop-free spanning-tree topology with the root bridge at the top.
Figure 7-5 Spanning-Tree Recalculation Exercise
None of my costs changed.
I am unaffected.
I lost my best path to
root. My next best path
is through SWD.
Priority: Default
000d.ecdb.4be4
R
Gi0/1
SWA
D
Fa0/1 Gi0/2
D
100 Mbps
B
Fa0/1
Gi0/2
R 1000 Mbps
Gi0/2
D
R
B
Fa0/1
SWC Gi0/1
Gi0/1 SWD
000e.385d.e380
Priority: 36,864
1000 Mbps
1000 Mbps
My path cost to root is now
lower than SWC, therefore my
Gi0/1 is the designated port.
1-58713-171-4
SWD
sl260705aa.eps
05/29/06
ICC
SWC
Priority: 4096
000e.8362.e383
Gi0/1
I have the best BPDU.
D SWB
I am root.
Gi0/2
D Fa0/1
D
1000 Mbps
New Loop-Free Spanning-Tree
Topology After Recalculation
SWB
SWA
100 Mbps
000d.edd3.37a3
Priority: Default
My Gi0/2 has the
lowest cost to root,
therefore it is now
the root port.

Concept Questions
What are the basic steps STP performs to converge a loop-free network?
1. The switches select the root bridge.
2. Configurations are made by the other switches and bridges, using the root bridge as a reference point.
3. Each bridge or switch determines which of its own ports offers the best path to the root bridge.
4. The logical loop is removed by one of the switches or bridges by blocking the port that creates the
logical loop. Blocking is done by calculating costs for each port in relation to the root bridge. Then
the port with the highest cost is disabled.
Note: Students may list more or fewer steps than shown here. Just make sure that the concepts are delineated.
How is the root bridge selected?
STP devices settle on the root bridge by using an administratively set priority number. The root bridge is
the one with the lowest priority number. The network administrator should always configure priority on
the desired root bridge.
What happens if two devices have the same priority number?
If this happens, the STP devices pick the one with the lowest MAC address.
What are BPDUs?
BPDUs are messages sent between the root bridge and the best ports on the other devices, which are called
root ports. The BPDUs transfer status messages about the network.
What happens if BPDUs are not received for a set amount of time?
Chapter 7: Spanning Tree Protocol 323
The non-root bridge devices will assume that the root bridge has failed, and a new root bridge will be
selected.

324 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Lab Exercises
Command Reference
In the table that follows, record the command, including the correct switch prompt, that fits the description
for a 2950 Catalyst switch. Fill in any blanks with the appropriate missing information.
Command Description
Switch#show spanning-tree brief Cisco IOS Software Release 12.0
Displays the spanning-tree table of the switch.
Switch#show spanning-tree Cisco IOS Software Release 12.1
Displays the spanning-tree table of the switch.
Switch(config)#spanning-tree priority 1 Cisco IOS Software Release 12.0
Sets the priority for root bridge elections.
Number can be from 1 to 65535. The default is
32768.
Switch(config)#spanning-tree vlan 1 priority 4096 Cisco IOS Software Release 12.1
Sets the priority for root bridge elections.
Number can be from 0 to 65535 and must be
configured in increments of 4096. The default
is 32768.
Switch(config-if)#spanning-tree portfast Sets an access port that will never be attached to
another switch to move immediately into the
forwarding state.
Curriculum Lab 7-1: Selecting the Root Bridge (7.2.4)
Figure 7-6 Topology for Lab 7-1
Table 7-1 Lab Equipment Configuration
FA0/1
FA0/1
FA0/7
FA0/4
FA0/4
FA0/8
Switch 1
Switch 2
Straight-Through Cable
Rollover (Console) Cable
Switch Designation Switch Name VLAN 1 IP Address Default Gateway IP
Address
Switch 1 Switch_A 192.168.1.2 192.168.1.1
Switch 2 Switch_B 192.168.1.3 192.168.1.1
The enable secret password for both switches is class.
Crossover Cable
Serial Cable

The enable, VTY, and console password for both switches is cisco.
The subnet mask for both switches is 255.255.255.0.
Objectives
■ Create a basic switch configuration and verify it.
■ Determine which switch is selected as a root switch with factory default settings.
■ Force the other switch to be selected as a root switch.
Background/Preparation
Cable a network that is similar to the one in Figure 7-6. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise:
■ Start a HyperTerminal session.
■ Implement the procedure that is documented in Appendix B, “Erasing and Reloading the Switch,” on
all switches before you continue with this lab.
Task 1: Configure the Switches
Configure the hostnames and passwords, as well as the management VLAN 1 settings for each switch, as
indicated in Table 7-1. If you have problems while performing this configuration, refer to Lab 6-2, “Basic
Switch Configuration.”
Task 2: Configure the Hosts that Are Attached to the Switches
Configure the hosts as part of the same subnet as the switches. The hosts also share the same subnet mask
and the same default gateway.
Task 3: Verify Connectivity
Step 1. To verify that the hosts and switches are correctly configured, ping the switches from the hosts.
C:\>ping 192.168.1.2
Pinging 192.168.1.2 with 32 bytes of data:
Reply from 192.168.1.2: bytes=32 time=1ms TTL=255
Reply from 192.168.1.2: bytes=32 time=1ms TTL=255
Reply from 192.168.1.2: bytes=32 time=1ms TTL=255
Reply from 192.168.1.2: bytes=32 time=1ms TTL=255
Ping statistics for 192.168.1.2:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 1ms, Maximum = 1ms, Average = 1ms
C:\>ping 192.168.1.3
Pinging 192.168.1.3 with 32 bytes of data:
Reply from 192.168.1.3: bytes=32 time=3ms TTL=255
Reply from 192.168.1.3: bytes=32 time=2ms TTL=255
Chapter 7: Spanning Tree Protocol 325

326 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Reply from 192.168.1.3: bytes=32 time=1ms TTL=255
Reply from 192.168.1.3: bytes=32 time=1ms TTL=255
Ping statistics for 192.168.1.3:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
C:\>
Minimum = 1ms, Maximum = 3ms, Average = 1ms
Step 2. Were the pings successful?
Step 3. If the answer is no, troubleshoot the host and switch configurations.
Note: If your pings were not successful, remember the troubleshooting methodology you learned in your CCNA 2
studies. Start with the physical layer first. Are all the link lights lit that need to be lit? What other Layer 1 issues might
be the problem? If Layer 1 is not the problem, proceed to Layer 2. What Layer 2 issues are likely to be causing a
problem? Layer 3? For a review of the method of testing by the layers, refer to the online curriculum CCNA 2 Routers
and Routing Basics: Module 9, Objective 9.2, “Network Testing.”
Task 4: Look at the show interface vlan Options
Step 1. Type show interface vlan1 ?.
Switch_A#show interface vlan1 ?
accounting Show interface accounting
capabilities Show interface capabilities information
counters Show interface counters
crb Show interface routing/bridging info
description Show interface description
etherchannel Show interface etherchannel information
fair-queue Show interface Weighted Fair Queueing (WFQ) info
flowcontrol Show interface flowcontrol information
irb Show interface routing/bridging info
mac-accounting Show interface MAC accounting info
precedence Show interface precedence accounting info
private-vlan Show interface private vlan information
pruning Show interface trunk VTP pruning information
random-detect Show interface Weighted Random Early Detection (WRED) info
rate-limit Show interface rate-limit info
shape Show interface Traffic Shape info
stats Show interface packets & octets, in & out, by switching
path
status Show interface line status
switchport Show interface switchport information
trunk Show interface trunk information
| Output modifiers
Step 2. List some of the options that are available.
counters, status, trunk

Task 5: Look at the VLAN Interface Information
Step 1. On Switch_A, type the command show interface vlan 1 at the privileged EXEC mode prompt.
Switch_A#show interface vlan 1
Vlan1 is up, line protocol is up
Hardware is CPU Interface, address is 0009.b7f5.6d80 (bia 0009.b7f5.6d80)
Internet address is 192.168.1.2/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:01:00, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 9000 bits/sec, 5 packets/sec
1184 packets input, 104481 bytes, 0 no buffer
Received 137 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
3439 packets output, 1160044 bytes, 0 underruns
0 output errors, 4 interface resets
0 output buffer failures, 0 output buffers swapped out
Step 2. What is the MAC address of the switch?
0009.b7f5.5a41
Step 3. On Switch_B, type the command show interface vlan 1 at the privileged EXEC mode prompt.
Step 4. What is the MAC address of the switch?
0009.b7f5.6d81
Step 5. Which switch should be the root of the spanning tree for VLAN 1?
Switch_A
Step 6. What would you do if you wanted to change which switch is root for VLAN 1?
Change the priority
True or False: After changing which switch is root, you must reload the switches for the change
to take effect.
False
Task 6: Look at the Switches’ Spanning-Tree Tables
Step 1. On Switch_A, type show spanning-tree brief at the privileged EXEC mode prompt if you are
running Cisco IOS Software Release 12.0. If you are running Cisco IOS Software Release
12.1, type show spanning-tree.
Switch_A#show spanning-tree brief
VLAN1
Spanning tree enabled protocol ieee
Root ID Priority 32768
Address 0009.b7f5.5a41
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Cost 19
Port 1 (FastEthernet0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32768
Address 0009.b7f5.6d81
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Designated
Name Port ID Prio Cost Sts Cost Bridge ID Port
ID
—————————— ———- —— —— —- ——- —————————— ———-
FastEthernet0/1 128.1 128 19 FWD 0 32768 0009.b7f5.5a41 128.1
FastEthernet0/4 128.4 128 19 BLK 0 32768 0009.b7f5.5a41 128.4
FastEthernet0/7 128.7 128 19 FWD 19 32768 0009.b7f5.6d81 128.7
Step 2. On Switch_B, type show spanning-tree brief at the privileged EXEC mode prompt.
Switch_B#show spanning-tree brief
VLAN1
Spanning tree enabled protocol ieee
Root ID Priority 32768
Address 0009.b7f5.5a41
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32768
Address 0009.b7f5.5a41
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Designated
Name Port ID Prio Cost Sts Cost Bridge ID Port
ID
—————————— ———- —— ——- —- ——- —————————— ———
FastEthernet0/1 128.1 128 19 FWD 0 32768 0009.b7f5.5a41 128.1
FastEthernet0/4 128.4 128 19 FWD 0 32768 0009.b7f5.5a41 128.4
FastEthernet0/8 128.8 128 19 FWD 0 32768 0009.b7f5.5a41 128.8
Step 3. Examine your output and answer the following questions.
Which switch is the root switch?
Switch_A
What is the priority of the root switch?
32768
What is the bridge ID of the root switch?
0009.b7f5.5a41
Which ports are forwarding on the root switch?
FastEthernet 0/1, 0/4, 0/7
Which ports are blocking on the root switch?
None

What is the priority of the non-root switch?
32768
What is the bridge ID of the non-root switch?
0009.b7f5.6d81
Which ports are forwarding on the non-root switch?
FastEthernet 0/1 and 0/8
Which ports are blocking on the non-root switch?
FastEthernet 0/4
What is the status of the link light on the blocking port?
Amber
Task 7: Reassign the Root Bridge
Step 1. The switch that has been selected as the root bridge, by using default values, is not the best
choice. You must force the other switch to become the root switch.
For the purposes of this step, assume that the root switch by default is Switch_A. Also assume
that Switch_B is preferred as the root switch. If your implementation has Switch_B as the
default root, then you will want to configure Switch_A to be the root. Go to the console and
enter configuration mode for the switch you want to change to root.
Step 2. Determine the parameters that you can configure for the STP.
Switch_A(config)#spanning-tree ?
backbonefast Enable BackboneFast Feature
etherchannel Spanning tree etherchannel specific configuration
extend Spanning Tree 802.1t extensions
loopguard Spanning tree loopguard options
mode Spanning tree operating mode
mst Multiple spanning tree configuration
pathcost Spanning tree pathcost options
portfast Spanning tree portfast options
uplinkfast Enable UplinkFast Feature
vlan VLAN Switch Spanning Tree
Step 3. List the options.
backbonefast, portfast, uplinkfast, vlan
Step 4. Set the priority of the switch that is not root to 4096.
If you are using Cisco IOS Software Release 12.0:
Switch_B(config)#spanning-tree priority 1
Switch_B(config)#exit
If you are using Cisco IOS Software Release 12.1:
Switch_B(config)#spanning-tree vlan 1 priority 4096
Switch_B(config)#exit
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Task 8: Look at the Switch Spanning-Tree Table
Step 1. On Switch_A, type show spanning-tree brief at the privileged EXEC mode prompt if you are
running Cisco IOS Software Release 12.0. If you are running Cisco IOS Software Release
12.1, type show spanning-tree.
Switch_A#show spanning-tree
VLAN1 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 4096, address 0009.b7f5.6d81
Configured hello time 2, max age 20, forward delay 15
We are the root of the spanning tree
Topology change flag not set, detected flag not set
Number of topology changes 4 last change occurred 00:01:34 ago
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 1, topology change 0, notification 0, aging 300
Port 1 (FastEthernet0/1) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.1.
Designated root has priority 4096, address 0009.b7f5.6d81
Designated bridge has priority 4096, address 0009.b7f5.6d81
Designated port id is 128.1, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 101, received 1436
Port 4 (FastEthernet0/4) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.4.
Designated root has priority 4096, address 0009.b7f5.6d81
Designated port id is 128.4, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 98, received 1433
Port 7 (FastEthernet0/7) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.7.
Designated root has priority 4096, address 0009.b7f5.6d81
Designated bridge has priority 4096, address 0009.b7f5.6d81
Designated port id is 128.7, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 2408, received 0
Step 2. On Switch_B, type show spanning-tree brief at the privileged EXEC mode prompt.
Step 3. Examine your output and answer the following questions.
Which switch is the root switch?
Switch_B
What is the priority of the root switch?
4096

Which ports are forwarding on the root switch?
FastEthernet 0/1, 0/4, and 0/8
Which ports are blocking on the root switch?
None
What is the priority of the non-root switch?
32768
Which ports are forwarding on the non-root switch?
FastEthernet 0/1 and 0/7
Which ports are blocking on the non-root switch?
FastEthernet 0/4
What is the status of the link light on the blocking port?
Amber
Task 9: Verify the Running Configuration File on the Root Switch
Step 1. On the switch that was changed to be the root bridge, type show running-config at the
privileged EXEC mode prompt.
Switch_A#show running-config
Building configuration...
Current configuration : 1233 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Switch_A
!
enable secret 5 $1$K0Nw$Vfv.yuMmf20yNpzBO3uOh0
!
ip subnet-zero
no ip finger
!
spanning-tree vlan 1 priority 4096
!
interface FastEthernet0/1
!
!
interface FastEthernet0/24
!
interface Vlan1
ip address 192.168.1.2 255.255.255.0
no ip route-cache
!
ip default-gateway 192.168.1.1
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ip http server
!
line con 0
password cisco
login
transport input none
line vty 0 4
password cisco
login
line vty 5 15
!
end
password cisco
login
Step 2. Does an entry exist in the running configuration file that specifies the spanning-tree priority for
this switch?
Yes
Step 3. What does that entry say?
spanning-tree vlan 1 priority 4096
Note: The output is different depending on whether the Cisco IOS software is Release 12.0 or Release 12.1.
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then remove
and store the cables and adapter.
Curriculum Lab 7-2: Spanning-Tree Recalculation (7.2.6)
Figure 7-7 Topology for Lab 7-2
Table 7-2 Lab Equipment Configuration
FA0/1
FA0/7 FA0/4
FA0/4
FA0/8
Switch 1
Switch 2
Straight-Through Cable
Rollover (Console) Cable
Switch Designation Switch Name VLAN 1 IP Address Default Gateway IP Address
Switch 1 Switch_A 192.168.1.2 192.168.1.1
Switch 2 Switch_B 192.168.1.3 192.168.1.1
The enable secret password for both switches is class.
The enable, VTY, and console password for both switches is cisco.
The subnet mask for both switches is 255.255.255.0.
FA0/1
Crossover Cable
Serial Cable

Objectives
■ Create a basic switch configuration and verify it.
■ Observe the behavior of the spanning-tree algorithm in the presence of switched network topology
changes.
Background/Preparation
Cable a network that is similar to the one in Figure 7-7. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise:
■ Start a HyperTerminal session.
■ Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switches
Configure the hostnames and passwords, as well as the management VLAN 1 settings for each switch, as
indicated in Table 7-2. If you have problems while performing this configuration, refer to Lab 6-2, “Basic
Switch Configuration.”
Task 2: Configure the Hosts that Are Attached to the Switches
Configure the hosts as part of the same subnet as the switches. The hosts also share the same subnet mask
and the same default gateway.
Task 3: Verify Connectivity
Step 1. To verify that the hosts and switches are configured correctly, ping the switches from the hosts.
Step 2. Were the pings successful?
Step 3. If the answer is no, troubleshoot the host and switch configurations.
Task 4: Look at the VLAN Interface Information
Step 1. On both switches, type the command show interface vlan 1 at the privileged EXEC prompt.
Switch_A#show interface vlan 1
Vlan1 is up, line protocol is up
Hardware is CPU Interface, address is 0009.b7f5.6d80 (bia 0009.b7f5.6d80)
Internet address is 192.168.1.2/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:02:05, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 3000 bits/sec, 5 packets/sec
5 minute output rate 6000 bits/sec, 1 packets/sec
1453 packets input, 104542 bytes, 0 no buffer
Received 10 broadcasts, 0 runts, 0 giants, 0 throttles
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0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
375 packets output, 189108 bytes, 0 underruns
0 output errors, 4 interface resets
0 output buffer failures, 0 output buffers swapped out
Switch_B#show interface vlan 1
Vlan1 is up, line protocol is up
Hardware is CPU Interface, address is 0009.b7f5.5a40 (bia 0009.b7f5.5a40)
Internet address is 192.168.1.3/24
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:02:27, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 0 bits/sec, 1 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
9119 packets input, 648668 bytes, 0 no buffer
Received 76 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
17084 packets output, 611644 bytes, 0 underruns
0 output errors, 4 interface resets
0 output buffer failures, 0 output buffers swapped out
Step 2. What is the MAC address of Switch_A?
0009.b7f5.6d80
Step 3. What is the MAC address of Switch_B?
0009.b7f5.5a40
Step 4. Which switch should be the root of the spanning tree for VLAN 1?
Switch_B
Task 5: Look at the Switches’ Spanning-Tree Tables
Step 1. On Switch_A, type show spanning-tree brief at the privileged EXEC mode prompt if you
are running Cisco IOS Software Release 12.0. If you are running Cisco IOS Software Release
12.1, type show spanning-tree. Different releases of IOS have different options for this
command.
Switch_A#show spanning-tree
VLAN1 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address 0009.b7f5.6d81
Configured hello time 2, max age 20, forward delay 15
Current root has priority 32768, address 0009.b7f5.5a41
Root port is 1 (FastEthernet0/1), cost of root path is 19
Topology change flag not set, detected flag not set
Number of topology changes 1 last change occurred 00:10:00 ago
from FastEthernet0/1
Times: hold 1, topology change 35, notification 2

hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0, aging 300
Port 1 (FastEthernet0/1) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.1.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.5a41
Designated port id is 128.1, designated path cost 0
Timers: message age 1, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 1, received 316
Port 4 (FastEthernet0/4) of VLAN1 is blocking
Port path cost 19, Port priority 128, Port Identifier 128.4.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.5a41
Designated port id is 128.4, designated path cost 0
Timers: message age 1, forward delay 0, hold 0
Number of transitions to forwarding state: 0
BPDU: sent 2, received 316
Port 7 (FastEthernet0/7) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.7.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.6d81
Designated port id is 128.7, designated path cost 19
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 316, received 0
Step 2. On Switch_B, type show spanning-tree brief at the privileged EXEC mode prompt.
Switch_B#show spanning-tree
VLAN1 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address 0009.b7f5.5a41
Configured hello time 2, max age 20, forward delay 15
We are the root of the spanning tree
Topology change flag not set, detected flag not set
Number of topology changes 5 last change occurred 00:10:48 ago
from FastEthernet0/1
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 1, topology change 0, notification 0, aging 300
Port 1 (FastEthernet0/1) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.1.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.5a41
Designated port id is 128.1, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 679, received 1
Port 4 (FastEthernet0/4) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.4.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.5a41
Designated port id is 128.4, designated path cost 0
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Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 679, received 1
Port 8 (FastEthernet0/8) of VLAN1 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.8.
Designated root has priority 32768, address 0009.b7f5.5a41
Designated bridge has priority 32768, address 0009.b7f5.5a41
Designated port id is 128.8, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 2247, received 0
Step 3. Examine the command output and answer the following questions.
Which switch is the root switch?
Switch_B
Record the states of the first 12 interfaces and ports of each switch in the following table.
Switch_A Port No. Switch_B
FWD 1 FWD
Down 2 Down
Down 3 Down
BLK 4 FWD
Down 5 Down
Down 6 Down
FWD 7 Down
Down 8 FWD
Down 9 Down
Down 10 Down
Down 11 Down
Down 12 Down
Task 6: Remove a Cable on the Switch
Step 1. Remove the cable from the forwarding port on the non-root switch. If Switch_A is your root
switch, then remove the cable from the forwarding port on Switch_B. If Switch_B is your root
switch, then remove the cable from the forwarding port on Switch_A.
Step 2. Wait for at least 2 minutes.
Step 3. What has happened to the switch port LEDs?
The port LEDs on both switches for FastEthernet 0/1 turned off.

Task 7: Look at the Spanning-Tree Table for the Switches
Step 1. On Switch_A, type show spanning-tree brief at the privileged EXEC mode prompt if you
are running Cisco IOS Software Release 12.0. If you are running Cisco IOS Software Release
12.1, type show spanning-tree. Different releases of IOS have different options for this
command.
Switch_A#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0009.b7f5.5a40
Cost 19
Port 4 (FastEthernet0/4)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0009.b7f5.6d80
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port
ID
Name Prio.Nbr Cost Sts Cost Bridge ID
Prio.Nbr
———————— ———— ————- —- ————- —————————— ————
Fa0/4 128.4 19 FWD 0 32769 0009.b7f5.5a40 128.4
Fa0/7 128.7 19 FWD 0 32769 0009.b7f5.5a40 128.7
Step 2. On Switch_B, type show spanning-tree brief at the privileged EXEC mode prompt.
Switch_B#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0009.b7f5.5a40
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0009.b7f5.5a40
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port
ID
Name Prio.Nbr Cost Sts Cost Bridge ID
Prio.Nbr
———————— ———— ————- —- ————- —————————— ————
Fa0/4 128.4 19 FWD 0 32769 0009.b7f5.5a40 128.4
Fa0/8 128.8 19 FWD 0 32769 0009.b7f5.5a40 128.8
Step 3. What changes have taken place in the command output?
On Switch_A?
Information and statistics for FastEthernet 0/1 are not displayed and FastEthernet 0/4 went
from BLK mode into FWD mode.
On Switch_B?
Information and statistics for FastEthernet 0/1 are not displayed.
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Task 8: Replace the Cable in the Switch
Step 1. Replace the cable in the port that it was removed from. For the previous example, this is interface
FastEthernet 0/1 on Switch_A.
Step 2. Wait for at least 2 minutes.
Step 3. What has happened to the switch port LEDs?
Both light up green.
Task 9: Redisplay the Spanning-Tree Table for the Switches
Step 1. On Switch_A, type show spanning-tree brief at the privileged EXEC mode prompt if you
are running Cisco IOS Software Release 12.0. If you are running Cisco IOS Software Release
12.1, type show spanning-tree. Different releases of IOS have different options for this
command.
Switch_A#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0009.b7f5.5a40
Cost 19
Port 1 (FastEthernet0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0009.b7f5.6d80
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port
ID
Name Prio.Nbr Cost Sts Cost Bridge ID
Prio.Nbr
———————— ———— ————- —- ————- —————————— ————
Fa0/1 128.1 19 FWD 0 32769 0009.b7f5.5a40 128.1
Fa0/4 128.4 19 BLK 0 32769 0009.b7f5.5a40 128.4
Fa0/7 128.7 19 FWD 0 32769 0009.b7f5.5a40 128.7
Step 2. On Switch_B, type show spanning-tree brief at the privileged EXEC mode prompt.
Switch_B#show spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32769
Address 0009.b7f5.5a40
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 0009.b7f5.5a40
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Interface Port ID Designated Port
ID
Name Prio.Nbr Cost Sts Cost Bridge ID
Prio.Nbr

———————— ———— ————- —- ————- —————————— ————
Fa0/1 128.1 19 FWD 0 32769 0009.b7f5.5a40 128.1
Fa0/4 128.4 19 FWD 0 32769 0009.b7f5.5a40 128.4
Fa0/8 128.8 19 FWD 0 32769 0009.b7f5.5a40 128.8
Step 3. What changes have taken place in the command output?
On Switch_A?
FastEthernet 0/1 goes back into FWD mode and FastEthernet 0/4 went back to BLK mode.
On Switch_B?
FastEthernet 0/1 goes back into FWD mode.
Chapter 7: Spanning Tree Protocol 339
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then remove
and store the cables and adapter.

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CHAPTER 8
Virtual LANs
The Study Guide portion of this chapter uses a combination of fill in the blank and unique custom exercises
to test your knowledge on the theory of VLANs, VLAN configuration, and VLAN troubleshooting.
The Lab Exercises portion of this chapter includes all of the online curriculum labs as well as a challenge
lab to ensure that you have mastered the practical, hands-on skills needed about VLANs.

342 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
VLAN Concepts
As a network engineer, it is important that you understand the logical function of a VLAN and how
VLANs can improve network performance. The completion exercise in this brief section provides a quick
review of VLAN concepts.
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
Up to this point in your studies, you have learned that a LAN includes all devices in the same broadcast
domain and that a switch is used to microsegment the collision domain. In this chapter, you learned that
switches can be configured with virtual LANs, or VLANs, to segment the broadcast domain at Layer 2.
Without VLANs, a switch treats all interfaces on the switch as being in the same broadcast domain.
A VLAN is a broadcast domain created by one or more switches. Configuration is as simple as putting
some interfaces in one VLAN and other interfaces in another VLAN.
List a few reasons or benefits for using VLANs:
■ Limit the size of broadcast domains
■ Group users by function, department, or some other logic instead of by physical location
■ Increase security by separating logically devices on the same LAN
■ Separate specialized traffic from user traffic (e.g. IP phones)
Layer 2 switches cannot forward traffic between VLANs. In fact, the switch maintains a separate MAC
address table for each VLAN so that broadcasts are contained within each VLAN. To communicate
between users on different VLANs, the traffic must pass through a router or Layer 3 switch. This can be
done by using a different Ethernet interface for each VLAN. Note that each VLAN would be on a different
subnet. It is more common to use one Fast Ethernet interface to trunk multiple VLANs and configure logical
subinterfaces.
Two basic VLAN configuration methods are available to the network engineer: static configuration, which
is port based, and dynamic configuration, which uses a VLAN Management Policy Server (VMPS). Static
VLAN configuration is by far the most widely implemented of these two methods. Dynamic VLAN configuration
is not currently a CCNA objective.
VLAN Configuration
Currently, the Cisco IOS is in a transition phase from configuring VLANs in VLAN database configuration
mode to configuring VLANs in global configuration mode. Because both ways are currently supported,
you need to be familiar with each. The configuration exercise in this section will walk you through
both methods for creating, modifying, applying, and deleting VLANs.
Learn VLAN Configuration Commands Exercise
True or False: You can assign a VLAN to an interface without creating the VLAN first. If true, what confirmation
message does the switch display? If false, what error message does the switch display?

True
SWA(config)#interface fa0/4
SWA(config-if)#switchport access vlan 40
% Access VLAN does not exist. Creating vlan 40
Chapter 8: Virtual LANs 343
VLANs can be created using VLAN database mode or global configuration mode. VLAN global configuration
mode is preferred because the user interface is familiar. In addition, you must use the exit command
in VLAN database mode to have changes applied to the VLAN database. Finally, VLAN database configuration
mode has been deprecated and will be removed in some future releases.
For the following exercise, refer to Figure 8-1.
Figure 8-1 VLAN Configuration Commands
Record the commands, including the switch prompt, to configure SWA with the VLANs, shown in Figure
8-1. The commands would be the same on SWB.
VLAN database configuration mode
SWA#vlan database
SWA(vlan)#vlan 10 name Accounting
VLAN 10 added:
Name: Accounting
SWA(vlan)#vlan 20 name Marketing
VLAN 10 added:
Name: Marketing
SWA(vlan)#vlan 30 name Purchasing
VLAN 10 added:
Name: Purchasing
SWA(vlan)#exit
APPLY completed.
Exiting....
SWA#
VLAN 1 10.1.0.0/16
VLAN 10 10.10.0.0/16
VLAN 20 10.20.0.0/16
VLAN 30 10.30.0.0/16
VLAN 10
fa0/4–8
VLAN global configuration mode
SWA(config)#vlan 10
SWA(config-vlan)#name Accounting
SWA(config-vlan)#vlan 20
SWA(config-vlan)#name Marketing
SWA(config-vlan)#vlan 30
VLAN 1: 10.1.0.2
DefGate: 10.1.0.1
SWA
VLAN 20
fa0/9–16
fa0/2
fa0/3
VLAN 30
fa0/17–24
VLAN 10
fa0/4–8
VLAN 1: 10.1.0.3
DefGate: 10.1.0.1
fa0/2
SWB
fa0/3
VLAN 20
fa0/9–16
VLAN 30
fa0/17–24

344 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
SWA(config-vlan)#name Purchasing
SWA(config-vlan)#end
SWA#
From global configuration mode if you type interface ? and see range as one of the options, you are in
luck. Your Cisco IOS Software Release supports the range parameter. This argument to the interface command
allows you to configure multiple ports at one time. For example:
Switch(config)#interface range fa0/1 – 8
Switch(config-if-range)#
Interestingly, the hyphen is considered a parameter. You must enter a space before and after the hyphen.
Note that the range argument can be used to configure any combination of ports. For example, the following
would be a legitimate command:
Switch(config)#interface range fa 0/4 - 5, fa 0/3 , fa 0/10 - 12 , gi 0/1
Switch(config-if-range)#
Record the commands, including the switch prompt, to assign interfaces with the VLANs shown in Figure
8-1. You only need to show the commands for SWA. The commands are the same for SWB.
SWA(config)#interface range fa 0/4 – 8
SWA(config-if-range)#switchport mode access
SWA(config-if-range)#switchport access vlan 10
SWA(config-if-range)#interface range fa 0/9 – 16
SWA(config-if-range)#switchport mode access
SWA(config-if-range)#switchport access vlan 20
SWA(config-if-range)#interface range fa 0/17 - 24
SWA(config-if-range)#switchport mode access
SWA(config-if-range)#switchport access vlan 30
SWA(config-if-range)#end
SWA#
You need to move ports Fa0/17 through Fa0/20 to the Marketing VLAN. Record the command or commands,
including switch prompt, to make the move.
SWA(config)#interface range fa 0/17 – 20
SWA(config-if-range)#switchport access vlan 20
!You do not need to first remove the ports from the other VLAN
The Purchasing department has been eliminated. All Purchasing department functions are now handled by
Accounting. You no longer need the Purchasing VLAN. Record the command or commands, including
switch prompt, to delete the Purchasing VLAN.
VLAN database configuration mode
Switch#vlan database
Switch(vlan)#no vlan 10
Deleting VLAN 10...
Switch(vlan)#exit
APPLY completed.
Exiting....
Switch#

VLAN global configuration mode
Switch(config)#no vlan 10
Switch(config)#exit
Switch#
What happens to the ports that were members of a deleted VLAN?
The ports belong to no VLAN and will have only limited access.
What must be done to fix this problem?
Either assign the ports to a new VLAN or use the no form of the switchport access vlan command to reassign
the ports to VLAN 1.
Record the commands, including switch prompt, to reassign ports Fa0/21 through Fa0/24 to VLAN 1.
SWA(config)#interface range fa 0/21 – 24
SWA(config-if-range)#no switchport mode access vlan
!or
SWA(config-if-range)#switchport mode access vlan 1
Troubleshooting VLANs
Now that you are comfortable configuring VLANS, it is time to review the commands that will help you to
verify and troubleshoot your VLAN implementation. This section covers the show commands most commonly
used with VLANs.
Identify the Troubleshooting Command Exercise
In this exercise, you are asked to identify what command was used to display the output. You may need to
use a switch to help research your answers. The following output is from a Cisco 2950 running Cisco IOS
Software Version 12.1(13)EA1.
Switch#show spanning-tree vlan 1
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 4097
Address 000e.385d.e380
This bridge is the root
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 4097 (priority 4096 sys-id-ext 1)
Address 000e.385d.e380
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Chapter 8: Virtual LANs 345
Interface Role Sts Cost Prio.Nbr Type
———————— —— —- ————- ———— ————————————————
Fa0/1 Desg FWD 19 128.1 P2p
Fa0/2 Desg FWD 19 128.2 P2p

346 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Fa0/3 Desg FWD 19 128.3 P2p
Switch#show vlan name Accounting !or show vlan id 10
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
10 Accounting active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
10 enet 100010 1500 - - - - - 0 0
Remote SPAN VLAN
————————
Disabled
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Switch#show interface fa0/2 switchport
Name: Fa0/2
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Voice VLAN: none (Inactive)
Appliance trust: none

Switch#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Gi0/1, Gi0/2
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Switch#show interface trunk
Port Mode Encapsulation Status Native vlan
Fa0/1 on 802.1q trunking 1
Fa0/2 on 802.1q trunking 1
Fa0/3 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/1 1-4094
Fa0/2 1-4094
Fa0/3 1-4094
Port Vlans allowed and active in management domain
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Port Vlans in spanning tree forwarding state and not pruned
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,30
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348 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Lab Exercises
Command Reference
In the table that follows, record the command, including the correct switch prompt, that fits the description
for a 2950 Catalyst switch.
Command Description
Switch#vlan database Enters VLAN database configuration mode
Switch(vlan)#vlan 2 name Engineering Creates VLAN 2 and names it Engineering
Switch(vlan)#vlan 3 name Marketing Creates VLAN 2 and names it Marketing
Switch(vlan)#exit Applies changes and exits VLAN database mode
Switch(config)#vlan 10 Creates VLAN 10 using global configuration mode
Switch(config-vlan)#name Accounting Assigns the name Accounting to VLAN 10
Switch(config)#interface range fa0/2 – 8 Enters interface configuration mode for interfaces Fa0/2
through Fa0/8
Switch(config)#switchport mode access Sets these ports to access mode
Switch(config-if)#switchport access vlan 2 Assigns these ports to VLAN 2
Switch(vlan)#no vlan 3 Deletes VLAN 3 in VLAN database configuration mode
Switch(config)#no vlan 3 Deletes VLAN 3 in global configuration mode
Switch(config-if)#no switchport access vlan 10 Removes an interface from VLAN 10
Switch#delete flash:vlan.dat Removes the entire VLAN database from Flash memory
Switch#show vlan Displays the complete VLAN database
Switch#show vlan brief Displays a summary of the VLAN database
Curriculum Lab 8-1: Configuring Static VLANs (8.2.3)
Figure 8-2 Topology for Lab 8-1
Table 8-1 Lab Equipment Configuration
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable
Switch Switch Name VLAN 1 IP Address Default Gateway Subnet Mask
Designation IP Address
Switch 1 Switch_A 192.168.1.2 192.168.1.1 255.255.255.0

The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create a basic switch configuration and verify it.
■ Determine the switch firmware version.
■ Create two VLANs, name them, and assign member ports to them.
Background/Preparation
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default. This lab will help demonstrate how you can use VLANs to separate traffic and reduce
broadcast domains.
Cable a network that is similar to the one in Figure 8-2. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B, “Erasing and Reloading the Switch,” on all switches
before you continue with this lab.
Task 1: Configure the Switch
Configure the hostnames and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 8-1. If you have problems while performing this configuration, refer to Lab 6-2, “Basic
Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Show the Cisco IOS Version
It is important that you know the version of the operating system. Differences between versions might
change how you enter commands. Enter the show version command at the user EXEC or privileged
EXEC mode prompt.
Switch_A#show version
What version of the switch IOS is displayed? 12.1(13)EA1
Does this switch have Standard Edition or Enterprise Edition software? Standard
Switch_A#show version
Chapter 8: Virtual LANs 349

350 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1, RELEASE
SOFTWARE (fc1)
Copyright 1986-2003 by cisco Systems, Inc.
Compiled Tue 04-Mar-03 02:14 by yenanh
Image text-base: 0x80010000, data-base: 0x805A8000
ROM: Bootstrap program is CALHOUN boot loader
Switch_A uptime is 7 minutes
System returned to ROM by power-on
System image file is “flash:c2950-i6q4l2-mz.121-13.EA1.bin”
cisco WS-C2950-24 (RC32300) processor (revision E0) with 20839K bytes of
memory.
Processor board ID FHK0634Z08M
Last reset from system-reset
Running Standard Image
24 FastEthernet/IEEE 802.3 interface(s)
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:0A:B7:72:2B:40
Motherboard assembly number: 73-5781-10
Power supply part number: 34-0965-01
Motherboard serial number: FOC06330DJG
Power supply serial number: PHI06290B8Q
Model revision number: E0
Motherboard revision number: B0
Model number: WS-C2950-24
System serial number: FHK0634Z08M
Configuration register is 0xF
Task 5: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Which ports belong to the default VLAN? All
How many VLANs are set up by default on the switch? 5
What does the VLAN 1003 represent?
It represents the default Token Ring VLAN.
How many ports are in the 1003 VLAN? 0
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16

1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 6: Create and Name Two VLANs
Enter the following commands to create two named VLANs:
Switch_A#vlan database
Switch_A(vlan)#vlan 2 name VLAN2
Switch_A(vlan)#vlan 3 name VLAN3
Switch_A(config)#exit
1900:
Switch_A#config t
Switch_A(config)#vlan 2 name VLAN2
Switch_A(config)#vlan 3 name VLAN3
Task 7: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are new VLANs in the listing? If so, which ones? Yes, 2 and 3
Do these VLANs have ports assigned to them yet? No
Switch_A#show vlan
VLAN Name Status Ports
Chapter 8: Virtual LANs 351
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4

352 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
2 VLAN2 active
3 VLAN3 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 8: Assign a Port to VLAN 2
You must assign ports to VLANs from the interface mode. Enter the following commands to add port 2 to
VLAN 2:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/2
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface Ethernet 0/2
Switch_A(config-if)#vlan static 2
Switch_A(config)#end

Task 9: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Is port 2 assigned to VLAN 2? Yes
Is the port still listed in the default VLAN? No
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/3, Fa0/4, Fa0/5
2 VLAN2 active Fa0/2
3 VLAN3 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/6, Fa0/7, Fa0/8, Fa0/9
Fa0/10, Fa0/11, Fa0/12, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
Chapter 8: Virtual LANs 353
———- ————- ————————- —————————————————————

354 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 10: Assign a Port to VLAN 3
You must assign ports to VLANs from the interface mode. Enter the following commands to add port 3 to
VLAN 3:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/3
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface Ethernet 0/3
Switch_A(config)#vlan static 3
Switch_A(config)#end
Task 11: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Is port 3 assigned to VLAN 3? Yes
Is the port still listed in the default VLAN? No
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/4, Fa0/5, Fa0/6
2 VLAN2 active Fa0/2
3 VLAN3 active Fa0/3
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/7, Fa0/8, Fa0/9, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 12: Look Only at VLAN 2 Information
Instead of displaying all the VLANs, enter the show vlan id 2 command at the privileged EXEC mode
prompt.
Switch_A#show vlan id 2
1900:
Switch_A#show vlan 2
Does this command supply more information than the show vlan command? Yes
Switch_A#show vlan id 2
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
2 VLAN2 active Fa0/2
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
2 enet 100002 1500 - - - - - 0 0
Remote SPAN VLAN
————————
Disabled
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 13: Look Only at VLAN 2 Information with a Different
Command (1900: Skip this Task)
Instead of displaying all the VLANs, enter the show vlan name VLAN2 command at the privileged
EXEC mode prompt.
Switch_A#show vlan name VLAN2
Chapter 8: Virtual LANs 355

356 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Does this command supply more information than the other show commands? No
ALSwitch#show vlan name VLAN2
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
2 VLAN2 active Fa0/2
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
2 enet 100002 1500 - - - - - 0 0
Remote SPAN VLAN
————————
Disabled
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
After you complete the previous step, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.
Curriculum Lab 8-2: Verifying VLAN Configurations
(8.2.4)
Figure 8-3 Topology for Lab 8-2
Table 8-2 Lab Equipment Configuration
Switch Switch Name VLAN 1 IP Address Default Gateway Subnet Mask
Designation IP Address
Switch 1 Switch_A 192.168.1.2 192.168.1.2 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create a basic switch configuration and verify it.
■ Create two VLANs.
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable

■ Name the VLANs and assign multiple member ports to them.
■ Test functionality by moving a workstation from one VLAN to another.
Background/Preparation
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default. This lab will also help demonstrate how VLANs can be used to separate traffic and
reduce broadcast domains.
Cable a network that is similar to the one in Figure 8-3. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise. Instructions are also provided for the 1900
series switch, which initially displays a User Interface Menu. Select the Command Line option from the
menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switch
Configure the hostnames and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 8-2. If you have problems while performing this configuration, refer to Lab 6-2, “Basic
Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Which ports belong to the default VLAN? All
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
1002 fddi-default act/unsup
Chapter 8: Virtual LANs 357
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24

358 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 5: Create and Name Two VLANs
Enter the following commands to create two named VLANs:
Switch_A#vlan database
Switch_A(vlan)#vlan 2 name VLAN2
Switch_A(vlan)#vlan 3 name VLAN3
Switch_A(config)#exit
1900:
Switch_A#config t
Switch_A(config)#vlan 2 name VLAN2
Switch_A(config)#vlan 3 name VLAN3
Switch_A(config)#exit
Task 6: Assign Ports to VLAN 2
You must assign ports to VLANs from the interface mode. Enter the following commands to add ports 4,
5, and 6 to VLAN 2:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config)#interface fastethernet 0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config)#interface fastethernet 0/6

Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface ethernet 0/4
Switch_A(config-if)#vlan static 2
Switch_A(config-if)#interface ethernet 0/5
Switch_A(config-if)#vlan static 2
Switch_A(config-if)#interface ethernet 0/6
Switch_A(config-if)#vlan static 2
Switch_A(config-if)#end
Task 7: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 4 through 6 assigned to VLAN 2? Yes
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/7
Fa0/8, Fa0/9, Fa0/10, Fa0/11
Fa0/12, Fa0/13, Fa0/14, Fa0/15
Fa0/16, Fa0/17, Fa0/18, Fa0/19
Fa0/20, Fa0/21, Fa0/22, Fa0/23
Fa0/24
2 VLAN2 active Fa0/4, Fa0/5, Fa0/6
3 VLAN3 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Chapter 8: Virtual LANs 359
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———

360 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- ————————————————————-
Task 8: Assign Ports to VLAN 3
Enter the following commands to assign ports 7, 8, and 9 to VLAN 3:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/7
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config)#interface fastethernet 0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config)#interface fastethernet 0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config-if)#end
Task 9: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 7 through 9 assigned to VLAN 3? Yes
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24
2 VLAN2 active Fa0/4, Fa0/5, Fa0/6
3 VLAN3 active Fa0/7, Fa0/8, Fa0/9
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup

VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 10: Test the VLANs
Step 1. Ping from the host in port 0/4 to the host in port 0/1.
Was the ping successful? No
Why?
They have different VLAN membership.
Step 2. Ping from the host in port 0/1 to the host in port 0/4.
Was the ping successful? No
Why?
They have different VLAN membership.
Step 3. Ping from the host in port 0/4 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
They have different VLAN membership.
Step 4. Ping from the host in port 0/1 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
They have the same VLAN membership.
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362 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 11: Move a Host
Move the host in port 0/4 to port 0/3, wait until the port LED turns green, and then go to the next task.
Task 12: Test the VLANs
Step 1. Ping from the host in port 0/3 to the host in port 0/1.
Was the ping successful? Yes
Why?
They have the same VLAN membership.
Step 2. Ping from the host in port 0/1 to the host in port 0/3.
Was the ping successful? Yes
Step 3. Ping from the host in port 0/3 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Task 13: Move Hosts
Move the host in port 0/3 to port 0/4 and the host in port 0/1 to port 0/5, wait until the port LED turns
green, and then go to the next task.
Task 14: Test the VLANs
Step 1. Ping from the host in port 0/4 to the host in port 0/5.
Was the ping successful? Yes
Why?
They have the same VLAN membership.
Step 2. Ping from the host in port 0/5 to the host in port 0/4.
Was the ping successful? Yes
Step 3. Ping from the host in port 0/4 to the switch IP 192.168.1.2.
Was the ping successful? No
Step 4. Ping from the host in port 0/5 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
They have different VLAN membership.
Task 15: Move the Hosts
Move the host in port 0/4 to port 0/8, wait until the port LED turns green, and then go to the next task.
Task 16: Test the VLANs
Step 1. Ping from the host in port 0/4 to the host in port 0/8.
Was the ping successful? No

Why?
They have different VLAN membership.
Step 2. Ping from the host in port 0/8 to the host in port 0/4.
Was the ping successful? No
Step 3. Ping from the host in port 0/4 to the switch IP 192.168.1.2.
Was the ping successful? No
Step 4. Ping from the host in port 0/8 to the switch IP 192.168.1.2.
Was the ping successful? No
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.
Curriculum Lab 8-3: Deleting VLAN Configurations (8.2.6)
Figure 8-4 Topology for Lab 8-3
Table 8-3 Lab Equipment Configuration
Switch Switch Name VLAN 1 IP Address Default Gateway Subnet Mask
Designation IP Address
Switch 1 Switch_A 192.168.1.2 192.168.1.1 255.255.255.0
The enable secret password is class.
The enable, VTY, and console password is cisco.
Objectives
■ Create a basic switch configuration and verify it.
■ Create two VLANs.
■ Name the VLANs and assign multiple member ports to them.
■ Delete VLANs.
■ Understand why it is not possible to delete VLAN 1.
Background/Preparation
FA0/1 FA0/4
Switch 1
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable
Chapter 8: Virtual LANs 363
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default. This lab will help demonstrate how you can use VLANs to separate traffic and reduce
broadcast domains.
Cable a network that is similar to the one in Figure 8-4. The 2950 series switch produced the configuration
output in this lab. Another switch might produce different output. You should execute the following steps
on each switch unless you are specifically instructed otherwise.

364 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Instructions are also provided for the 1900 series switch, which initially displays a User Interface Menu.
Select the Command Line option from the menu to perform the steps for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B on all switches before you continue with this lab.
Task 1: Configure the Switch
Configure the hostnames and passwords, as well as the management VLAN 1 settings for the switch, as
indicated in Table 8-3. If you have problems while performing this configuration, refer to Lab 6-2, “Basic
Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Which ports belong to the default VLAN? All
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0

1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 5: Create and Name Two VLANs
Enter the following commands to create two named VLANs:
Switch_A#vlan database
Switch_A(vlan)#vlan 2 name VLAN2
Switch_A(vlan)#vlan 3 name VLAN3
Switch_A(config)#exit
1900:
Switch_A#configure terminal
Switch_A(config)#vlan 2 name VLAN2
Switch_A(config)#vlan 3 name VLAN3
Task 6: Assign Ports to VLAN 2
Assigning ports to VLANs must be done from the interface mode. Enter the following commands to add
ports 4, 5, and 6 to VLAN 2:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config)#interface fastethernet 0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config)#interface fastethernet 0/6
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 2
Switch_A(config-if)#end
1900:
Switch_A#configure terminal
Switch_A(config)#interface Ethernet 0/4
Switch_A(config-if)#vlan static 2
Switch_A(config-if)#interface Ethernet 0/5
Switch_A(config-if)#vlan static 2
Switch_A(config-if)#interface Ethernet 0/6
Switch_A(config-if)#vlan static 2
Switch_A(config)#end
Chapter 8: Virtual LANs 365

366 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 7: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 4 through 6 assigned to VLAN 2? Yes
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/7
Fa0/8, Fa0/9, Fa0/10, Fa0/11
Fa0/12, Fa0/13, Fa0/14, Fa0/15
Fa0/16, Fa0/17, Fa0/18, Fa0/19
Fa0/20, Fa0/21, Fa0/22, Fa0/23
Fa0/24
2 VLAN2 active Fa0/4, Fa0/5, Fa0/6
3 VLAN3 active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- ————————————————————-
Task 8: Assign Ports to VLAN 3
Enter the following commands to assign ports to VLAN 3:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/7
Switch_A(config-if)#switchport mode access

Switch_A(config-if)#switchport access vlan 3
Switch_A(config)#interface fastethernet 0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config)#interface fastethernet 0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 3
Switch_A(config-if)#end
Task 9: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 7 through 9 assigned to VLAN 3? Yes
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24
2 VLAN2 active Fa0/4, Fa0/5, Fa0/6
3 VLAN3 active Fa0/7, Fa0/8, Fa0/9
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
Chapter 8: Virtual LANs 367
———————————————————————————————————————

368 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 10: Test the VLANs
Step 1. Ping from the host in port 0/4 to the host in port 0/1.
Was the ping successful? No
Why?
The ports have different VLAN membership.
Step 2. Ping from the host in port 0/1 to the host in port 0/4.
Was the ping successful? No
Why?
The ports have different VLAN membership.
Step 3. Ping from the host in port 0/4 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The ports have different VLAN membership.
Step 4. Ping from the host in port 0/1 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
The ports are on the same VLAN.
Task 11: Delete a Host from a VLAN
To remove a host from a VLAN, use the no form of the switchport commands in port interface configuration
mode.
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#no switchport mode access
Switch_A(config-if)#no switchport access vlan 2
1900:
Switch_A#config t
Switch_A(config)#interface Ethernet 0/4
Switch_A(config-if)#no vlan static 2
Switch_A(config-if)#end
Task 12: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Is port 0/4 removed from VLAN 2? Yes

Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24
2 VLAN2 active Fa0/5, Fa0/6
3 VLAN3 active Fa0/7, Fa0/8, Fa0/9
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 13: Delete a VLAN
To remove an entire VLAN, enter the VLAN database mode and use the negative form of the command.
Switch_A#vlan database
Switch_A(vlan)#no vlan 3
Deleting VLAN 3...
Switch_A(vlan)#exit
1900:
Switch_A#config t
Switch_A(config)#no vlan 3
Switch_A(config)#exit
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370 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 14: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Is VLAN 3 removed? Yes
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/10
Fa0/11, Fa0/12, Fa0/13, Fa0/14
Fa0/15, Fa0/16, Fa0/17, Fa0/18
Fa0/19, Fa0/20, Fa0/21, Fa0/22
Fa0/23, Fa0/24
2 VLAN2 active Fa0/5, Fa0/6
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
2 enet 100002 1500 - - - - - 0 0
3 enet 100003 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
What happened to the ports that were released from the VLANs?
They are not assigned to a VLAN.
Task 15: Delete VLAN 1
Try to delete VLAN 1, which is the default VLAN, the same way that you deleted VLAN 3.
Switch_A#vlan database
Switch_A(vlan)#no vlan 1

A default VLAN may not be deleted.
Switch_A(vlan)#exit
1900:
Switch_A#config t
Switch_A(config)#no vlan 1
Switch_A(config)#no vlan 1
^
% Invalid input detected at ‘^’ marker.
Switch_A(config)#exit
Can the default VLAN be deleted? No
After you complete the previous step, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.
Challenge Lab 8-4: Static VLANs, STP, and Port Security
Figure 8-5 Static VLANs, STP, and Port Security
Objectives
■ Create and assign VLANs.
■ Configure root bridges for STP.
■ Configure port security.
Equipment
VLAN 1 10.1.0.0/16
VLAN 10 10.10.0.0/16
VLAN 20 10.20.0.0/16
VLAN 30 10.30.0.0/16
VLAN 10
fa0/4–8
The topology shown in Figure 8-5 is using 2950 switches.
NetLab Compatibility Notes
VLAN 1: 10.1.0.2
DefGate: 10.1.0.1
SWA
VLAN 20
fa0/9–16
This lab is fully compatible with a standard NetLab Basic Switch Pod although you will not be able to
fully test your VLANs or port security.
Task 1: Cable the Topology and Basic Configuration
fa0/2
fa0/3
VLAN 30
fa0/17–24
VLAN 10
fa0/4–8
Chapter 8: Virtual LANs 371
VLAN 1: 10.1.0.3
DefGate: 10.1.0.1
fa0/2
SWB
fa0/3
VLAN 20
fa0/9–16
VLAN 30
fa0/17–24
Step 1. Choose two 2950 switches and cable them according to the topology. (If using NetLab, choose
a Basic Switch Pod. Portions of this lab will not be verifiable.)

372 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 2. Configure the switches according to your instructor’s required basic configurations, including
hostnames, passwords, host tables, banner, and lines. Configure each of the switches with the
correct VLAN 1 IP addresses and the correct default gateway.
Step 3. Verify connectivity between SWA and SWB. Pings should be successful. If not, troubleshoot.
Note: Switches should not be able to ping the router yet.
Task 2: Configure VLANs
Step 1. Configure the following VLANs on both SWA and SWB:
■ VLAN 10 is the Accounting VLAN
■ VLAN 20 is the Marketing VLAN
■ VLAN 30 is the Purchasing VLAN
Step 2. Configure the appropriate ports on SWA and SWB for trunking with the switchport mode
trunk command. Verify trunking is properly configured with the show interface trunk command
on both SWA and SWB.
SWA#show interface trunk
Port Mode Encapsulation Status Native vlan
Fa0/2 on 802.1q trunking 1
Fa0/3 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/2 1-4094
Fa0/3 1-4094
Port Vlans allowed and active in management domain
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Port Vlans in spanning tree forwarding state and not pruned
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Step 3. The Fa0/1 port is unused on both SWA and SWB. For enhanced security, administratively shut
down this port. Otherwise, the port will activate whenever it detects a device on the other end.
Step 4. Configure access mode on the rest of the ports using the switchport mode access command.
Assign the access ports to their correct VLAN as specified in the topology.
Step 5. Verify the VLAN configuration on both switches with the show vlan brief command. Your output
should look similar to the following output:
SWA#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11,
Fa0/12
Fa0/13, Fa0/14, Fa0/15,
Fa0/16

30 Purchasing active Fa0/17, Fa0/18, Fa0/19,
Fa0/20
Fa0/21, Fa0/22, Fa0/23,
Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Task 3: Configure the Root Bridge for STP
Step 1. For VLANs 1, 10, and 30, SWA should always be the root bridge. Configure SWA with a spanning-tree
priority of 4096 for these three VLANs.
For VLAN 20, SWA is to never be the root bridge. Configure SWA with a spanning-tree priority
of 61,440.
What is the default priority?
32768
Why would you want to configure some VLANs with a different STP root bridge?
By using different spanning-tree instances for different VLANs, redundant trunk ports can be
used for forwarding traffic for some VLANs while blocking for others.
Step 2. Verify SWA is the root with the show spanning-tree summary command. SWA should be listed
as the root bridge, as shown in the following output below:
SWA#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0001, VLAN0010, VLAN0030
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Chapter 8: Virtual LANs 373
Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 0 0 0 3 3
VLAN0010 0 0 0 3 3
VLAN0020 1 0 0 2 3
VLAN0030 0 0 0 3 3
——————————— ———— ————- ———— ————— —————
4 vlans 1 0 0 11 12
SWB#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0020
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default

374 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 1 0 0 1 2
VLAN0010 1 0 0 1 2
VLAN0020 0 0 1 1 2
VLAN0030 1 0 0 1 2
——————————— ———— ————- ———— ————— —————
4 vlans 3 0 1 4 8
Task 4: Configure Port Security
Step 1. Configure the access ports (Fa0/4 through 24) for access mode and turn on port security.
Step 2. Enter the command to make the first MAC address learned “stick” to the port. No other MAC
addresses should be allowed (maximum of one MAC per port).
Step 3. Enter the command that will automatically shut down the port if a security violation occurs.
Step 4. Verify port security with the show port-security command. Your output should look similar to
the following output:
SWA#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security
Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 0 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 0 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-

Total Addresses in System : 0
Max Addresses limit in System : 1024
Task 5: Verify VLANs and Port Security
Step 1. Test the VLAN configuration by verifying that a host attached to VLAN 10 cannot ping the
hosts of VLAN 20 or VLAN 30.
Step 2. Test the port security configuration by disconnecting a host from a port and connecting a different
host to the same port. The port should automatically shut down. How do you, as the
administrator, re-enable the port?
First, reset port security with the clear port-security sticky command. Second, administratively
disable the port with the shutdown command. Third, reactivate the port with the no shutdown
command. The new MAC address will now stick to the configuration.
SWA !—————————————————
!VLAN configurations do not show
!—————————————————
vlan 10
name Accounting
vlan 20
name Marketing
vlan 30
name Purchasing
!—————————————————
!
hostname SWA
!
enable secret class
!
no ip domain-lookup
ip host SWB 10.1.0.3
!
interface FastEthernet0/1
!
shutdown
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk
interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
Chapter 8: Virtual LANs 375

376 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 10.1.0.2 255.255.0.0
no shutdown
ip default-gateway 10.1.0.1
!
banner motd $
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
exec-timeout 0 0
password cisco
logging synchronous
login

!
end
SWB !—————————————————
!VLAN configurations do not show
!—————————————————
vlan 10
name Accounting
vlan 20
name Marketing
vlan 30
name Purchasing
!—————————————————
!
hostname SWB
!
enable secret class
!
no ip domain-lookup
ip host SWA 10.1.0.2
!
interface FastEthernet0/1
!
shutdown
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk
interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
switchport port-security maximum 1
Chapter 8: Virtual LANs 377

378 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 10.1.0.3 255.255.0.0
no shutdown
ip default-gateway 10.1.0.1
!
banner motd $
***********************************
!!!AUTHORIZED ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
!
exec-timeout 0 0
password cisco
logging synchronous
login
end

CHAPTER 9
VLAN Trunking Protocol
The Study Guide portion of this chapter uses a combination of fill in the blank, open-ended question, and
unique custom exercises to test your knowledge on the theory of VLAN Trunking Protocol.
The Lab Exercises portion of this chapter includes all of the online curriculum labs as well as a comprehensive
lab and a challenge lab to ensure that you have mastered the practical, hands-on skills needed
about VTP.

380 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Study Guide
Trunking
For the purposes of this chapter, a trunk is a physical and logical connection between two switches across
which network traffic travels. In a switched network, a trunk is a point-to-point link that supports several
VLANs. The purpose of a trunk is to conserve ports when a link between two devices that implement
VLANs is created.
In this section, you work through exercises that review trunking, the concept of frame tagging, and basic
trunk configuration.
Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
Two switches directly connected can send and receive traffic for multiple VLANs across a trunk link. The
term trunk originated in the telephone industry to describe a link used to carry multiple conversations. In
switching technologies, you need to identify which VLAN a frame belongs to. To make this identification
possible, switches can use one of two major methods of frame tagging: Inter-Switch Link (ISL), a Cisco
proprietary protocol that used to be the most common, and IEEE 802.1q, which is now the standard for
frame tagging. Newer Cisco IOS Software Releases do not even support ISL anymore. It is important to
understand that a trunk link does not belong to a specific VLAN. A trunk link is a conduit for VLANs
between switches and routers.
With ISL, an Ethernet frame is encapsulated with an additional header that contains a VLAN ID. With
IEEE 802.1q, a tag containing the VLAN ID is embedded into the Ethernet frame.
A port can be configured as a trunk port, an access port, or a dynamic port. Trunk links should be manually
configured, although the Cisco IOS will, by default, detect a trunk link because all ports are set to
dynamic desirable. Record the command, including correct prompt, to configure a port for trunking.
Switch(config-if)#switchport mode trunk
For the 1900 series switches and the 2950 series switches, you do not have to configure the encapsulation
type on a trunk link. However, if you are using a 2900 series switch, which supports both ISL and IEEE
802.1q, then you have to configure the encapsulation type. Record the command, including correct prompt,
to configure a port to use ISL encapsulation.
Switch(config-if)#switchport trunk encapsulation isl
Note: If you are not sure about this command, check Curriculum Lab 9-1, “Trunking with ISL (9.1.5a).”
Now record the command, including correct prompt, to configure a port to use IEEE 802.1q encapsulation.
Switch(config-if)#switchport trunk encapsulation dot1q
If your switch is a 2950 series, you do not configure the encapsulation type. The command is not even
available. However, when configuring a router with a VLAN trunk to a switch, you must specify the
encapsulation type because the router IOS does not auto-detect it. These commands are reviewed later in
the chapter, in the section, “Inter-VLAN Routing Overview.”

Chapter 9: VLAN Trunking Protocol 381
To quickly verify trunking, you can use the show interface trunk command to display output similar to the
following:
Port Mode Encapsulation Status Native vlan
Fa0/1 on 802.1q trunking 1
Fa0/2 on 802.1q trunking 1
Fa0/3 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/1 1-4094
Fa0/2 1-4094
Fa0/3 1-4094
Port Vlans allowed and active in management domain
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Port Vlans in spanning tree forwarding state and not pruned
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,30
You can also view more specific information about a port by using the show interface fa0/1 switchport
command to display output similar to the following:
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Protected: false
Voice VLAN: none (Inactive)
Appliance trust: none

382 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Basic Trunk Configuration Exercise
Use Figure 9-1 to answer the following configuration scenario questions.
Figure 9-1 Basic Trunk Configuration
SWA and SWB are both 1900 switches. Record the command or commands, including prompt, needed to
set the Fa0/2 and Fa0/3 interfaces to trunking. If necessary, specify ISL as the encapsulation. You may
need to research the answer for this question. Try your favorite search engine or Cisco.com.
Switch(config)#interface fa 0/2
Switch(config-if)#trunk on
Switch(config)#interface fa 0/3
Switch(config-if)#trunk on
!Trunk configuration is always ISL so no configuration needed
SWA and SWB are both 2900 switches. Record the command or commands, including prompt, needed to
set the Fa0/2 and Fa0/3 interfaces to trunking. If necessary, specify ISL as the encapsulation.
Switch(config)#interface fa 0/2
Switch(config-if)#switchport mode trunk
Switch(config-if)#switchport trunk encapsulation isl
Switch(config)#interface fa 0/3
Switch(config-if)#switchport mode trunk
Switch(config-if)#switchport trunk encapsulation isl
SWA and SWB are both 2950 switches. Record the command or commands, including prompt, needed to
set the Fa0/2 and Fa0/3 interfaces to trunking. If necessary, specify IEEE 802.1q as the encapsulation.
VTP
000e.385d.e380
Priority: Default
SWA
Switch(config)#interface fa 0/2
Switch(config-if)#switchport mode trunk
Switch(config)#interface fa 0/3
fa0/2
fa0/3
Switch(config-if)#switchport mode trunk
!Trunk configuration is always IEEE 802.1q so no configuration needed
Which switch is the STP root bridge and why?
000d.6562.e380
Priority: Default
SWB is the STP root bridge, because it has the lowest MAC address.
VTP was created by Cisco to solve operational problems in a switched network with VLANs. It is a Cisco
proprietary protocol. With VTP, VLAN configuration is consistently maintained across a common administrative
domain. Additionally, VTP reduces management and monitoring complexities of networks with
VLANs.
In this section, you will work through exercises that cover the basic concepts and configurations of VTP.
You will also find several concept questions to answer. A lesson from Cisco.com will round out your study
of VTP.
fa0/2
fa0/3
SWB

Vocabulary Exercise: Completion
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
The role of VLAN Trunking Protocol, or VTP, is to maintain VLAN configuration consistency across a
common network administration domain. Although switch ports are normally assigned to only a single
VLAN, trunk ports by default carry frames from all VLANs.
Switches can operate in one of three VTP modes. The default mode is VTP server. A switch operating in
VTP server mode propagates configuration changes as VTP messages across trunk links to all connected
switches in the network. Switches that are in VTP client mode and share the same domain name and password
as the server use VTP messages to adjust the local VLAN database. Switches that are in VTP transparent
mode do not use VTP messages. However, a switch in this mode forwards the VTP messages out all
trunk links except for the link the messages were originally received on. In addition, a switch in transparent
mode can create, modify, and delete its own local VLANs. Provide the missing information in Table 9-1.
Table 9-1 VTP Mode Comparisons
Feature Server Mode Client Mode Transparent Mode
Source VTP messages Yes Yes No
Listen to VTP messages Yes Yes No
Create VLANs Yes No Yes 1
Remember VLANs Yes No Yes 1
1. Locally significant only.
Before the VTP server will propagate VTP messages, it must be configured with a VTP domain name. The
default name is null. Because all switches are in VTP server mode by default, there must be a method to
determine which VLAN database will have priority. This is done through the concept of a configuration
revision number, which is 0 when the switch first boots. Each time a VLAN is added, deleted, or modified
by the VTP server, the configuration revision number is incremented and a VTP message is sent out all
trunk ports. If more than one VTP server exists in the same VTP domain, then messages from the server
with the highest configuration revision number take precedence over all other messages. As a precaution
against misconfigurations, it is always a good idea to configure both VTP servers and VTP clients with a
VTP password.
VTP Basic Configuration Exercise
Use Figure 9-2 to answer the following configuration scenario questions.
Figure 9-2 VTP Basic Configuration
You want to configure local VLANs on SWB that will not be propagated to SWA or SWC. In addition,
you do not want SWB to apply any VLANs created by SWA or SWC. Therefore, you need to configure
SWB to be in VTP transparent mode. Record the commands, including prompt, to configure SWB in this
mode.
Switch#vlan database
Switch(vlan)#vtp transparent
!or
SWA
Domain: CCNA3
Server Transparent
SWB
Chapter 9: VLAN Trunking Protocol 383
SWC
Client

384 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Switch#config t
Switch(config)#vtp mode transparent
All your domain-wide VLANs are going to be created on SWA and propagated throughout the domain.
Therefore, you need to configure SWA to be in VTP server mode. Record the commands, including
prompt, to configure SWA in this mode.
Switch#vlan database
Switch(vlan)#vtp server
!or
Switch#config t
Switch(config)#vtp mode server
You do not want SWC to inadvertently be able to create VLANs. Therefore, you need to configure SWC
to be in VTP client mode. Record the commands, including prompt, to configure SWC in this mode.
Switch#vlan database
Switch(vlan)#vtp client
!or
Switch#config t
Switch(config)#vtp mode client
Are there any problems with your configuration? Will SWC update its VLANs when SWA makes VLAN
changes? Explain any problems and how to fix them.
You need to make sure that SWC has a lower configuration revision number than SWA or it will disregard
any VTP messages sent by SWA. You can verify that SWC has a lower revision number by using the show
vtp status command on both switches. However, it is best to delete the VLAN database and then reload the
switch:
SWC#delete flash:vlan.dat
Because SWB is in transparent mode, SWC will receive all VTP messages from SWA. However, no
VLAN updates will occur until the domain name has been specified on switches wishing to participate in
the domain. The following command needs to be entered on both SWA and SWC:
Switch#vlan database
Switch(vlan)#vtp domain CCNA3
!or
Switch#config t
Switch(config)#vtp domain CCNA3
Concept Questions
Explain why VTP was developed by Cisco to solve operational problems in a switched network with
VLANs.
With VTP, VLAN configuration consistency is maintained across a common administration domain.
Additionally, VTP reduces the complexity of managing and monitoring VLAN networks. A network engineer
can make changes on a central switch and have those changes automatically communicated to all
other switches in the same domain.
List the two main types of VTP advertisements.
Requests from clients that want information at bootup and responses from servers are the two main types
of VTP advertisements.

List and describe the three types of VTP messages.
■ Advertisement requests—Clients request VLAN information and the server responds with summary
and subset advertisements.
■ Summary advertisements—Sent by clients and servers every 5 minutes. If the switch receives a revision
number that is higher than the current revision number in that switch, it issues an advertisement
request for new VLAN information.
■ Subset advertisements—Detailed information about VLANs such as VTP version type, domain name
and related fields, and the configuration revision number.
List at least three actions that can trigger a server to send subset advertisements.
■ Create a VLAN
■ Delete a VLAN
■ Suspend a VLAN
■ Change the name of a VLAN
■ Change the MTU of a VLAN
Internet Research: VTP
At Cisco.com, you will find a very thorough review of VTP including information not covered in this
chapter. Use the following link to access this VTP lesson online:
http://www.cisco.com/warp/public/473/vtp_flash/
When you are done, answer the questions that follow.
Introduction to VTP
VTP is a Layer 2 messaging protocol used to maintain VLAN configuration consistency by managing the
addition, deletion, and renaming of VLANs on a network-wide basis.
In a network with six switches and VLANs that are shared across switches, what would you have to do if
you did not use VTP?
Manually configure and maintain the VLANs on every switch.
A VTP frame consists of a VTP header and a VTP message type. The VTP information is inserted in the
data portion of an Ethernet frame.
What kind of address do VTP messages use?
VTP messages use a reserved multicast address.
How often are summary advertisements sent and what is their purpose?
Summary advertisements are sent every 5 minutes by servers and clients to inform other switches in the
domain of what they believe the current configuration revision number to be. They are also sent when a
configuration change is made.
What does an advertisement request cause to happen?
Chapter 9: VLAN Trunking Protocol 385
An advertisement request causes the server to send both a summary and subset advertisements.

386 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
VTP Domain and VTP Modes
When a switch has been cleared and rebooted, it has the following VTP configuration:
■ VTP Domain Name = null
■ VTP Mode = Server
■ Configuration Revision = 0
■ VLANs = 1
The VTP server can add, delete, or rename VLANs. It also advertises the domain name, VLAN configuration,
and configuration revision number to all other switches in the VTP domain. It also maintains a list of
all VLANs in NVRAM so that it can retrieve this information if the switch is reset.
A VTP client cannot add, delete, or rename VLANs. It does not store VLANs in NVRAM.
Switches in VTP transparent mode must have their VLANs configured manually. They do not participate
in VTP or advertise their VLAN configuration. When is it useful to configure a switch in this mode?
When you want to manually configure VLANs or when VLANs are only locally significant and do not
span the rest of the network.
Before VLANs will be advertised by the VTP server, you must configure a domain name.
Assume that VLANs 10, 20, and 30 have been added to a VTP server with appropriate names. What is the
configuration revision number? 3
Now assume that the name for VLAN 10 is changed, VLAN 30 is deleted, and VLAN 40 is added. What is
the configuration revision number? 6
List the three types of trunk links that VTP messages will be sent across.
ISL, 802.1q, and LANE trunks
What MAC address are VTP messages sent to?
Multicast MAC 01-00-0C-CC-CC-CC
Assume that you configure six VLANs on a VTP transparent switch. What would be the configuration
revision number? 0
The configuration revision number is not incremented in transparent mode.
It what situations will a VTP transparent switch forward VTP messages to other switches.
When it is configured in the same domain as the server or when it is configured in the null domain.
Common VTP Issues
Assuming that a new switch was configured with the correct domain name, what would happen if you
were to add a VTP client or server switch with a higher configuration revision number to the network?
As soon as a trunk link is established with the new switch, it will send out a summary advertisement. The
other switches in the network will note the higher configuration revision number and send advertisement
requests to the new switch. The new switch will then send out summary and subset advertisements with
the VLAN configuration. All other switches will delete any existing VLAN configuration and update their
VLANs with the VLANs advertised by the new switch. They will also update their configuration revision
number. This scenario will occur regardless of whether the new switch is in client or server mode.

List three possible ways to reset the configuration revision number on a switch. (Only two methods are
discussed in the presentation. Can you think of another way?)
The quickest way to reset a configuration revision number is to temporarily set the VTP mode to transparent.
You could also temporarily change the domain name. A third way is to delete the vlan.dat file and
reload the switch.
Internet Research: VTP Pruning
There will be a lot of traffic on a large switched network with VLANs that span multiple switches. VTP
pruning is a method of reducing traffic. Research VTP pruning and briefly describe what it is, how it operates,
and what configuration commands, if any, you would use. Make sure to list your sources.
If the student simply enters “vtp pruning” in the Google search engine, one of the first links should be
Cisco.com. Encourage students to use the Cisco.com explanation as their primary source of information,
especially when learning about a Cisco proprietary technology like VTP. However, also encourage them to
explore third-party explanations that might come at a difficult topic from a different perspective.
The following link provides the Cisco.com discussion of VTP pruning:
http://www.cisco.com/univercd/cc/td/doc/product/lan/cat5000/rel_4_2/config/vlans.htm
The following links are helpful third-party sources:
http://www.certificationzone.com/cisco/newsletter/SL/nla_11-30-04_newage.html
http://www.firewall.cx/vlans-vtp-pruning.php
http://www.networknewz.com/2004/0317.html
Inter-VLAN Routing Overview
Inter-VLAN communication cannot occur without a Layer 3 device, such as a router. You will use ISL or
IEEE 802.1q to enable trunking on a router subinterface. In this section, you will briefly review the concept
of inter-VLAN routing. Then, you will work through a inter-VLAN routing configuration exercise.
Vocabulary Exercise: Completion
Chapter 9: VLAN Trunking Protocol 387
Directions: Complete the paragraphs that follow by filling in appropriate words and phrases.
Inter-VLAN communication crosses broadcast domains. When a host in one broadcast domain wishes to
communicate with a host in another broadcast domain, you must use a router. When connecting a router to
a switched network with multiple VLANs, one interface is needed per VLAN because each is on its own
logical network or subnet. You can reduce the number of physical interfaces needed to route VLANs by
using a trunk link between the switch and router. You achieve logical division of a physical interface by
implementing subinterfaces. One subinterface would be configured per VLAN. Each subinterface would
also be configured with an IP address from a separate logical subnet.

388 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Basic Inter-VLAN Configuration Exercise
Use Figure 9-3 to answer the following configuration scenario questions.
Figure 9-3 Basic Inter-VLAN Configuration
What does a router like RTA require in order to route between VLANs?
It requires a Fast Ethernet interface and an IOS that supports inter-VLAN routing.
Record the commands, including prompt, to configure RTA to route for all the VLANs shown in Figure 9-
3. Use IEEE 802.1q encapsulation. Describe all interfaces and make sure you append the word native to
the end of the encapsulation configuration for VLAN 1. Use the first available IP address in each network.
RTA(config)#interface FastEthernet 0
! Activate the physical interface if it won’t come up
RTA(config-if)#no shutdown
VLAN 1 192.168.1.0/24
VLAN 100 192.168.100.0/24
VLAN 200 192.168.200.0/24
VLAN 300 192.168.300.0/24
! Configure the Management VLAN 1. Don’t forget ‘native’
RTA(config-if)#interface FastEthernet 0.1
RTA(config-subif)#description Management VLAN 1
RTA(config-subif)#encapsulation dot1Q 1 native
RTA(config-subif)#ip address 192.168.1.1 255.255.255.0
! Configure routing for VLAN 100
RTA(config-subif)#interface FastEthernet0.100
RTA(config-subif)#description Accounting VLAN 100
RTA(config-subif)#encapsulation dot1Q 100
RTA(config-subif)#ip address 192.168.100.1 255.255.255.0
! Configure routing for VLAN 200
RTA(config-subif)#interface FastEthernet0.200
RTA(config-subif)#description Marketing VLAN 200
RTA(config-subif)#encapsulation dot1Q 200
RTA(config-subif)#ip address 192.168.200.1 255.255.255.0
! Configure routing for VLAN 300
VLAN 100
Accounting
RTA(config-subif)#interface FastEthernet0.300
RTA(config-subif)#description Purchasing VLAN 300
RTA(config-subif)#encapsulation dot1Q 300
RTA
fa0
SWA
VLAN 200
Marketing
RTA(config-subif)#ip address 192.168.300.1 255.255.255.0
VLAN 300
Purchasing

Lab Exercises
Command Reference
In the table that follows, record the command, including the correct switch prompt, that fits the description
for a 1900 Catalyst switch.
1900 Switch Command Description
Switch(config)#interface fa 0/26
Switch(config-if)#trunk on Turns port to trunking mode
Switch#show trunk A Displays trunking information about port 0/26, which is
trunk A
Switch(config)#vtp client Changes the switch to client mode
Switch(config)#vtp server Changes the switch to server mode
Switch(config)#vtp transparent Changes the switch to transparent mode
Switch(config)#vtp domain CCNA3 Sets the name of the VTP management domain to CCNA3
Switch(config)#vtp password cisco Set the VTP password to cisco
Switch#show vtp Displays all VTP information
In the table that follows, record the command, including the correct switch prompt, that fits the description
for a 2900 Catalyst switch. When appropriate, use VLAN database configuration mode.
2900 Switch Command Description
Switch(config)#interface fa 0/1
Switch(config-if)#switchport mode trunk Turns port to trunking mode
Switch(config-if)#switchport trunk encapsulation isl Sets encapsulation type to ISL
Switch(config-if)#switchport trunk encapsulation dot1q Sets encapsulation type to Dot1Q—
the default encapsulation type
Switch#vlan database Enters VLAN database mode
Switch(vlan)#vtp client Changes the switch to client mode
Switch(vlan)#vtp server Changes the switch to server mode
Switch(vlan)#vtp transparent Changes the switch to transparent mode
Switch(vlan)#vtp domain CCNA3 Sets the name of the VTP management
domain to CCNA3
Switch(vlan)#vtp password cisco Set the VTP password to cisco
Switch(vlan)#vtp v2-mode Sets VTP mode to version 2
Switch(vlan)#vtp pruning Enables VTP pruning
Chapter 9: VLAN Trunking Protocol 389
Switch(vlan)#exit Applies the VLAN database changes and
exits the mode

390 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
In the table that follows, record the command, including the correct switch prompt, that fits the description
for a 2950 Catalyst switch. When appropriate, use global configuration mode. Do not use VLAN database
configuration mode.
2950 Switch Command Description
Switch(config)#interface fa 0/1
Switch(config-if)#switchport mode trunk Turns port to trunking mode
Switch#show int fa 0/1 switchport Shows the status of interface Fa0/1, including trunking
information (works with both 2900 and 2950 switches)
Switch(config)#vtp mode client Changes the switch to client mode
Switch(config)#vtp mode server Changes the switch to server mode
Switch(config)#vtp mode transparent Changes the switch to transparent mode
Switch(config)#vtp domain CCNA3 Sets the name of the VTP management domain to CCNA3
Switch(config)#vtp password cisco Set the VTP password to cisco
Switch(config)#vtp v2-mode Sets VTP mode to version 2
Switch(config)#vtp pruning Enables VTP pruning
Switch#show vtp status Displays VTP domain status (works with both 2900 and
2950 switches)
Switch#show vtp counters Displays VTP statistics (works with both 2900 and 2950
switches)
In the table that follows, record the command, including the correct router prompt, that fits the description
for a 2600 series router.
2600 Command Description
Router(config)#int fa0/0 Enters interface mode for interface Fa0/0
Router(config-if)#no shutdown Turns on the interface
Router(config-if)#int fa 0/0.1 Creates subinterface 0/0.1
Router(config-subif)#encapsulation dot1q 1 native Assigns the native VLAN to this logical
subinterface using Dot1Q encapsulation
Router(config-subif)#ip address 192.168.1.1 255.255.255.0 Assigns the IP address 192.168.1.1/24 to
this logical interface
Router(config-subif)#int fa0/0.10 Creates subinterface 0/0.10
Router(config-subif)#encapsulation dot1q 10 Assigns VLAN 10 to this logical interface
using Dot1Q encapsulation
Router(config-subif)#ip address 192.168.10.1 255.255.255.0 Assigns the IP address 192.168.10.1/24 to
this logical interface

Curriculum Lab 9-1: Trunking with ISL (9.1.5a)
Figure 9-4 Topology for Lab 9-1
Table 9-2 Lab Equipment Configuration
Switch Switch Name VLAN 1 IP Address VLAN Names Switch Port
Designation and Numbers Assignments
Switch 1 Switch_A 192.168.1.2 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
Switch 2 Switch_B 192.168.1.3 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both routers is 255.255.255.0.
Objectives
FA0/1 FA0/1
FA0/12 Trunk 802.1q
FA0/12
Switch 1 Switch 2
Straight-Through Cable
Crossover Cable
Rollover (Console) Cable
Serial Cable
■ Create a basic switch configuration and verify it.
■ Create multiple VLANs, name them, and assign multiple member ports to them.
Chapter 9: VLAN Trunking Protocol 391
■ Create an ISL trunk line between the two switches to allow communication between paired VLANs.
■ Test the VLANs’ functionality by moving a workstation from one VLAN to another.

392 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Background/Preparation
Important Note: The use of Catalyst 2950 switches is not appropriate for this lab, because those switches support
only 802.1q trunking.
Trunking changes the formatting of the packets. The ports need to be in agreement as to which format is
being used to transmit data on the trunk, or no data will be passed. If different trunking encapsulation
occurs on the two ends of the link, they will not able to communicate. A similar situation will occur if one
of your ports is configured in trunking mode (unconditionally) and the other one is in access mode (unconditionally).
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default. This lab will help demonstrate how you can use VLANs to separate traffic and reduce
broadcast domains.
Cable a network that is similar to the one in Figure 9-4. The configuration output used in this lab is produced
from a 2900 switch. Another switch might produce different output. You should execute the following
steps on each switch unless you are specifically instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B, “Erasing and Reloading the Switch,” before you
continue with this lab.
Task 1: Configure the Switch
Configure the hostname, access, and command mode passwords, as well as the management LAN settings.
These values are shown in Table 9-2. If you have problems while performing this configuration, refer to
Lab 6-2, “Basic Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are correctly configured, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16

1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 5: Create and Name Three VLANs
Use the following commands to create three named VLANs:
2900 Switch
Switch_A#vlan database
Switch_A(vlan)#vlan 10 name Accounting
Switch_A(vlan)#vlan 20 name Marketing
Switch_A(vlan)#vlan 30 name Engineering
Switch_A(config)#exit
2950 Switch
Switch_A#configure terminal
Switch_A(config)#vlan 10
Switch_A(config-vlan)#name Accounting
Switch_A(config-vlan)#vlan 20
Switch_A(config-vlan)#name Marketing
Switch_A(config-vlan)#vlan 30
Switch_A(config-vlan)#name Engineering
Note: VLAN database mode is being deprecated in future releases of Cisco IOS. For now, both VLAN database mode
and global configuration mode are supported for creating VLANs.
Task 6: Assign Ports to VLAN 10
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394 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
You must assign ports to VLANs from the interface mode. Enter the following commands to add ports 0/4
to 0/6 to VLAN 10:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/6
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#end
Note: Use the range parameter to quickly configure several interfaces with the same command. For example:
Switch_A#configure terminal
Switch_A(config)#interface range fastethernet 0/4 - 6
Switch_A(config-if-range)#switchport mode access
Switch_A(config-if-range)#switchport access vlan 10
Switch_A(config-if-range)#end
Task 7: Assign Ports to VLAN 20
Enter the following commands to add ports 0/7 to 0/9 to VLAN 20:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/7
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#end
Task 8: Assign Ports to VLAN 30
Enter the following commands to add ports 0/10 to 0/12 to VLAN 30:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/10
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#interface fastethernet 0/11
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30

Switch_A(config-if)#interface fastethernet 0/12
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#end
Task 9: Create VLANs on Switch_B
Repeat Tasks 5 through 8 on Switch_B to create its VLANs.
Task 10: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 0/10 to 0/12 assigned to VLAN 30? Yes
Switch_A#sh vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
30 Engineering active Fa0/10, Fa0/11, Fa0/12
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
30 enet 100030 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
Chapter 9: VLAN Trunking Protocol 395
———————————————————————————————————————

396 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 11: Test the VLANs
Step 1. Ping from the host in Switch_A port 0/12 to the host in Switch_B port 0/12.
Was the ping successful? No
Why?
No trunk has been configured.
Step 2. Ping from the host in Switch_A port 0/12 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces are in different VLANs.
Task 12: Create the ISL Trunk
On both Switch_A and Switch_B, enter the following command at the Fast Ethernet 0/1 interface command
prompt:
Switch_A(config)#interface fastethernet 0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#switchport trunk encapsulation isl
Switch_A(config-if)#end
Switch_B(config)#interface fastethernet 0/1
Switch_B(config-if)#switchport mode trunk
Switch_B(config-if)#switchport trunk encapsulation isl
Switch_B(config-if)#end
Task 13: Verify the ISL Trunk
To verify that port Fast Ethernet 0/1 has been established as a trunk port, enter show interface fastethernet
0/1 switchport at the privileged EXEC mode prompt.
What type of trunking encapsulation is shown in the output? ISL
According to the output with show interface fastethernet 0/1 switchport on Switch_B, is there a difference
between the Administrative Trunking Encapsulation and the Operational Trunking Encapsulation?
Switch_A#show interface fastEthernet 0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: isl
Operational Trunking Encapsulation: isl
Negotiation of Trunking: Disabled
Access Mode VLAN: 0 ((Inactive))

Trunking Native Mode VLAN: 1 (default)
Trunking VLANs Enabled: ALL
Trunking VLANs Active: 1,10,20,30
Pruning VLANs Enabled: 2-1001
Priority for untagged frames: 0
Override vlan tag priority: FALSE
Voice VLAN: none
Appliance trust: none
Self Loopback: No
No, both encapsulation types are ISL.
On the fragment “Trunking VLANs Enable” from the last output, what does the word ALL mean?
It means that traffic from all VLANs is allowed to cross the trunked link.
What would happen if the two ports of the trunk were using different encapsulation?
It would not form a trunk.
Explain.
The encapsulation must match on both sides of the link in order for the trunk to form.
Task 14: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/12 to the host in
Switch_B port 0/12.
Was the ping successful? Yes
Why?
The hosts are on the same VLAN with trunking enabled on port 0/1.
Step 2. Ping from the host in Switch_A port 0/12 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces are on different VLANs.
Task 15: Move the Hosts
Move the host in Switch_A from port 0/12 to port 0/8, wait until the port LED turns green, and then go to
the next task.
Task 16: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/8 to the host in
Switch_B port 0/12.
Was the ping successful? No
Why?
The hosts are on different VLANs.
Step 2. Ping from the host in Switch_A port 0/8 to the switch IP 192.168.1.2.
Chapter 9: VLAN Trunking Protocol 397

398 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Was the ping successful? No
Why?
The hosts are on different VLANs.
Task 17: Move the Hosts
Move the host in Switch_B from port 0/12 to port 0/7, wait until the port LED turns green, and then go to
the next task.
Task 18: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/8 to the host in
Switch_B port 0/7.
Was the ping successful? Yes
Why?
The hosts are now on the same VLAN (VLAN 20).
Step 2. Ping from the host in Switch_A port 0/8 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces are on different VLANs.
Task 19: Move the Hosts
Move the host in Switch_A from port 0/8 to port 0/2, wait until the port LED turns green, and then go to
the next task.
Task 20: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/2 to the host in
Switch_B port 0/7.
Was the ping successful? No
Step 2. Ping from the host in Switch_A port 0/2 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
Both interfaces are assigned to the same VLAN (VLAN 1).
Task 21: Move the Hosts
Move the host in Switch_B from port 0/7 to port 0/3, wait until the port LED turns green, and then go to
the next task.
Task 22: Test the VLANs and the Trunk

Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/2 to the host in
Switch_B port 0/3.
Was the ping successful? Yes
Why?
Both hosts now belong to the same VLAN.
Step 2. Ping from the host in Switch_B port 0/3 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
Both interfaces are assigned to the same VLAN (VLAN 1).
Step 3. Ping from the host in Switch_B port 0/3 to the switch IP 192.168.1.3.
Was the ping successful? Yes
Why?
Both interfaces are assigned to the same VLAN (VLAN 1).
What conclusions can you draw from the testing that you just performed in regard to VLAN
membership and VLANs across a trunk?
Hosts must be grouped together into the same VLAN before they can communicate with each
other. Trunk links carry VLAN traffic across switches.
Step 4. After you complete the previous steps, log off (by typing exit) and turn all the devices off.
Then, remove and store the cables and adapter.
Switch_A
Switch_A#show running-config
Building configuration...
Current configuration:
!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Switch_A
!
enable secret 5 $1$Spup$4rLiyqQseDcu2xWzhd9Ko.
Chapter 9: VLAN Trunking Protocol 399

400 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
ip subnet-zero
!
interface FastEthernet0/1
switchport mode trunk
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
switchport access vlan 10
!
interface FastEthernet0
switchport access vlan 10
!
interface FastEthernet0/6
switchport access vlan 10
!
interface FastEthernet0/7
switchport access vlan 20
!
interface FastEthernet0/8
switchport access vlan 20
!
interface FastEthernet0/9
switchport access vlan 20
!

interface FastEthernet0/10
switchport access vlan 30
!
interface FastEthernet0/11
switchport access vlan 30
!
interface FastEthernet0/12
switchport access vlan 30
!
interface VLAN1
ip address 192.168.1.2 255.255.255.0
no ip directed-broadcast
no ip route-cache
!
ip default-gateway 192.168.1.1
!
line con 0
password cisco
login
transport input none
stopbits 1
line vty 0 4
password cisco
login
line vty 5 15
password cisco
login
!
end
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402 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Curriculum Lab 9-2: Trunking with 802.1q (9.1.5b)
Figure 9-5 Topology for Lab 9-2
Table 9-3 Lab Equipment Configuration
Switch Switch VLAN 1 IP VLAN Names Switch Port
Designation Name Address and Numbers Assignments
Switch 1 Switch_A 192.168.1.2 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
Switch 2 Switch_B 192.168.1.3 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both routers is 255.255.255.0.
Objectives
■ Create a basic switch configuration and verify it.
■ Create multiple VLANs, name them, and assign multiple member ports to them.
■ Create an 802.1q trunk line between the two switches to allow communication between paired VLANs.
■ Test the VLANs’ functionality by moving a workstation from one VLAN to another.
Background/Preparation
FA0/1 FA0/1
FA0/12 Trunk 802.1q
FA0/12
Switch 1 Switch 2
Straight-Through Cable
Rollover (Console) Cable
Crossover Cable
Serial Cable
Trunking changes the formatting of the packets. The ports need to be in agreement as to which format is
being used to transmit data on the trunk, or no data will be passed. If the two ends of the link have a different
trunking encapsulation, they will not be able to communicate. A similar situation will occur if one
of your ports is configured in trunking mode (unconditionally) and the other one is in access mode (unconditionally).
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default. This lab will help demonstrate how you can use VLANs to separate traffic and reduce
broadcast domains.

Cable a network that is similar to the one in Figure 9-5. The configuration output that is used in this lab is
produced from a 2950 series switch. Another switch might produce different output. You should execute
the following steps on each switch unless you are specifically instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname, access, and command mode passwords, as well as the management LAN settings.
These values are shown in Table 9-3. If you have problems while performing this configuration, refer to
Lab 6-2, “Basic Switch Configuration.” Do not configure VLANs and trunking yet.
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are configured correctly, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Chapter 9: VLAN Trunking Protocol 403
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0

404 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 5: Create and Name Three VLANs
Enter the following commands to create three named VLANs:
2900 Switch
Switch_A#vlan database
Switch_A(vlan)#vlan 10 name Accounting
Switch_A(vlan)#vlan 20 name Marketing
Switch_A(vlan)#vlan 30 name Engineering
Switch_A(vlan)#exit
2950 Switch
Switch_A#configure terminal
Switch_A(config)#vlan 10
Switch_A(config-vlan)#name Accounting
Switch_A(config-vlan)#vlan 20
Switch_A(config-vlan)#name Marketing
Switch_A(config-vlan)#vlan 30
Switch_A(config-vlan)#name Engineering
Note: VLAN database mode is being deprecated in future releases of Cisco IOS. For now, both VLAN database mode
and global configuration mode are supported for creating VLANs.
Task 6: Assign Ports to VLAN 10
You must assign ports to VLANs from the interface mode. Enter the following commands to add ports 0/4
to 0/6 to VLAN 10:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/6
Switch_A(config-if)#switchport mode access

Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#end
Note: Use the range parameter to quickly configure several interfaces with the same command. For example:
Switch_A#configure terminal
Switch_A(config)#interface range fastethernet 0/4 - 6
Switch_A(config-if-range)#switchport mode access
Switch_A(config-if-range)#switchport access vlan 10
Switch_A(config-if-range)#end
Task 7: Assign Ports to VLAN 20
Enter the following commands to add ports 0/7 to 0/9 to VLAN 20:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/7
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#end
Task 8: Assign Ports to VLAN 30
Enter the following commands to add ports 0/10 to 0/12 to VLAN 30:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/10
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#interface fastethernet 0/11
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#interface fastethernet 0/12
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#end
Task 9: Create VLANs on Switch_B
Repeat Tasks 5 through 8 on Switch_B to create its VLANs.
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406 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 10: Display the VLAN Interface Information
On both switches, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Are ports 0/10 to 0/12 assigned to VLAN 30? Yes
Switch_A#sh vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
30 Engineering active Fa0/10, Fa0/11, Fa0/12
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
30 enet 100030 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 11: Test the VLANs
Step 1. Ping from the host in Switch_A port 0/12 to the host in Switch_B port 0/12.
Was the ping successful? No

Why?
No trunk has been configured yet.
Step 2. Ping from the host in Switch_A port 0/12 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces are in different VLANs.
Task 12: Create the Trunk
On both switches, Switch_A and Switch_B, enter the following command at the Fast Ethernet 0/1 interface
command prompt. Note that it is not necessary to specify the encapsulation on a 2950, because it only
supports 802.1q.
Switch_A(config)#interface fastethernet 0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#end
Switch_B(config)#interface fastethernet 0/1
Switch_B(config-if)#switchport mode trunk
Switch_B(config-if)#end
2900:
Switch_A(config)#interface fastethernet0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#switchport trunk encapsulation dot1q
Switch_A(config-if)#end
Switch_B(config)#interface fastethernet0/1
Switch_B(config-if)#switchport mode trunk
Switch_B(config-if)#switchport trunk encapsulation dot1q
Switch_B(config-if)#end
Task 13: Verify the Trunk
To verify that port Fast Ethernet 0/1 has been established as a trunk port, enter show interface fastethernet
0/1 switchport at the privileged EXEC mode prompt.
What type of trunking encapsulation is shown on the output results? Dot1q
According to the output with show interface fastethernet 0/1 switchport on Switch_B, is there a difference
between the Administrative Trunking Encapsulation and the Operational Trunking Encapsulation?
Switch_A#show interface fastEthernet 0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Chapter 9: VLAN Trunking Protocol 407

408 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Voice VLAN: none (Inactive)
Appliance trust: none
No, both encapsulation types were Dot1q.
On the fragment “Trunking VLANs Enable” from the last output, what does the word ALL mean?
It means that traffic from all VLANs is allowed to cross the trunk link.
What would happen if the two ports of the trunk were using different encapsulation?
It would not form a trunk.
Explain.
The encapsulation must match on both sides of the link in order for the trunk to form.
Task 14: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/12 to the host in
Switch_B port 0/12.
Was the ping successful? Yes
Why?
Both hosts are in the same VLAN and the trunk has been configured.
Step 2. Ping from the host in Switch_A port 0/12 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces belong to different VLANs.
Task 15: Move the Hosts
Move the host in Switch_A from port 0/12 to port 0/8, wait until the port LED turns green, and then go to
the next task.

Task 16: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/8 to the host in
Switch_B port 0/12.
Was the ping successful? No
Why?
The hosts are on separate VLANs.
Step 2. Ping from the host in Switch_A port 0/8 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces belong to different VLANs.
Task 17: Move the Hosts
Move the host in Switch_B from port 0/12 to port 0/7, wait until the port LED turns green, and then go to
the next task.
Task 18: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/8 to the host in
Switch_B port 0/7.
Was the ping successful? Yes
Why?
The hosts are now on the same VLAN (VLAN 20).
Step 2. Ping from the host in Switch_A port 0/8 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces belong to different VLANs.
Task 19: Move the Hosts
Chapter 9: VLAN Trunking Protocol 409
Move the host in Switch_A from port 0/8 to port 0/2, wait until the port LED turns green, and then go to
the next task.

410 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 20: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/2 to the host in
Switch_B port 0/7.
Was the ping successful? No
Step 2. Ping from the host in Switch_A port 0/2 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
Both interfaces are assigned to the same VLAN (VLAN 1).
Task 21: Move the Hosts
Move the host in Switch_B from port 0/7 to port 0/3, wait until the port LED turns green, and then go to
the next task.
Task 22: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/2 to the host in
Switch_B port 0/3.
Was the ping successful? Yes
Why?
Both hosts now belong to the same VLAN.
Step 2. Ping from the host in Switch_B port 0/3 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Why?
Both hosts now belong to the same VLAN.
Step 3. Ping from the host in Switch_B port 0/3 to the switch IP 192.168.1.3.
Was the ping successful? Yes
Why?
Both interfaces are assigned to the same VLAN (VLAN 1).
What conclusions can you draw from the testing that you just performed in regard to VLAN
membership and VLANs across a trunk?
Hosts must be grouped together into the same VLAN before they can communicate with each
other. Trunk links carry VLAN traffic across switches.
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.

Curriculum Lab 9-3: VTP Client and Server
Configurations (9.2.5)
Figure 9-6 Topology for Lab 9-3
Table 9-4 Lab Equipment Configuration
Switch Switch Name VLAN 1 VLAN Names Switch Port
Designation IP Address and Numbers Assignments
Switch 1 Switch_A 192.168.1.2 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
Switch 2 Switch_B 192.168.1.3 VLAN 1 Native Fa0/2–0/3
VLAN 10 Accounting Fa0/4–0/6
VLAN 20 Marketing Fa0/7–0/9
VLAN 30 Engineering Fa0/10–0/12
The enable secret password for both routers is class.
The enable, VTY, and console password for both routers is cisco.
The subnet mask for both routers is 255.255.255.0.
Objectives
■ Create a basic switch configuration and verify it.
■ Create multiple VLANs, name them, and assign multiple member ports to them.
■ Configure the VTP protocol to establish server and client switches.
■ Create an 802.1q trunk line between the two switches to allow communication between paired
VLANs.
■ Test the VLANs’ functionality by moving a workstation from one VLAN to another.
Background/Preparation
FA0/1 FA0/1
FA0/12 Trunk 802.1q
FA0/12
Switch 1 Switch 2
Straight-Through Cable
Rollover (Console) Cable
Chapter 9: VLAN Trunking Protocol 411
Crossover Cable
Serial Cable
When you are managing a switch, the management domain is always VLAN 1. The network administrator’s
workstation must have access to a port in the VLAN 1 management domain. All ports are assigned to
VLAN 1 by default.

412 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Cable a network that is similar to the one in Figure 9-6. The configuration output used in this lab is produced
from a 2950 series switch. Another switch might produce different output. You should execute the
following steps on each switch unless you are specifically instructed otherwise.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Configure the Switches
Configure the hostname, access, and command mode passwords, as well as the management LAN settings.
These values are shown in Table 9-4. If you have problems while performing this configuration, refer to
Lab 6-2, “Basic Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the host to use the same subnet for addresses, masks, and the default gateway as the switch.
Task 3: Verify Connectivity
To verify that the hosts and switch are configured correctly, ping the switch from the hosts.
Were the pings successful? Yes
If the answer is no, troubleshoot the hosts and switch configurations.
Task 4: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0

1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Task 5: Configure VTP
You need to configure VLAN Trunking Protocol (VTP) on both switches. VTP is the protocol that communicates
information about which VLANs exist from one switch to another. If VTP did not provide this
information, you would have to create VLANs on all switches individually.
By default, the Catalyst switch series are configured as VTP servers. If the server services are turned off,
use the following command to turn it back on.
2900 Switch
Switch_A#vlan database
Switch_A(vlan)#vtp server
Switch_A(vlan)#exit
2950 Switch
Switch_A#configure terminal
Switch_A(config)#vtp mode server
Switch_A(config)#end
Note: VLAN database mode is being deprecated in future releases of Cisco IOS. For now, both VLAN database mode
and global configuration mode are supported for creating VLANs.
Task 6: Create and Name Three VLANs
Enter the following commands to create three named VLANs:
2900 Switch
Switch_A#vlan database
Switch_A(vlan)#vlan 10 name Accounting
Switch_A(vlan)#vlan 20 name Marketing
Switch_A(vlan)#vlan 30 name Engineering
Switch_A(vlan)#exit
2950 Switch
Switch_A#configure terminal
Switch_A(config)#vlan 10
Switch_A(config-vlan)#name Accounting
Switch_A(config-vlan)#vlan 20
Switch_A(config-vlan)#name Marketing
Switch_A(config-vlan)#vlan 30
Switch_A(config-vlan)#name Engineering
Chapter 9: VLAN Trunking Protocol 413

414 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 7: Assign Ports to VLAN 10
You must assign ports to VLANs from the interface mode. Enter the following commands to add ports 0/4
to 0/6 to VLAN 10:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/4
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet 0/6
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#end
Note: Use the range parameter to quickly configure several interfaces with the same command. For example:
Switch_A#configure terminal
Switch_A(config)#interface range fastethernet 0/4 - 6
Switch_A(config-if-range)#switchport mode access
Switch_A(config-if-range)#switchport access vlan 10
Switch_A(config-if-range)#end
Task 8: Assign Ports to VLAN 20
Enter the following commands to add ports 0/7 to 0/9 to VLAN 20:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/7
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet 0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#end
Task 9: Assign Ports to VLAN 30
Enter the following commands to add ports 0/10 to 0/12 to VLAN 30:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet 0/10
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#interface fastethernet 0/11
Switch_A(config-if)#switchport mode access

Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#interface fastethernet 0/12
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 30
Switch_A(config-if)#end
Task 10: Display the VLAN Interface Information
On Switch_A, enter the command show vlan at the privileged EXEC mode prompt.
Switch_A#show vlan
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
30 Engineering active Fa0/10, Fa0/11, Fa0/12
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
30 enet 100030 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Are ports 0/10 to 0/12 assigned to VLAN 30? Yes
Chapter 9: VLAN Trunking Protocol 415

416 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 11: Configure the VTP Client
Configure Switch_B to be a VTP client.
Switch_B#vlan database
Switch_B(vlan)#vtp client
Switch_B(vlan)#vtp domain group1
Switch_B(vlan)#exit
Task 12: Create the Trunk
On both Switch_A and Switch_B, enter the following command at the Fast Ethernet 0/1 interface command
prompt. Note that it is not necessary to specify the encapsulation on a 2950, because it only supports
802.1q.
Switch_A(config)#interface fastethernet 0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#end
Switch_B(config)#interface fastethernet 0/1
Switch_B(config-if)#switchport mode trunk
Switch_B(config-if)#end
2900:
Switch_A(config)#interface fastethernet0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#switchport trunk encapsulation dot1q
Switch_A(config-if)#end
Switch_B(config)#interface fastethernet0/1
Switch_B(config-if)#switchport mode trunk
Switch_B(config-if)#switchport trunk encapsulation dot1q
Switch_B(config-if)#end
Task 13: Verify the Trunk
To verify that port Fast Ethernet 0/1 has been established as a trunk port, enter show interface fastethernet
0/1 switchport at the privileged EXEC mode prompt.
Switch_A#show interface fastEthernet 0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: trunk
Administrative Trunking Encapsulation: dot1q
Operational Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Voice VLAN: none

Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Operational private-vlan: none
Trunking VLANs Enabled: ALL
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL
Protected: false
Voice VLAN: none (Inactive)
Appliance trust: none
What type of trunking encapsulation is shown in the output? Dot1q
Task 14: Display the VLAN Interface Information
On Switch_B, enter the command show vlan at the privileged EXEC mode prompt.
Switch_B#show vlan
Switch_B#show vlan
Chapter 9: VLAN Trunking Protocol 417
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/5, Fa0/6, Fa0/7, Fa0/8
Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
10 Accounting active
20 Marketing active
30 Engineering active
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
30 enet 100030 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0

418 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Do VLANs 10, 20, and 30 show without your having to type them in? Yes
Why did this happen?
Because Switch_A is a VTP server and it sent VLAN information to Switch_B.
Task 15: Assign Ports to VLAN 10
Although the VLAN definitions have migrated to Switch_B by using VTP, you still must assign ports to
these VLANs on Switch_B. You must assign ports to VLANs from the interface mode. Enter the following
commands to add ports 0/4 to 0/6 to VLAN 10:
Switch_B#configure terminal
Switch_B(config)#interface fastethernet 0/4
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 10
Switch_B(config-if)#interface fastethernet 0/5
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 10
Switch_B(config-if)#interface fastethernet 0/6
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 10
Switch_B(config-if)#end
Task 16: Assign Ports to VLAN 20
Enter the following commands to add ports 0/7 to 0/9 to VLAN 20:
Switch_B#configure terminal
Switch_B(config)#interface fastethernet 0/7
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 20
Switch_B(config-if)#interface fastethernet 0/8
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 20
Switch_B(config-if)#interface fastethernet 0/9
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 20
Switch_B(config-if)#end

Task 17: Assign Ports to VLAN 30
Enter the following commands to add ports 0/10 to 0/12 to VLAN 30:
Switch_B#configure terminal
Switch_B(config)#interface fastethernet 0/10
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 30
Switch_B(config-if)#interface fastethernet 0/11
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 30
Switch_B(config-if)#interface fastethernet 0/12
Switch_B(config-if)#switchport mode access
Switch_B(config-if)#switchport access vlan 30
Switch_B(config-if)#end
Task 18: Display the VLAN Interface Information
On Switch_B, enter the command show vlan at the privileged EXEC mode prompt.
Switch_B#show vlan
Switch_B#show vlan
Chapter 9: VLAN Trunking Protocol 419
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
30 Engineering active Fa0/10, Fa0/11, Fa0/12
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———
1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
30 enet 100030 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———

420 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Are ports 0/10 to 0/12 assigned to VLAN 30? Yes
Task 19: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/12 to the host in
Switch_B port 0/12.
Was the ping successful? Yes
Why?
Both hosts are in the same VLAN with the trunk link properly configured.
Step 2. Ping from the host in Switch_A port 0/12 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces belong to different VLANs.
Task 20: Move the Hosts
Move the host in Switch_A from port 0/12 to port 0/8, wait until the port LED turns green, and then go to
the next task.
Task 21: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/8 to the host in
Switch_B port 0/12.
Was the ping successful? No
Why?
The hosts are on separate VLANs.
Step 2. Ping from the host in Switch_A port 0/8 to the switch IP 192.168.1.2.
Was the ping successful? No
Why?
The interfaces belong to different VLANs.
After you complete the previous steps, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.

Curriculum Lab 9-4: Configuring Inter-VLAN Routing
(9.3.6)
Figure 9-7 Topology for Lab 9-4
Table 9-5 Lab Equipment Configuration
Switch Switch Name VLAN 1 VLAN Names Switch Port
Designation IP Address and Numbers Assignments
Switch 1 Switch_A 192.168.1.2 VLAN 1 Native
VLAN 10 Sales
VLAN 20 SupportFa0/1–0/4
Fa0/5–0/8
Fa0/9–0/12
The enable secret password is class.
The enable, VTY, and console password is cisco.
The subnet mask is 255.255.255.0.
Objectives
■ Create a basic switch configuration and verify it.
■ Create multiple VLANs, name them, and assign multiple member ports to them.
■ Create a basic configuration on a router.
■ Create an 802.1q trunk line between the switch and router to allow communication between VLANs.
■ Test the routing functionality.
Background/Preparation
FA0/5
FA0/9
Straight-Through Cable
Rollover (Console) Cable
Chapter 9: VLAN Trunking Protocol 421
Cable a network that is similar to the one in Figure 9-7. The configuration output that is used in this lab is
produced from a 2950 series switch. Another switch might produce different output. You should execute
erase and reload procedures on each switch unless you are specifically instructed otherwise. Instructions
are also provided for the 1900 series switch, which initially displays a User Interface Menu. Select the
FA0/1
Crossover Cable
Serial Cable

422 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Command Line option from the menu to perform the steps for this lab.
Note: The router used must have a Fast Ethernet interface in order to support trunking and inter-VLAN routing. The
2500 series router cannot be used for this lab.
Start a HyperTerminal session.
Implement the procedure documented in Appendix B before you continue with this lab.
Task 1: Configure the Switch
Configure the hostname, access, and command mode passwords, as well as the management LAN settings.
These values are shown in Table 9-5. If you have problems while performing this configuration, refer to
Lab 6-2, “Basic Switch Configuration.”
Task 2: Configure the Hosts Attached to the Switch
Configure the hosts by using the following information.
The host in port 0/5:
IP address: 192.168.5.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.5.1
The host in port 0/9:
IP address: 192.168.7.2
Subnet mask: 255.255.255.0
Default gateway: 192.168.7.1
Task 3: Verify Connectivity
Step 1. Verify that the switch ports and host NIC link lights are lit.
Step 2. Ping the switch IP address from the hosts.
Were the pings successful? No
Why or why not?
The hosts are on different networks.
Task 4: Create and Name Two VLANs
Enter the following commands to create two named VLANs:
Switch_A#vlan database
Switch_A(vlan)#vlan 10 name Sales
Switch_A(vlan)#vlan 20 name Support
Switch_A(vlan)#exit

1900:
Switch_A#config t
Switch_A(config)#vlan 10 name Sales
Switch_A(config)#vlan 20 name Support
Switch_A(config)#exit
Task 5: Assign Ports to VLAN 10
You must assign ports to VLANs from the interface mode. Enter the following commands to add ports 0/5
to 0/8 to VLAN 10:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet0/5
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet0/6
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet0/7
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#interface fastethernet0/8
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 10
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface ethernet 0/5
Switch_A(config-if)#vlan static 10
Switch_A(config-if)#interface ethernet 0/6
Switch_A(config-if)#vlan static 10
Switch_A(config-if)#interface ethernet 0/7
Switch_A(config-if)#vlan static 10
Switch_A(config-if)#interface ethernet 0/8
Switch_A(config-if)#vlan static 10
Switch_A(config-if)#end
Task 6: Assign Ports to VLAN 20
Enter the following commands to add ports 0/9 to 0/12 to VLAN 20:
Switch_A#configure terminal
Switch_A(config)#interface fastethernet0/9
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
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424 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Switch_A(config-if)#interface fastethernet0/10
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet0/11
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#interface fastethernet0/12
Switch_A(config-if)#switchport mode access
Switch_A(config-if)#switchport access vlan 20
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface ethernet 0/9
Switch_A(config-if)#vlan static 20
Switch_A(config-if)#interface ethernet 0/10
Switch_A(config-if)#vlan static 20
Switch_A(config-if)#interface ethernet 0/11
Switch_A(config-if)#vlan static 20
Switch_A(config-if)#interface ethernet 0/12
Switch_A(config-if)#vlan static 20
Switch_A(config-if)#end
Task 7: Display the VLAN Interface Information
On Switch_A, enter the command show VLAN at the privileged EXEC mode prompt.
Switch_A#show vlan
Switch_A#show vlan
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Fa0/2, Fa0/3, Fa0/4
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
10 Sales active Fa0/5, Fa0/6, Fa0/7, Fa0/8
20 Support active Fa0/9, Fa0/10, Fa0/11, Fa0/12
1002 fddi-default act/unsup
1003 token-ring-default act/unsup
1004 fddinet-default act/unsup
1005 trnet-default act/unsup
VLAN Type SAID MTU Parent RingNo BridgeNo Stp BrdgMode Trans1 Trans2
—— ——- ————— ——- ——— ——— ———— —— ———— ——— ———

1 enet 100001 1500 - - - - - 0 0
10 enet 100010 1500 - - - - - 0 0
20 enet 100020 1500 - - - - - 0 0
1002 fddi 101002 1500 - - - - - 0 0
1003 tr 101003 1500 - - - - - 0 0
1004 fdnet 101004 1500 - - - ieee - 0 0
1005 trnet 101005 1500 - - - ibm - 0 0
Remote SPAN VLANs
———————————————————————————————————————
Primary Secondary Type Ports
———- ————- ————————- —————————————————————
Are ports assigned correctly? Yes
Task 8: Create the Trunk
On Switch_A, enter the following command at the Fast Ethernet 0/1 interface command prompt. Note that
Fast Ethernet 0/1 and the other access ports on a 1900 switch only support 10-Mbps Ethernet and cannot
be used as trunk ports. The trunk ports (if present) on a 24-port 1900 are typically Fast Ethernet 0/26 and
0/27.
Switch_A(config)#interface fastethernet0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#end
2900:
Switch_A(config)#interface fastethernet0/1
Switch_A(config-if)#switchport mode trunk
Switch_A(config-if)#switchport trunk encapsulation dot1q
Switch_A(config-if)#end
1900:
Switch_A#config t
Switch_A(config)#interface fastethernet0/26
Switch_A(config-if)#trunk on
Task 9: Configure the Router
Step 1. Configure the router with the following data. Note that, to support trunking and inter-VLAN
routing, the router must have a Fast Ethernet interface.
Hostname: Router_A
Console, VTY, and enable passwords: cisco
Enable secret password: class
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426 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 2. Configure the Fast Ethernet interface by using the following commands:
Note: If working with a 1900 switch, replace the dot1.q encapsulation with isl in the following router configuration
commands.
Router_A(config)#interface fastethernet 0/0
Router_A(config-if)#no shutdown
Router_A(config-if)#interface fastethernet 0/0.1
Router_A(config-subif)#encapsulation dot1q 1
Router_A(config-subif)#ip address 192.168.1.1 255.255.255.0
Router_A(config-if)#interface fastethernet 0/0.2
Router_A(config-subif)#encapsulation dot1q 10
Router_A(config-subif)#ip address 192.168.5.1 255.255.255.0
Router_A(config-if)#interface fastethernet 0/0.3
Router_A(config-subif)#encapsulation dot1q 20
Router_A(config-subif)#end
Task 10: Save the Router Configuration
Enter the copy run start command to save the current running configuration to NVRAM.
Task 11: Display the Router Routing Table
Enter show ip route at the privileged EXEC mode prompt.
Router_A#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.5.0/24 is directly connected, FastEthernet0/0.2
C 192.168.7.0/24 is directly connected, FastEthernet0/0.3
C 192.168.1.0/24 is directly connected, FastEthernet0/0.1
Router_A#
Do entries exist in the routing table? Yes, 3
What interface are the entries pointing to? Fast Ethernet 0/0
Why is there not a need to run a routing protocol?
All interfaces are connected.

Task 12: Test the VLANs and the Trunk
Step 1. To test the VLANs and the trunk, ping from the host in Switch_A port 0/9 to the host in port
0/5.
Was the ping successful? Yes
Why?
The trunk to the router forwarded packets from VLAN 20 to VLAN 10.
Step 2. Ping from the host in Switch_A port 0/5 to the switch IP 192.168.1.2.
Was the ping successful? Yes
Task 13: Move the Hosts
Move the hosts to other VLANs and try pinging the management VLAN 1. Note the results.
All pings should be successful with correct IP settings on the host.
After you complete the previous step, log off (by typing exit) and turn all the devices off. Then, remove
and store the cables and adapter.
Switch_A
Switch_A#show running-config
Building configuration...
Current configuration : 2053 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Switch_A
!
enable secret 5 $1$5kx7$u7JjZnEXhjhJ0cJIplN4t.
!
ip subnet-zero
!
spanning-tree mode pvst
no spanning-tree optimize bpdu transmission
spanning-tree extend system-id
!
interface FastEthernet0/1
switchport mode trunk
no ip address
!
interface FastEthernet0/2
no ip address
!
interface FastEthernet0/3
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428 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
no ip address
!
interface FastEthernet0/4
no ip address
!
interface FastEthernet0/5
switchport access vlan 10
switchport mode access
no ip address
!
interface FastEthernet0/6
switchport access vlan 10
switchport mode access
no ip address
!
interface FastEthernet0/7
switchport access vlan 10
switchport mode access
no ip address
!
interface FastEthernet0/8
switchport access vlan 10
switchport mode access
no ip address
!
interface FastEthernet0/9
switchport access vlan 20
switchport mode access
no ip address
!
interface FastEthernet0/10
switchport access vlan 20
switchport mode access
no ip address
!
interface FastEthernet0/11
switchport access vlan 20
switchport mode access
no ip address
!
interface FastEthernet0/12
switchport access vlan 20
switchport mode access
no ip address
!
interface FastEthernet0/13

no ip address
!
interface FastEthernet0/14
no ip address
!
interface FastEthernet0/15
no ip address
!
interface FastEthernet0/16
no ip address
!
interface FastEthernet0/17
no ip address
!
interface FastEthernet0/18
no ip address
!
interface FastEthernet0/19
no ip address
!
interface FastEthernet0/20
no ip address
!
interface FastEthernet0/21
no ip address
!
interface FastEthernet0/22
no ip address
!
interface FastEthernet0/23
no ip address
!
interface FastEthernet0/24
no ip address
!
interface Vlan1
ip address 192.168.1.2 255.255.255.0
no ip route-cache
!
ip default-gateway 192.168.1.1
ip http server
!
line con 0
password cisco
login
line vty 0 4
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430 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
password cisco
login
line vty 5 15
password cisco
login
!
end
Switch_B
Router_A#show runnig-config
Building configuration...
Current configuration : 863 bytes
!
version 12.2
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router_A
!
enable secret 5 $1$ihY0$.S.8M7iVky3u28ZYmHgWx1
!
ip subnet-zero
!
call rsvp-sync
!
interface FastEthernet0/0
no ip address
duplex auto
speed auto
!
interface FastEthernet0/0.1
encapsulation dot1Q 1 native
ip address 192.168.1.1 255.255.255.0
!
interface FastEthernet0/0.2
encapsulation dot1Q 10
ip address 192.168.5.1 255.255.255.0
!
interface FastEthernet0/0.3
encapsulation dot1Q 20
ip address 192.168.7.1 255.255.255.0
!
interface Serial0/0
no ip address

shutdown
no fair-queue
!
interface Serial0/1
no ip address
shutdown
!
ip classless
ip http server
!
!
!
dial-peer cor custom
!
line con 0
password cisco
login
line aux 0
line vty 0 4
password cisco
login
!
end
Comprehensive Lab 9-5: Inter-VLAN and VTP
Configuration
Note: This lab continues where Challenge Lab 8-4, “Static VLANs, STP, and Port Security” ended. You need to complete
that lab before proceeding with this lab. Another option is to continue on to Challenge Lab 9-6, “Advanced
Switching,” which is not dependent on any previous labs.
Figure 9-8 Inter-VLAN and VTP Configuration
VLAN 1 10.1.0.0/16
VLAN 10 10.10.0.0/16
VLAN 20 10.20.0.0/16
VLAN 30 10.30.0.0/16
VLAN 10
fa0/4–8
fa0/1
802.1q Trunk
fa0/1
RTA
SWA
VLAN 20
fa0/9–16
VLAN 1: 10.1.0.2
DefGate: 10.1.0.1
fa0/2
fa0/3
VLAN 30
fa0/17–24
VLAN 10
fa0/4–8
Chapter 9: VLAN Trunking Protocol 431
VLAN 1: 10.1.0.3
DefGate: 10.1.0.1
fa0/2
fa0/3 SWB
VLAN 20
fa0/9–16
VLAN 30
fa0/17–24

432 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Table 9-6 Addressing Scheme
Device Interface IP Address Subnet
Mask
SWA VLAN 1 10.1.0.2 255.255.0.0
SWB VLAN 1 10.1.0.3 255.255.0.0
RTA Fa0/1.1 10.1.0.1 255.255.0.0
Objectives
■ Delete the VLAN database.
■ Configure VTP parameters.
■ Configure inter-VLAN routing.
■ Modify VLANs.
■ Verify and document configurations.
Fa0/1.10 10.10.0.1 255.255.0.0
Fa0/1.20 10.20.0.1 255.255.0.0
Fa0/1.30 10.30.0.1 255.255.0.0
The topology shown in Figure 9-8 is using 2950 switches and a 2621 router. You can also use a 1700
series router that supports VLAN trunking.
NetLab Compatibility Notes
This lab is fully compatible with a standard NetLab Basic Switch Pod.
Task 1: Cable the Topology and Basic Configuration
Step 1. SWA and SWB should be loaded with your saved configurations for Challenge Lab 8-4, “Static
VLANs, STP, and Port Security.” If you did not complete that lab, you need to do so now.
Step 2. Configure RTA with basic router configurations, including:
■ Hostname
■ Line configurations
■ Global passwords
■ Host tables
■ Banner
■ Other instructor-required global configurations
Task 2: Configure VTP Parameters
Step 1. SWA will be the VTP server. Configure SWA with the domain name CCNA3 and password
cisco. Verify your configuration with the show vtp status command.
SWA#show vtp status
VTP Version : 2
Configuration Revision : 3
Maximum VLANs supported locally : 250
Number of existing VLANs : 8

VTP Operating Mode : Server
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x3B 0x01 0x37 0x7F 0x25 0x20 0xD0 0x0F
Configuration last modified by 0.0.0.0 at 3-1-93 00:30:56
Local updater ID is 10.1.0.2 on interface Vl1 (lowest numbered VLAN interface
found)
Step 2. Notice in the preceding output that the configuration revision number is 3. Why?
Three VLANs have been added (Accounting VLAN 10, Marketing VLAN 20, and Purchasing
VLAN 30). The configuration revision number increments by 1 each time a change is made.
Step 3. On SWB, you need to remove the current VLAN configurations and reload the switch. What
command will delete the VLAN database file?
SWB#delete flash:vlan.dat
Delete filename [vlan.dat]?
Delete flash:vlan.dat? [confirm]
SWB#reload
Proceed with reload? [confirm]
Step 4. After you delete the VLAN database and reload the switch, your show vlan brief command
should display the following:
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 5. Your VTP status should display the following output. Take note of the configuration revision
number, the operating mode, and the domain name.
SWB#show vtp status
VTP Version : 2
Configuration Revision : 0
Maximum VLANs supported locally : 64
Number of existing VLANs : 5
VTP Operating Mode : Server
VTP Domain Name :
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434 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x57 0xCD 0x40 0x65 0x63 0x59 0x47 0xBD
Configuration last modified by 0.0.0.0 at 0-0-00 00:00:00
Local updater ID is 10.1.0.3 on interface Vl1 (lowest numbered VLAN interface
found)
Step 6. Enter the commands to configure SWB as a VTP client on the CCNA3 VTP domain with the
password cisco. Record the commands you used.
SWB(config)#vtp mode client
Setting device to VTP CLIENT mode.
SWB(config)#vtp domain CCNA3
Changing VTP domain name from NULL to CCNA3
SWB(config)#vtp password cisco
Setting device VLAN database password to cisco
Step 7. It may take a while for SWB to receive a VTP message from the server, because, unless there
is a change or unless a request is made, the server sends out VTP advertisements only every 5
minutes. You can speed up the process by shutting down the trunks attached to SWA and then
reactivating them. This will force an exchange of VTP messages. Verify SWB now has the
VLAN information from SWA.
SWB#show vtp status
VTP Version : 2
Configuration Revision : 3
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x3B 0x01 0x37 0x7F 0x25 0x20 0xD0 0x0F
Configuration last modified by 0.0.0.0 at 3-1-93 00:30:56
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11,
Fa0/12
Fa0/13, Fa0/14, Fa0/15,
Fa0/16
30 Purchasing
Fa0/24
active Fa0/17, Fa0/18, Fa0/19,
Fa0/20
Fa0/21, Fa0/22, Fa0/23,
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

Task 3: Configure Inter-VLAN Routing
Step 1. The Fast Ethernet interface on RTA that is attached to SWA will trunk VLANs. Make sure you
configure the Fa0/1 port on SWA to trunking mode and activate it.
RTA(config)#interface FastEthernet0/1
RTA(config-if)#no shutdown
Step 2. Configure RTA to trunk for all three VLANs by using the subinterface designations and IP
addresses shown in Table 9-6. Make sure the physical interface is activated. Also, for VLAN 1,
make sure you add the native argument to the end of the encapsulation command.
RTA(config-if)#interface FastEthernet0/1.1
RTA(config-subif)#encapsulation dot1Q 1 native
RTA(config-subif)#ip address 10.1.0.1 255.255.0.0
RTA(config-subif)#interface FastEthernet0/1.10
RTA(config-subif)#encapsulation dot1Q 10
RTA(config-subif)#ip address 10.10.0.1 255.255.0.0
RTA(config-subif)#interface FastEthernet0/1.20
RTA(config-subif)#encapsulation dot1Q 20
RTA(config-subif)#ip address 10.20.0.1 255.255.0.0
RTA(config-subif)#interface FastEthernet0/1.30
RTA(config-subif)#encapsulation dot1Q 30
RTA(config-subif)#ip address 10.40.0.1 255.255.0.0
RTA(config-subif)#end
Chapter 9: VLAN Trunking Protocol 435
Output from the show ip interface brief command should look like the following:
RTA#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES unset administratively down down
Serial0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset up up
FastEthernet0/1.1 10.1.0.1 YES manual up up
FastEthernet0/1.10 10.10.0.1 YES manual up up
FastEthernet0/1.20 10.20.0.1 YES manual up up
FastEthernet0/1.30 10.30.0.1 YES manual up up
Step 3. Attach two workstations to the network. One should be attached to a port on SWA. Attach the
other to SWB on a port that belongs to a different VLAN from the workstation attached to
SWA. Document your choices in the space provided. Remember that the default gateway will
be the IP address of the router’s subinterface that belongs to the same VLAN.

436 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Workstation attached to SWA:
Port __________
VLAN __________
IP address ________________
Subnet mask _______________
Workstation attached to SWB:
Port __________
VLAN __________
IP address ________________
Subnet mask _______________
Step 4. Verify that the two workstations can ping each other. If they cannot, troubleshoot.
Task 4: Adding, Moving, and Deleting VLANs
Step 1. A few employees from the Warehousing department are relocating to the office serviced by the
SWB switch. Create a new VLAN 40 named Warehousing. Record the commands, including
switch prompt, to create this new VLAN.
SWA(config)#vlan 40
SWA(config-vlan)#name Warehousing
Step 2. Verify that SWB has incremented its VTP configuration revision number and has the new
VLAN listed.
SWB#show vtp status
VTP Version : 2
Configuration Revision : 4
Maximum VLANs supported locally : 64
Number of existing VLANs : 9
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xBC 0xD2 0x4A 0x5B 0xF3 0x03 0x26 0x75
Configuration last modified by 10.1.0.2 at 3-1-93 01:17:40
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24

40 Warehousing active
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 3. Because the Purchasing department has only four employees in the office serviced by SWB,
reassign the last four ports on SWB to the new Warehousing VLAN. Record the commands
you used and verify your configuration with the show vlan brief command.
SWB(config)#interface range fa0/21 - 24
SWB(config-if-range)#switchport access vlan 40
SWB#show vlan brief
Chapter 9: VLAN Trunking Protocol 437
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
40 Warehousing active Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 4. The Purchasing department has been consolidated with the Accounting department. The
Purchasing employees on SWB have transferred to the office serviced by SWA. Record the
command to delete VLAN 30. Verify with the show vtp status and show vlan brief commands
on SWB.
SWA(config)#no vlan 30
SWA(config)#exit
SWB#show vtp status
VTP Version : 2
Configuration Revision : 5
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x80 0xED 0x23 0x29 0x92 0x92 0xBE 0x09
Configuration last modified by 10.1.0.2 at 3-1-93 02:07:29
SWB#show vlan brief

438 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
40 Warehousing active Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 5. Notice from the show vlan brief output for SWB that ports Fa0/17 through Fa0/20 are not
assigned to any VLAN. Correct this by assigning them to the Warehousing VLAN. Record the
commands you used and then verify with the show vlan brief command.
SWB(config)#interface range fa0/17 - 20
SWB(config-if-range)#switchport access vlan 40
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
40 Warehousing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 6. On SWA, assign the ports that belonged to the Purchasing VLAN to the Accounting VLAN.
Record the commands you used and then verify with the show vlan brief command.
SWA(config)#interface range fa0/17 - 24
SWA(config-if-range)#switchport access vlan 10
SWA#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Gi0/1, Gi0/2
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8, Fa0/17, Fa0/18, Fa0/19
Fa0/20, Fa0/21, Fa0/22, Fa0/23
Fa0/24

20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
40 Warehousing active
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
Step 7. If you attach a workstation to the Warehousing VLAN, it will not be able to ping any workstations
outside its own VLAN. Try it. Why were the pings unsuccessful?
Because RTA has not yet been configured to route for VLAN 40.
Chapter 9: VLAN Trunking Protocol 439
Step 8. Record and implement the configuration changes necessary to ensure that Warehousing workstations
have inter-VLAN communication ability. Verify that a Warehousing workstation can
ping another workstation attached to a different VLAN.
RTA(config)#no interface fa0/1.30
Not all config may be removed and may reappear after reactivating the subinterface
RTA(config)#interface fa0/1.40
RTA(config-subif)#description Warehousing VLAN 40
RTA(config-subif)#encapsulation dot1q 40
RTA(config-subif)#ip address 10.40.0.1 255.255.0.0
RTA(config-subif)#end
RTA#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES unset administratively down down
Serial0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset up up
FastEthernet0/1.1 10.1.0.1 YES manual up up
FastEthernet0/1.10 10.10.0.1 YES manual up up
FastEthernet0/1.20 10.20.0.1 YES manual up up
FastEthernet0/1.30 unassigned YES manual deleted down
FastEthernet0/1.40 10.40.0.1 YES manual up up

440 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 5: Documentation
Document your configurations by capturing the following output:
■ show run
■ show vlan brief
■ show vtp status
■ On RTA, capture show run and show ip interface brief
Final scripts and verification output:
RTA
!
hostname RTA
!
enable secret class
!
no ip domain lookup
ip host SWB 10.1.0.3
ip host SWA 10.1.0.2
!
interface FastEthernet0/1
no shutdown
!
interface FastEthernet0/1.1
description Management VLAN 1
encapsulation dot1Q 1 native
ip address 10.1.0.1 255.255.0.0
!
interface FastEthernet0/1.10
description Accounting VLAN 10
encapsulation dot1Q 10
ip address 10.10.0.1 255.255.0.0
!
interface FastEthernet0/1.20
description Marketing VLAN 20
encapsulation dot1Q 20
ip address 10.20.0.1 255.255.0.0
!
interface FastEthernet0/1.40
description Warehousing VLAN 40
encapsulation dot1Q 40
ip address 10.40.0.1 255.255.0.0
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************

$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
end
RTA#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES unset administratively down down
Serial0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset up up
FastEthernet0/1.1 10.1.0.1 YES manual up up
FastEthernet0/1.10 10.10.0.1 YES manual up up
FastEthernet0/1.20 10.20.0.1 YES manual up up
FastEthernet0/1.30 unassigned YES manual deleted down
FastEthernet0/1.40 10.40.0.1 YES manual up up
SWA !————————————————————
!VTP and VLAN configuration does not show
!————————————————————
enable
config t
vtp mode server
vtp domain CCNA3
vtp password cisco
Chapter 9: VLAN Trunking Protocol 441

442 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
vlan 10
name Accounting
vlan 20
name Marketing
vlan 40
name Warehousing
!————————————————————
!
hostname SWA
!
enable secret class
!
no ip domain-lookup
ip host SWB 10.1.0.3
ip host RTA 10.1.0.1
!
interface FastEthernet0/1
!
switchport mode trunk
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk
interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/17 - 24
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky

!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 10.1.0.2 255.255.0.0
no shutdown
ip default-gateway 10.1.0.1
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
SWA#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1, Gi0/1, Gi0/2
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8, Fa0/17, Fa0/18, Fa0/19
Fa0/20, Fa0/21, Fa0/22, Fa0/23
Fa0/24
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
40 Warehousing active
1002 fddi-default active
Chapter 9: VLAN Trunking Protocol 443
Fa0/13, Fa0/14, Fa0/15, Fa0/16

444 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWA#show vtp status
VTP Version : 2
Configuration Revision : 5
Maximum VLANs supported locally : 250
Number of existing VLANs : 8
VTP Operating Mode : Server
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x80 0xED 0x23 0x29 0x92 0x92 0xBE 0x09
Configuration last modified by 10.1.0.2 at 3-1-93 02:07:29
Local updater ID is 10.1.0.2 on interface Vl1 (lowest numbered VLAN interface found)
SWB !————————————————————
!VTP and VLAN configuration does not show
!————————————————————
enable
config t
vtp mode client
vtp domain CCNA3
vtp password cisco
!————————————————————
!
hostname SWB
!
enable secret class
!
no ip domain-lookup
ip host SWA 10.1.0.2
ip host RTA 10.1.0.1
!
interface FastEthernet0/1
!
shutdown
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk

interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/17 - 24
switchport access vlan 40
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 10.1.0.3 255.255.0.0
no shutdown
ip default-gateway 10.1.0.1
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
Chapter 9: VLAN Trunking Protocol 445

446 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
line vty 5 15
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
40 Warehousing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWB#show vtp status
VTP Version : 2
Configuration Revision : 5
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
Fa0/21, Fa0/22, Fa0/23, Fa0/24
MD5 digest : 0x80 0xED 0x23 0x29 0x92 0x92 0xBE 0x09
Configuration last modified by 10.1.0.2 at 3-1-93 02:07:29

Challenge Lab 9-6: Advanced Switching
Figure 9-9 Advanced Switching Challenge Lab
Table 9-7 Addressing Scheme
Device Interface IP Address Subnet Mask
SWA VLAN 1 172.16.39.2 255.255.255.248
SWB VLAN 1 172.16.39.3 255.255.255.248
DIST Fa0/1.1 172.16.39.1 255.255.255.248
Objectives
■ Configure STP.
■ Configure port security.
■ Configure the VTP server and client.
■ Configure and assign VLANs.
■ Configure inter-VLAN routing.
■ Verify and document configurations.
Equipment
VLAN 10
fa0/4–8
fa0/1
802.1q Trunk
fa0/1
Fa0/1.10 172.16.32.1 255.255.252.0
Fa0/1.20 172.16.36.1 255.255.254.0
Fa0/1.30 172.16.38.1 255.255.255.0
The topology shown in Figure 9-9 is using 2950 switches and a 2621 router. You can also use a 1700
series router that supports VLAN trunking.
NetLab Compatibility Notes
DIST
SWA
VLAN 20
fa0/9–16
fa0/2
fa0/3 802.1q Trunk
VLAN 30
fa0/17–24
VLAN 10
fa0/4–8
Chapter 9: VLAN Trunking Protocol 447
VLAN 1 172.16.39.0/29
VLAN 10 172.16.32.0/22
VLAN 20 172.16.36.0/23
VLAN 30 172.16.38.0/24
This lab is fully compatible with a standard NetLab Basic Switch Pod although you will not be able to
fully test your VLANs or port security.
fa0/2
fa0/3
SWB
VLAN 20
fa0/9–16
VLAN 30
fa0/17–24

448 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 1: Cable the Topology and Basic Configuration
Step 1. Choose two 2950 switches and one router with a Fast Ethernet interface (1700 or 2600) and
cable them according to the topology. (If using NetLab, choose a switch router pod.)
Step 2. Configure the switches and router according to your instructor’s required basic configuration
hostnames, host tables, lines, and banner. Configure each of the switches with the correct
VLAN 1 IP addresses and the correct default gateway.
Step 3. Verify connectivity between SWA and SWB. Pings should be successful. If they are not, troubleshoot.
Task 2: Configure the Root Bridge for STP
Step 1. SWA should always be the root bridge. Configure SWA with a spanning-tree priority of 4096
for all four VLANs (1, 10, 20, and 30).
Step 2. Verify that SWA is the root with the show spanning-tree summary command. SWA should be
listed as the root bridge, as shown in the following output.
SWA#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0001, VLAN0010, VLAN0020, VLAN0030
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 0 0 0 3 3
VLAN0010 0 0 0 3 3
VLAN0020 0 0 0 3 3
VLAN0030 0 0 0 3 3
——————————— ———— ————- ———— ————— —————
4 vlans 0 0 0 12 12
SWB#show spanning-tree summary
Switch is in pvst mode
Root bridge for: none
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short

Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 1 0 0 1 2
VLAN0010 1 0 0 1 2
VLAN0020 1 0 0 1 2
VLAN0030 1 0 0 1 2
——————————— ———— ————- ———— ————— —————
4 vlans 4 0 0 4 8
Task 3: Configure Port Security
Step 1. As a security precaution, disable the Fast Ethernet 0/1 interface on SWB, because this interface
will not be used for access mode or trunk mode.
Perform the following steps on both SWA and SWB.
Chapter 9: VLAN Trunking Protocol 449
Step 2. Configure the access ports (Fa0/4 to 24) for access mode and turn on port security.
Step 3. Enter the command to make the first MAC address learned “stick” to the port. No other MAC
addresses should be allowed (maximum of one MAC per port).
Step 4. Enter the command that will automatically shut down the port if a security violation occurs.
Step 5. Verify port security with the show port-security command. Your output should look similar to
the following:
SWA#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security
Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 0 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 0 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 0
Max Addresses limit in System : 1024

450 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
SWB#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security
Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 0 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 0 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 0
Max Addresses limit in System : 1024
Task 4: Configure VTP and VLANs
Step 1. Configure SWA as the VTP server with the domain name CCNA3 and password cisco.
Configure SWB as a VTP client in the same domain using the same password.
Step 2. Configure VLANs with names on the VTP server.
■ VLAN 10 is the Accounting VLAN.
■ VLAN 20 is the Marketing VLAN.
■ VLAN 30 is the Purchasing VLAN.
Step 3. Configure the appropriate ports on SWA and SWB for trunking. Verify trunking is properly
configured with the show interface trunk command on both SWA and SWB.
SWA#show interface trunk
Port Mode Encapsulation Status Native vlan
Fa0/1 on 802.1q trunking 1
Fa0/2 on 802.1q trunking 1
Fa0/3 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/1 1-4094
Fa0/2 1-4094

Fa0/3 1-4094
Port Vlans allowed and active in management domain
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Port Vlans in spanning tree forwarding state and not pruned
Fa0/1 1,10,20,30
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
SWB#show interface trunk
Port Mode Encapsulation Status Native vlan
Fa0/2 on 802.1q trunking 1
Fa0/3 on 802.1q trunking 1
Port Vlans allowed on trunk
Fa0/2 1-4094
Fa0/3 1-4094
Port Vlans allowed and active in management domain
Fa0/2 1,10,20,30
Fa0/3 1,10,20,30
Port Vlans in spanning tree forwarding state and not pruned
Fa0/2 1,10,20,30
Fa0/3 none
Step 4. Assign access ports to their correct VLAN as specified in the topology.
Step 5. Verify both the VTP status and VLAN configuration on both switches with the show vtp status
and show vlan brief commands. Your output should look similar to the following:
SWA#show vtp status
VTP Version : 2
Configuration Revision : 1
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Server
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xE0 0x67 0x70 0x4A 0x3C 0xAB 0x44 0x67
Configuration last modified by 172.16.39.2 at 3-10-93 01:23:32
Local updater ID is 172.16.39.2 on interface Vl1 (lowest numbered VLAN interface
found)
SWA#show vlan brief
Chapter 9: VLAN Trunking Protocol 451
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-

452 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
1 default active
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWB#show vtp status
VTP Version : 2
Configuration Revision : 1
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xE0 0x67 0x70 0x4A 0x3C 0xAB 0x44 0x67
Configuration last modified by 172.16.39.2 at 3-10-93 01:23:32
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

Task 5: Set Up DHCP on the DIST Router
Although DHCP (Dynamic Host Configuration Protocol) is a CCNA 4 objective, it will help in this lab to
use dynamic assignment of IP addresses. Later in the lab, when you connect a workstation to one of the
switches, a DHCP broadcast will be sent to DIST. DIST will send a DHCP offer to your workstation with
an appropriate IP address for the VLAN the workstation is attached to. Make sure your workstations are
set to “Obtain IP address automatically.” Add the following commands while in global configuration mode
on DIST:
ip dhcp excluded-address 172.16.32.1 172.16.32.10
ip dhcp excluded-address 172.16.36.1 172.16.36.10
ip dhcp excluded-address 172.16.38.1 172.16.38.10
!
ip dhcp pool VLAN10
network 172.16.32.0 255.255.252.0
default-router 172.16.32.1
!
ip dhcp pool VLAN20
network 172.16.36.0 255.255.254.0
default-router 172.16.36.1
!
ip dhcp pool VLAN30
network 172.16.38.0 255.255.255.0
default-router 172.16.38.1
Task 6: Configure Inter-VLAN Routing
Configure DIST to route all VLANs by completing the following:
Step 1. Activate the physical interface.
Step 2. Create subinterfaces for each of the four VLANs. Number each subinterface with the VLAN
number. For example, the VLAN 1 subinterface should be numbered fa0.1 or fa0/0.1, depending
on the router.
Step 3. Configure each subinterface for 802.1q trunking and assign each subinterface the first IP
address in the appropriate subnet for that VLAN (refer to the topology).
Step 4. Configure each subinterface with an appropriate description.
Chapter 9: VLAN Trunking Protocol 453
Step 5. Verify that the show ip interface brief command output is similar to the following output:
DIST#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 unassigned YES unset administratively down down
Serial0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset up up
FastEthernet0/1.1 172.16.39.1 YES manual up up
FastEthernet0/1.10 172.16.32.1 YES manual up up
FastEthernet0/1.20 172.16.36.1 YES manual up up
FastEthernet0/1.30 172.16.38.1 YES manual up up

454 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 6. Verify connectivity between all three devices. Each device should be able to ping the other two
devices.
DIST#ping SWA
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.39.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/4/8 ms
DIST#ping SWB
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.39.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms
SWB#ping SWA
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.39.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms
Task 7: Verify Inter-VLAN Routing
Step 1. Attach two workstations to different VLANs.
Step 2. Verify that each workstation received an IP address from the DHCP server on DIST.
Step 3. Verify that the two workstations can ping each other. Traceroute should show that the ping
packets are going through the router. The following is some sample output of this verification.
Yours should look similar.
——————————————————————————-
Configuration for a Workstation attached to VLAN 10
——————————————————————————-
C:\>ipconfig
Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 172.16.32.11
Subnet Mask . . . . . . . . . . . : 255.255.252.0
Default Gateway . . . . . . . . . : 172.16.32.1
——————————————————————————-
Configuration for a Workstation attached to VLAN 20
——————————————————————————-
C:\>ipconfig

Windows IP Configuration
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 172.16.36.11
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 172.16.36.1
——————————————————————-
VLAN 10 Workstation pings VLAN 20 workstation
——————————————————————-
C:\>ping 172.16.36.11
Pinging 172.16.36.11 with 32 bytes of data:
Reply from 172.16.36.11: bytes=32 time=2ms TTL=127
Reply from 172.16.36.11: bytes=32 time=1ms TTL=127
Reply from 172.16.36.11: bytes=32 time=1ms TTL=127
Reply from 172.16.36.11: bytes=32 timetracert 172.16.36.11
Tracing route to 172.16.36.12 over a maximum of 30 hops
1 1 ms 1 ms

456 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 000c.857f.9ea0 DYNAMIC Fa0/1
1 000d.28f2.6942 DYNAMIC Fa0/2
1 000d.28f2.6943 DYNAMIC Fa0/3
10 000c.857f.9ea0 DYNAMIC Fa0/1
10 000d.56a1.a975 STATIC Fa0/4
20 000c.857f.9ea0 DYNAMIC Fa0/1
20 000d.56a1.c8f7 STATIC Fa0/9
Total Mac Addresses for this criterion: 11
SWA#show run
!
interface FastEthernet0/4
switchport port-security mac-address sticky 000d.56a1.a975
!
interface FastEthernet0/9
switchport port-security mac-address sticky 000d.56a1.c8f7
Step 5. Enter the show port-security command. The output should now show that the two ports are
counted.
SWA#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security
Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 1 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 1 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 2
Max Addresses limit in System : 1024

Chapter 9: VLAN Trunking Protocol 457
Step 6. Verify that a port currently used by one of your workstations will shut down when another
workstation is attached to the same port. When you attach the workstation, you will see the link
beat light go green for a brief moment. Then it will go dark as the port is automatically shut
down. On the switch console, you may get syslog messages similar to the following output.
2d23h: %LINK-3-UPDOWN: Interface FastEthernet0/4, changed state to down
2d23h: %PORT_SECURITY-2-PSECURE_VIOLATION: Security violation occurred,
caused by MAC address 000d.56a1.acfc on port Fa0/4.
2d23h: %PM-4-ERR_DISABLE: psecure-violation error detected on Fa0/4,
putting Fa0/4 in err-disable state
Step 7. Verify that the port is shut down with the show interface and show port-security commands.
SWA#show interface fastethernet 0/4
FastEthernet0/4 is down, line protocol is down (err-disabled)
SWA#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security
Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 1 1 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 1 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 2
Max Addresses limit in System : 1024
Step 8. Complete the procedures necessary to remove this port from the err-disabled state and allow
the new workstation’s MAC address to “stick” to the configuration.

458 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 8: Documentation
Document your configurations by capturing the following output:
■ show run
■ show vlan brief
■ show spanning-tree summary
■ show vtp status
■ show port-security
■ show mac-address-table
■ On DIST, capture show run
Final scripts and verification output:
DIST#
!
ena
config t
!
hostname DIST
!
enable secret class
!
ip dhcp excluded-address 172.16.32.1 172.16.32.10
ip dhcp excluded-address 172.16.36.1 172.16.36.10
ip dhcp excluded-address 172.16.38.1 172.16.38.10
!
ip dhcp pool VLAN10
network 172.16.32.0 255.255.252.0
default-router 172.16.32.1
!
ip dhcp pool VLAN20
network 172.16.36.0 255.255.254.0
default-router 172.16.36.1
!
ip dhcp pool VLAN30
network 172.16.38.0 255.255.255.0
default-router 172.16.38.1
!
no ip domain lookup
ip host SWB 172.16.39.3
ip host SWA 172.16.39.2
!
interface FastEthernet0/1
no shutdown
!
interface FastEthernet0/1.1

!
description Management VLAN 1
encapsulation dot1Q 1 native
ip address 172.16.39.1 255.255.255.248
interface FastEthernet0/1.10
!
description Accounting VLAN 10
encapsulation dot1Q 10
ip address 172.16.32.1 255.255.252.0
interface FastEthernet0/1.20
!
description Marketing VLAN 20
encapsulation dot1Q 20
ip address 172.16.36.1 255.255.254.0
interface FastEthernet0/1.30
!
description Purchasing VLAN 30
encapsulation dot1Q 30
ip address 172.16.38.1 255.255.255.0
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
end
SWA ena
config t
!————————————————————
Chapter 9: VLAN Trunking Protocol 459

460 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!VTP and VLAN configuration does not show
!————————————————————
vtp mode server
vtp domain CCNA3
vtp password cisco
vlan 10
name Accounting
vlan 20
name Marketing
vlan 30
name Purchasing
!————————————————————
!
hostname SWA
!
enable secret class
!
ip host SWB 172.16.39.3
ip host DIST 172.16.39.1
!
!
spanning-tree vlan 1 priority 4096
spanning-tree vlan 10 priority 4096
spanning-tree vlan 20 priority 4096
spanning-tree vlan 30 priority 4096
!
!
interface FastEthernet0/1
!
switchport mode trunk
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk
interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16
switchport access vlan 20

switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 172.16.39.2 255.255.255.248
no shutdown
ip default-gateway 172.16.39.1
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
SWA#show vlan brief
Chapter 9: VLAN Trunking Protocol 461

462 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Gi0/1, Gi0/2
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWA#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0001, VLAN0010, VLAN0020, VLAN0030
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Fa0/21, Fa0/22, Fa0/23, Fa0/24
Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 0 0 0 3 3
VLAN0010 0 0 0 3 3
VLAN0020 0 0 0 3 3
VLAN0030 0 0 0 3 3
——————————— ———— ————- ———— ————— —————
4 vlans 0 0 0 12 12
SWA#show vtp status
VTP Version : 2
Configuration Revision : 4
Maximum VLANs supported locally : 250
Number of existing VLANs : 8
VTP Operating Mode : Server
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled

MD5 digest : 0xDB 0xC6 0x01 0xD9 0x27 0x8E 0x51 0xF3
Configuration last modified by 172.16.39.2 at 3-1-93 00:07:50
Local updater ID is 172.16.39.2 on interface Vl1 (lowest numbered VLAN interface found)
!The output below was captured from a NetLab switch
!No workstations show. Your output should show ‘CurrentAddr’ for workstations
SWA#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 0 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 0 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 0
Max Addresses limit in System : 1024
!The output below was captured from a NetLab switch
!No workstations show. Your output should show workstation MACs
SWA#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
All 000e.385d.e380 STATIC CPU
Chapter 9: VLAN Trunking Protocol 463

464 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
SWB ena
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 000d.6562.e380 DYNAMIC Fa0/2
1 000d.6562.e382 DYNAMIC Fa0/2
1 000d.6562.e383 DYNAMIC Fa0/3
1 000e.382f.4d81 DYNAMIC Fa0/1
Total Mac Addresses for this criterion: 8
config t
!———————————————————
!VTP configuration does not show
!———————————————————
vtp mode client
vtp domain CCNA3
vtp password cisco
!———————————————————
!
hostname SWB
!
enable secret class
!
no ip domain-lookup
ip host SWA 172.16.39.2
ip host DIST 172.16.39.1
!
interface FastEthernet0/1
!
shutdown
interface FastEthernet0/2
!
switchport mode trunk
interface FastEthernet0/3
!
switchport mode trunk
interface range FastEthernet0/4 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/9 - 16

switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
!The ‘maximum’ command does not show in configuration
!
switchport port-security maximum 1
interface Vlan1
!
ip address 172.16.39.3 255.255.255.248
no shutdown
ip default-gateway 172.16.39.1
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
!
exec-timeout 0 0
password cisco
logging synchronous
login
end
Chapter 9: VLAN Trunking Protocol 465

466 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
SWB#show vlan brief
VLAN Name Status Ports
—— ———————————————— ————- ———————————————-
1 default active Fa0/1
10 Accounting active Fa0/4, Fa0/5, Fa0/6, Fa0/7
Fa0/8
20 Marketing active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 Purchasing active Fa0/17, Fa0/18, Fa0/19, Fa0/20
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
SWB#show spanning-tree summary
Switch is in pvst mode
Root bridge for: none
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Fa0/21, Fa0/22, Fa0/23, Fa0/24
Name Blocking Listening Learning Forwarding STP Active
——————————— ———— ————- ———— ————— —————
VLAN0001 1 0 0 1 2
VLAN0010 1 0 0 1 2
VLAN0020 1 0 0 1 2
VLAN0030 1 0 0 1 2
——————————— ———— ————- ———— ————— —————
4 vlans 4 0 0 4 8
SWB#show vtp status
VTP Version : 2
Configuration Revision : 4
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled

VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xDB 0xC6 0x01 0xD9 0x27 0x8E 0x51 0xF3
Configuration last modified by 172.16.39.2 at 3-1-93 00:07:50
!The output below was captured from a NetLab switch
!No workstations show. Your output should show ‘CurrentAddr’ for workstations
SWB#show port-security
Secure Port MaxSecureAddr CurrentAddr SecurityViolation Security Action
(Count) (Count) (Count)
———————————————————————————————————————-
Fa0/4 1 0 0 Shutdown
Fa0/5 1 0 0 Shutdown
Fa0/6 1 0 0 Shutdown
Fa0/7 1 0 0 Shutdown
Fa0/8 1 0 0 Shutdown
Fa0/9 1 0 0 Shutdown
Fa0/10 1 0 0 Shutdown
Fa0/11 1 0 0 Shutdown
Fa0/12 1 0 0 Shutdown
Fa0/13 1 0 0 Shutdown
Fa0/14 1 0 0 Shutdown
Fa0/15 1 0 0 Shutdown
Fa0/16 1 0 0 Shutdown
Fa0/17 1 0 0 Shutdown
Fa0/18 1 0 0 Shutdown
Fa0/19 1 0 0 Shutdown
Fa0/20 1 0 0 Shutdown
Fa0/21 1 0 0 Shutdown
Fa0/22 1 0 0 Shutdown
Fa0/23 1 0 0 Shutdown
Fa0/24 1 0 0 Shutdown
———————————————————————————————————————-
Total Addresses in System : 0
Max Addresses limit in System : 1024
!The output below was captured from a NetLab switch
!No workstations show. Your output should show workstation MACs
SWB#show mac-address-table
Mac Address Table
—————————————————————-
Vlan Mac Address Type Ports
—— —————- ———— ——-
Chapter 9: VLAN Trunking Protocol 467

468 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
All 000d.6562.e380 STATIC CPU
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0100.0cdd.dddd STATIC CPU
1 000e.382f.4d81 DYNAMIC Fa0/2
1 000e.385d.e382 DYNAMIC Fa0/2
10 000e.385d.e382 DYNAMIC Fa0/2
20 000e.385d.e382 DYNAMIC Fa0/2
30 000e.385d.e382 DYNAMIC Fa0/2
Total Mac Addresses for this criterion: 9

APPENDIX A
Router Interface Summary Chart
For most of the CCNA 3 labs, you need to examine the following chart to correctly reference the router
interface identifiers to use in commands based on the equipment in your lab.
Router Ethernet Ethernet Serial Serial
Model Interface 1 Interface 2 Interface 1 Interface 2
800 (806) Ethernet 0 (E0) Ethernet 1 (E1)
1600 Ethernet 0 (E0) Ethernet 1 (E1) Serial 0 (S0) Serial 1 (S1)
1700 FastEthernet 0 (FA0) FastEthernet 1 (FA1) Serial 0 (S0) Serial 1 (S1)
2500 Ethernet 0 (E0) Ethernet 1 (E1) Serial 0 (S0) Serial 1 (S1)
2600 FastEthernet 0/0 (FA0/0) FastEthernet 0/1 (FA0/1) Serial 0/0 (S0/0) Serial 0/1 (S0/1)
To find out exactly how the router is configured, look at the interfaces to identify what type and how many
the router has. There is no way to effectively list all of the combinations of configurations for each router
class. The chart provides the identifiers for the possible combinations of interfaces in the device. This
interface chart does not include any other type of interface even though a specific router might contain
one. An example of this is an ISDN BRI interface. The string in parentheses is the legal abbreviation that
you can use in Cisco IOS Software commands to represent the interface.

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APPENDIX B
Erasing and Reloading the Switch
For the majority of the labs in CCNA 3 focusing on switch configuration, it is necessary to start with a
basic unconfigured switch; otherwise, the configuration parameters you enter might combine with previous
ones and produce unpredictable results. The instructions here enable you to prepare the switch prior to performing
the lab so that previous configuration options do not interfere with your configurations.
The following is the procedure for clearing out previous configurations and starting with an unconfigured
switch. Instructions are provided for the 2900, 2950, and 1900 series switches.
2900 and 2950 Series Switches
Step 1. Disconnect the switch to be erased from all other switches. Verify that there is no uplink or
backbone cabling to any other switch, otherwise VLAN configuration information can be transferred
automatically.
Step 2. Enter into privileged EXEC mode by typing enable. If prompted for a password, enter class (if
that does not work, ask the instructor).
Switch> enable
Step 3. Remove the VLAN database information file:
Switch# delete flash:vlan.dat
Delete filename [vlan.dat]?[Enter]
Delete flash:vlan.dat? [confirm][Enter]
If there was no VLAN file, the following message appears:
%Error deleting flash:vlan.dat (No such file or directory)
Step 4. Remove the switch startup configuration file from NVRAM:
Switch#erase startup-config
The responding line prompt will be
Erasing the nvram filesystem will remove all files! Continue? [confirm]
Press Enter to confirm.
The response should be
Erase of nvram: complete
Step 5. Check that VLAN information was deleted.
Verify that the VLAN configuration was deleted in Step 3 using the show vlan command. If
previous VLAN configuration information (other than the default management VLAN 1) is still
present, it will be necessary to power cycle the switch (hardware restart) instead of issuing the
reload command. To power cycle the switch, remove the power cord from the back of the
switch or unplug it. Then plug it back in.
If the VLAN information was successfully deleted in Step 3, go to Step 6 and restart the switch
using the reload command.

472 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Step 6. Restart the software (using the reload command):
Note: This step is not necessary if the switch was restarted using the power cycle method.
1. In privileged EXEC mode, enter the command reload:
Switch(config)# reload
The responding line prompt will be
System configuration has been modified. Save? [yes/no]:
2. Type n and then press Enter.
The responding line prompt will be
Proceed with reload? [confirm][Enter]
The first line of the response will be
Reload requested by console.
After the switch has reloaded, the line prompt will be
Would you like to enter the initial configuration dialog? [yes/no]:
3. Type n and then press Enter.
The responding line prompt will be
Press RETURN to get started![Enter]
1900 Series Switches
Step 1. Remove VLAN Trunking Protocol (VTP) information:
#delete vtp
This command resets the switch with VTP parameters set to factory defaults.
All other parameters will be unchanged.
Reset system with VTP parameters set to factory defaults, [Y]es or [N]o?
Enter y and press Enter.
Step 2. Remove the switch startup configuration from NVRAM:
#delete nvram
This command resets the switch with factory defaults. All system
parameters will revert to their default factory settings. All static
and dynamic addresses will be removed.
Reset system with factory defaults, [Y]es or [N]o?
Enter y and press Enter.

APPENDIX C
Erasing and Reloading the Router
For some of the CCNA 3 labs, it is necessary to start with a basic unconfigured router; otherwise, the configuration
parameters you enter might combine with previous ones and produce unpredictable results. The
instructions here allow you to prepare the router prior to performing the lab so that previous configuration
options do not interfere with your configurations.
The following is the procedure for clearing out previous configurations and starting with an unconfigured
router.
Step 1. Enter into privileged EXEC mode by typing enable.
Router>enable
If prompted for a password, enter class. (If that does not work, ask your instructor.)
Step 2. In privileged EXEC mode, enter the command erase startup-config.
Router#erase startup-config
The response from the router will be
Erasing the nvram filesystem will remove all files! Continue? [confirm]
Step 3. Press Enter to confirm.
The response will be
Erase of nvram: complete
Step 4. Now in privileged EXEC mode, enter the command reload.
Router#reload
response:
System configuration has been modified. Save? [yes/no]:
Step 5. Type n and then press Enter.
The router will respond with the following:
Proceed with reload? [confirm]
Step 6. Press Enter to confirm.
The first line of the response will be
Reload requested by console.
After the router reloads, the prompt will be
Would you like to enter the initial configuration dialog? [yes/no]:
Step 7. Type n and then press Enter.
The responding prompt will be
Press RETURN to get started!
Step 8. Press Enter.
Now, the router is ready for you to perform the assigned lab.

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APPENDIX D
CCNA 3 Skills-Based Assessment Practice
Ultimately, your success on the CCNA exams, and in your networking career, will depend heavily upon
your ability to plan, design, implement, operate, and troubleshoot internetworks. In Switching Basics and
Intermediate Routing CCNA 3, you have learned many new skills. Now it is time to apply what you have
learned to comprehensive skills-based assessments. Because your CCNA 3 coursework is divided into
routing and switching, this appendix includes a skills-based assessment for routing and a skills-based
assessment for switching. Then, you will combine skills from both routing and switching in the CCNA 3
comprehensive skills-based assessment.
CCNA 3 Skills-Based Assessment: Routing
Figure D-1 CCNA 3 Skills-Based Assessment: Routing
Objectives
■ Configure OSPF with authentication
■ Configure EIGRP
■ Configure a default route and propagate it using OSPF
■ Verify network connectivity and gather documentation
Equipment
The topology shown in Figure D-1 is using 2600 series routers. However, you can use any router series
that supports OSPF, including the 1700 and 2500 series.
NetLab Compatibility Notes
OSPF
Area 0
172.16.1.2/30
S0/0
DCE
Router2
S0/0
DTE
10.10.1.1/30
S0/1
DCE
S0/1
DTE
Router1 Router3
Fa0/0
172.16.1.1/30
172.16.2.33/27
Fa0/0
172.30.1.1/24
This lab is fully compatible with a standard NetLab Basic Router Pod.
10.10.1.2/30
Fa0/0
172.30.2.1/24

476 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Preconfigurations
Use the following scripts to preconfigure the routers:
Router1
hostname Router1
interface FastEthernet0/0
ip address 172.16.2.33 255.255.255.224
no shutdown
interface Serial0/0
ip address 172.16.1.2 255.255.255.252
clockrate 56000
no shutdown
Router2
hostname Router2
interface FastEthernet0/0
ip address 172.30.1.1 255.255.255.0
no shutdown
interface Serial0/0
ip address 172.16.1.1 255.255.255.252
no shutdown
interface serial0/1
ip address 10.10.1.1 255.255.255.252
clockrate 56000
no shutdown
Router3
hostname Router3
interface FastEthernet0/0
ip address 172.30.2.1 255.255.255.0
no shutdown
interface serial0/1
ip address 10.10.1.2 255.255.255.252
no shutdown
Task 1: Configure OSPF with Authentication
Step 1. Use a loopback interface to configure Router1 with an OSPF router ID of 192.168.1.1.
Step 2. Use a loopback interface to configure Router2 with an OSPF router ID of 192.168.2.1.
Step 3. Configure OSPF routing between Router1 and Router2 with a process ID of 50.
Step 4. Configure OSPF so that only the following 172.16.0.0 subnets will be routed:
■ 172.16.2.32/27
■ 172.16.1.0/30
Step 5. Configure the OSPF hello interval to 5 seconds and the OSPF dead interval to 20 seconds.
Step 6. Configure the OSPF communication between the routers to use authentication with MD5
encryption.

Task 2: Configure EIGRP
Step 1. Configure EIGRP between Router2 and Router3 with an AS of 100.
Step 2. Configure EIGRP should only to route only for the following networks:
■ 10.10.1.0/30
■ 172.30.1.0/24
■ 172.30.2.0/24
Task 3: Configure Default Routing and Propagate It Using OSPF
Step 1. On Router2, configure a default static route to Router3.
Step 2. Propagate that default route to all routers in the OSPF routing domain.
Task 4: Verify Connectivity and Gather Documentation
Step 1. From Router2, verify connectivity by pinging all interfaces on all routers.
Step 2. From Router1, ping all OSPF-enabled interfaces.
Step 3. From Router3, ping all EIGRP-enabled interfaces.
Note: Router1 and Router3 will not be able to ping all interfaces, because there is no redistribution between OSPF
and EIGRP in this scenario.
Step 4. For each of the routers, capture the following output:
■ show run
■ show ip route
■ ping output showing successful pings according to Steps 1 to 3
Router1
Router1#show run
Building configuration...
hostname Router1
!
enable secret class
!
no ip domain lookup
ip host R2 172.16.1.1
!
interface Loopback0
ip address 192.168.1.1 255.255.255.0
!
interface FastEthernet0/0
ip address 172.16.2.33 255.255.255.224
no shutdown
!
Appendix D: CCNA 3 Skills-Based Assessment Practice 477

478 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface Serial0/0
description Link to R2
ip address 172.16.1.2 255.255.255.252
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
ip ospf dead-interval 20
clock rate 56000
no shutdown
!
router ospf 50
log-adjacency-changes
area 0 authentication message-digest
network 172.16.1.0 0.0.0.3 area 0
network 172.16.2.32 0.0.0.31 area 0
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
end
Router1#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route
Gateway of last resort is 172.16.1.1 to network 0.0.0.0
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
C 172.16.2.32/27 is directly connected, FastEthernet0/0
C 172.16.1.0/30 is directly connected, Serial0/0
C 192.168.1.0/24 is directly connected, Loopback0
O*E2 0.0.0.0/0 [110/1] via 172.16.1.1, 00:06:43, Serial0/0
Router1#ping 172.16.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/32/36 ms
Router1#ping 172.30.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.30.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/33/36 ms
Router1#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2005 by cisco Systems, Inc.
Compiled Mon 12-Dec-05 14:12 by evmiller
Image text-base: 0x80008098, data-base: 0x81A33618
ROM: System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
ROM: C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Router1 uptime is 44 minutes
System returned to ROM by power-on
System image file is "flash:c2600-j1s3-mz.123-17a.bin"
Appendix D: CCNA 3 Skills-Based Assessment Practice 479
cisco 2611XM (MPC860P) processor (revision 0x100) with 89088K/9216K bytes of mem
ory.
Processor board ID JAE07460SS1 (4270759778)
M860 processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
TN3270 Emulation software.
2 FastEthernet/IEEE 802.3 interface(s)

480 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
32768K bytes of processor board System flash (Read/Write)
Configuration register is 0x2102
Router2
Router2#show run
Building configuration...
hostname Router2
!
enable secret class
!
no ip domain lookup
ip host R1 172.16.1.2
ip host R3 10.10.1.2
!
interface Loopback0
ip address 192.168.2.1 255.255.255.0
!
interface FastEthernet0/0
ip address 172.30.1.1 255.255.255.0
no shutdown
!
interface Serial0/0
description Link to R1
ip address 172.16.1.1 255.255.255.252
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
ip ospf dead-interval 20
no shutdown
!
interface Serial0/1
description Link to R3
ip address 10.10.1.1 255.255.255.252
clock rate 56000
no clockrate
!
router eigrp 100
network 10.0.0.0
network 172.30.0.0
no auto-summary
!
router ospf 50
area 0 authentication message-digest

network 172.16.1.0 0.0.0.3 area 0
default-information originate
!
ip route 0.0.0.0 0.0.0.0 Serial0/1
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
end
Router2#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
Appendix D: CCNA 3 Skills-Based Assessment Practice 481
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
O 172.16.2.32/27 [110/65] via 172.16.1.2, 00:08:04, Serial0/0
C 172.16.1.0/30 is directly connected, Serial0/0
172.30.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.30.0.0/16 [90/2172416] via 10.10.1.2, 00:08:31, Serial0/1
C 172.30.1.0/24 is directly connected, FastEthernet0/0
10.0.0.0/30 is subnetted, 1 subnets

482 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
C 10.10.1.0 is directly connected, Serial0/1
C 192.168.2.0/24 is directly connected, Loopback0
S* 0.0.0.0/0 is directly connected, Serial0/1
Router2#ping 172.16.2.33
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.2.33, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 40/44/60 ms
Router2#ping 172.30.2.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.30.2.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 32/33/36 ms
Router2#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2005 by cisco Systems, Inc.
Compiled Mon 12-Dec-05 14:12 by evmiller
Image text-base: 0x80008098, data-base: 0x81A33618
ROM: System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
ROM: C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Router2 uptime is 43 minutes
System returned to ROM by power-on
System image file is "flash:c2600-j1s3-mz.123-17a.bin"
cisco 2621XM (MPC860P) processor (revision 0x100) with 118784K/12288K bytes of m
emory.
Processor board ID JAE07420G4S (1562611187)
M860 processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
TN3270 Emulation software.
2 FastEthernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
49152K bytes of processor board System flash (Read/Write)
Configuration register is 0x2102

Router3
Router3#show run
Building configuration...
!
hostname Router3
!
enable secret class
!
no ip domain lookup
ip host R2 10.10.1.1
!
interface FastEthernet0/0
ip address 172.30.2.1 255.255.255.0
no shutdown
!
interface Serial0/1
description Link to R2
ip address 10.10.1.2 255.255.255.252
no shutdown
!
router eigrp 100
network 10.0.0.0
network 172.30.0.0
auto-summary
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
Appendix D: CCNA 3 Skills-Based Assessment Practice 483

484 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
exec-timeout 0 0
password cisco
logging synchronous
login
end
Router3#show ip route
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
172.30.0.0/16 is variably subnetted, 3 subnets, 2 masks
C 172.30.2.0/24 is directly connected, FastEthernet0/0
D 172.30.0.0/16 is a summary, 00:12:12, Null0
D 172.30.1.0/24 [90/2172416] via 10.10.1.1, 00:12:11, Serial0/1
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
C 10.10.1.0/30 is directly connected, Serial0/1
D 10.0.0.0/8 is a summary, 00:12:12, Null0
Router3#ping 172.30.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.30.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 40/44/64 ms
Router3#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2005 by cisco Systems, Inc.
Compiled Mon 12-Dec-05 14:12 by evmiller
Image text-base: 0x80008098, data-base: 0x81A33618
ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)
ROM: C2600 Software (C2600-J1S3-M), Version 12.3(17a), RELEASE SOFTWARE (fc2)
Router3 uptime is 44 minutes
System returned to ROM by power-on

System image file is "flash:c2600-j1s3-mz.123-17a.bin"
Appendix D: CCNA 3 Skills-Based Assessment Practice 485
cisco 2621 (MPC860) processor (revision 0x102) with 56320K/9216K bytes of memory
.
Processor board ID JAD04300B3P (4106725847)
M860 processor: part number 0, mask 49
Bridging software.
X.25 software, Version 3.0.0.
TN3270 Emulation software.
2 FastEthernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read/Write)

486 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Configuration register is 0x2102
CCNA 3 Skills-Based Assessment: Switching
Figure D-2 CCNA 3 Skills-Based Assessment: Switching
Objectives
■ Router VLAN configuration
■ Basic switch configuration
■ Configure trunk links and port security
■ Configure STP, VTP, and VLANs
■ Configure VLAN interfaces on switches
■ Configure VLAN trunking and spanning tree
■ Verify connectivity and gather documentation
Equipment
VLAN 1
172.16.1.0/24
R1
Fa0/1
Trunk
802.1Q
Fa0/1
The topology shown in Figure D-2 has been designed for the 2950 series switch. Other hardware may have
different interface types and numbers. 1900 series switches do not support 802.1Q encapsulation and thus
require ISL encapsulation.
NetLab Compatibility Notes
This lab is fully compatible with a standard NetLab Basic Switch Pod.
Task 1: Router VLAN Configuration
Step 1. Configure the router hostname and any other basic configurations required by your instructor.
Step 2. Configure the Ethernet interface to trunk for each VLAN on S1—VLAN 1, VLAN 10, and
VLAN 20 using 802.1Q encapsulation:
Note: 1900 series switches do not support 802.1Q encapsulation. Use ISL encapsulation for 1900 series switches.
■ VLAN 1 = 172.16.1.0/24
Fa0/2 Trunk
Fa0/2
S1 Fa0/3 802.1Q Fa0/3 S2
VLAN 10
Accounting
172.16.10.0/24
VLAN 20
Marketing
172.16.20.0/24
VLAN 1
172.16.1.0/24
VLAN 10
Accounting
172.16.10.0/24
VLAN 20
Marketing
172.16.20.0/24

■ VLAN 10 = 172.16.10.0/24
■ VLAN 20 = 172.16.20.0/24
Task 2: Basic Switch Configuration
Step 1. Configure the hostname on switch S1 to S1.
Step 2. Configure S1 with a VLAN 1 IP address of 172.16.1.3/24.
Step 3. Configure the hostname on S2 to S2.
Step 4. Configure S2 with a VLAN 1 IP address of 172.16.1.4/24.
Step 5. Configure both switches with a default gateway address of 172.16.1.1.
Task 3: Configure Trunk Links and Port Security
Step 1. On S1, configure interfaces Fa0/1–3 in trunking mode.
Step 2. On S2, configure interface Fa0/2–3 in trunking mode. Shut down interface Fa0/1, because it
will not be used.
Note: If you are using a 2900 series switch, you have to specify the encapsulation type used on the
switch’s trunk links.
Step 3. On both switches, configure the following on interfaces Fa0/4–24 (or 12 if using a 12-port
switch):
■ Set the ports to access mode.
■ Enable port security.
■ Enable the first MAC address to stick to the configuration.
■ Enable port shutdown if there is a security violation.
Task 4: Configure STP, VTP, and VLANs
Step 1. Configure S1 to be the root bridge for VLAN 1 and VLAN 10.
Step 2. Configure S2 to be the root bridge for VLAN 20.
Step 3. Configure both S1 and S2 as part of VTP domain Group1.
Step 4. Configure S1 as the VTP server and S2 as the VTP client.
Step 5. Configure cisco as the VTP password.
Step 6. Create VLAN 10 with the name Accounting.
Step 7. Create VLAN 20 with the name Marketing.
Task 5: Configure VLAN Interfaces on Switches
Step 1. Configure the following on switch S1:
■ Assign interfaces Fa0/4–6 to VLAN 10.
■ Assign interfaces Fa0/7–9 to VLAN 20.
■ Verify that all other interfaces are in VLAN 1.
Step 2. Configure the following on switch S2:
■ Assign interfaces Fa0/4–6 to VLAN 10.
Appendix D: CCNA 3 Skills-Based Assessment Practice 487

488 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
■ Assign interfaces Fa0/7–9 to VLAN 20.
■ Verify that all other interfaces are in VLAN 1.
Task 6: Configure VLAN Trunking and Spanning Tree
Step 1. Configure trunking between S1 and S2 with 802.1Q encapsulation using ports Fa0/2 and Fa0/3
on both switches.
Note: Use ISL encapsulation for 1900 series switches.
Step 2. Configure S1 for trunking between S1 and R1 with 802.1Q encapsulation using port Fa0/1.
Step 3. Configure S1 to be the root bridge for VLAN 1
Task 7: Verify Connectivity and Gather Documentation
Step 1. It is not possible to verify inter-VLAN routing, because there are no hosts attached. However,
the router and the two switches should be able to ping each other on their VLAN 1 interfaces.
Step 2. For the router, capture the following output:
■ show run
■ show ip interface brief
Step 3. For the switches, capture the following output:
R1
■ show run
■ show vlan brief
■ show vtp status
■ show spanning-tree summary
R1#show run
Building configuration...
hostname R1
!
enable secret class
!
no ip domain lookup
ip host S2 172.16.1.4
ip host S1 172.16.1.3
!
interface FastEthernet0/1
no shutdown
!
interface FastEthernet0/1.1
description Managment VLAN 1
encapsulation dot1Q 1 native
ip address 172.16.1.1 255.255.255.0
!
interface FastEthernet0/1.10

description Accounting VLAN 10
encapsulation dot1Q 10
ip address 172.16.10.1 255.255.255.0
!
interface FastEthernet0/1.20
description Marketing VLAN 20
encapsulation dot1Q 20
ip address 172.16.20.1 255.255.255.0
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
end
Appendix D: CCNA 3 Skills-Based Assessment Practice 489
R1#show ip interface brief
Interface IP-Address OK? Method Status Prot
ocol
FastEthernet0/0 unassigned YES unset administratively down down
Serial0/0 unassigned YES unset administratively down down
FastEthernet0/1 unassigned YES unset up up
FastEthernet0/1.1 172.16.1.1 YES manual up up
FastEthernet0/1.10 172.16.10.1 YES manual up up
FastEthernet0/1.20 172.16.20.1 YES manual up up

490 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
R1#show version
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IPBASE-M), Version 12.3(1a), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Fri 06-Jun-03 22:08 by dchih
Image text-base: 0x80008098, data-base: 0x80F9CF68
ROM: System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
R1 uptime is 1 hour, 47 minutes
System returned to ROM by power-on
System image file is "flash:c2600-ipbase-mz.123-1a.bin"
cisco 2621XM (MPC860P) processor (revision 0x100) with 125952K/5120K bytes of me
mory.
Processor board ID JAE07420G7D (326445113)
M860 processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
2 FastEthernet/IEEE 802.3 interface(s)
1 Serial network interface(s)
32K bytes of non-volatile configuration memory.
49152K bytes of processor board System flash (Read/Write)
Configuration register is 0x2142 (will be 0x2102 at next reload)
S1
S1#show run
Building configuration...
hostname S1
!
enable secret class
!
no ip domain-lookup
ip host R1 172.16.1.1
ip host S2 172.16.1.4
!
!
spanning-tree vlan 1 priority 24576
spanning-tree vlan 10 priority 24576
!
!------------------------------------------
!VTP and VLAN Configurations
!----------------------------------------vtp
mode server

vtp domain Group1
vtp password cisco
vlan 10
name Accounting
vlan 20
name Marketing
!------------------------------------------
!
interface FastEthernet0/1
switchport mode trunk
!
interface FastEthernet0/2
switchport mode trunk
!
interface FastEthernet0/3
switchport mode trunk
!
interface range FastEthernet0/4 - 6
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/7 - 9
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/10 - 24
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface Vlan1
ip address 172.16.1.3 255.255.255.0
no shutdown
!
ip default-gateway 172.16.1.1=
!
Appendix D: CCNA 3 Skills-Based Assessment Practice 491

492 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
exec-timeout 0 0
password cisco
logging synchronous
login
!
end
S1#show vlan brief
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/10, Fa0/11, Fa0/12, Fa0/13
Fa0/14, Fa0/15, Fa0/16, Fa0/17
Fa0/18, Fa0/19, Fa0/20, Fa0/21
Fa0/22, Fa0/23, Fa0/24, Gi0/1
Gi0/2
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
S1#show vtp status
VTP Version : 2
Configuration Revision : 2
Maximum VLANs supported locally : 250
Number of existing VLANs : 7
VTP Operating Mode : Server

VTP Domain Name : Group1
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xB9 0x8C 0x14 0x31 0x5F 0x85 0x67 0xFC
Configuration last modified by 172.16.1.3 at 3-1-93 00:02:29
Local updater ID is 172.16.1.3 on interface Vl1 (lowest numbered VLAN interface found)
S1#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0001, VLAN0010
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001 0 0 0 3 3
VLAN0010 0 0 0 3 3
VLAN0020 1 0 0 2 3
---------------------- -------- --------- -------- ---------- ----------
3 vlans 1 0 0 8 9
S1#show version
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1, RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Tue 04-Mar-03 02:14 by yenanh
Image text-base: 0x80010000, data-base: 0x805A8000
ROM: Bootstrap program is CALHOUN boot loader
S1 uptime is 34 minutes
System returned to ROM by power-on
System image file is "flash:c2950-i6q4l2-mz.121-13.EA1.bin"
Appendix D: CCNA 3 Skills-Based Assessment Practice 493
cisco WS-C2950T-24 (RC32300) processor (revision K0) with 20839K bytes of memory
.
Processor board ID FOC0743Y1E3
Last reset from system-reset

494 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Running Enhanced Image
24 FastEthernet/IEEE 802.3 interface(s)
2 Gigabit Ethernet/IEEE 802.3 interface(s)
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:0E:38:5D:E3:80
Motherboard assembly number: 73-6114-09
Power supply part number: 34-0965-01
Motherboard serial number: FOC07430LSF
Power supply serial number: DAB0742EDCL
Model revision number: K0
Motherboard revision number: A0
Model number: WS-C2950T-24
System serial number: FOC0743Y1E3
Configuration register is 0xF
S2
S2#show run
Building configuration...
hostname S2
!
enable secret class
!
no ip domain-lookup
ip host S1 172.16.1.3
ip host R1 172.16.1.1
!
!
spanning-tree vlan 20 priority 24576
!
!------------------------------------------
!VTP and VLAN Configurations
!----------------------------------------vtp
mode client
vtp domain Group1
vtp password cisco
!------------------------------------------
!
interface FastEthernet0/1
shutdown
!
interface FastEthernet0/2
switchport mode trunk
!
interface FastEthernet0/3

switchport mode trunk
!
interface range FastEthernet0/4 - 6
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/7 - 9
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/10 - 24
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface Vlan1
ip address 172.16.1.4 255.255.255.0
no shutdown
!
ip default-gateway 172.16.1.1
ip http server
!
banner motd $
***********************************
!!!AUTHORIZE ACCESS ONLY!!!
***********************************
$
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
Appendix D: CCNA 3 Skills-Based Assessment Practice 495

496 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
logging synchronous
login
line vty 5 15
exec-timeout 0 0
password cisco
logging synchronous
login
end
S2#show vlan brief
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active Fa0/1, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
10 Accounting active Fa0/4, Fa0/5, Fa0/6
20 Marketing active Fa0/7, Fa0/8, Fa0/9
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
S2#show vtp status
VTP Version : 2
Configuration Revision : 2
Maximum VLANs supported locally : 64
Number of existing VLANs : 7
VTP Operating Mode : Client
VTP Domain Name : Group1
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0xB9 0x8C 0x14 0x31 0x5F 0x85 0x67 0xFC
Configuration last modified by 172.16.1.3 at 3-1-93 00:02:29
S2#show spanning-tree summary
Switch is in pvst mode
Root bridge for: VLAN0020
EtherChannel misconfiguration guard is enabled
Extended system ID is enabled
Portfast is disabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is disabled by default
Loopguard is disabled by default

UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is short
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001 1 0 0 1 2
VLAN0010 1 0 0 1 2
VLAN0020 0 0 0 2 2
---------------------- -------- --------- -------- ---------- ----------
3 vlans 2 0 0 4 6
S2#show version
Cisco Internetwork Operating System Software
IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(13)EA1, RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Tue 04-Mar-03 02:14 by yenanh
Image text-base: 0x80010000, data-base: 0x805A8000
ROM: Bootstrap program is CALHOUN boot loader
S2 uptime is 35 minutes
System returned to ROM by power-on
System image file is "flash:/c2950-i6q4l2-mz.121-13.EA1.bin"
cisco WS-C2950-24 (RC32300) processor (revision J0) with 20839K bytes of memory.
Processor board ID FHK0728W0XH
Last reset from system-reset
Running Standard Image
24 FastEthernet/IEEE 802.3 interface(s)
32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:0D:65:62:E3:80
Motherboard assembly number: 73-5781-11
Power supply part number: 34-0965-01
Motherboard serial number: FOC07280RA4
Power supply serial number: DAB07278PCM
Model revision number: J0
Motherboard revision number: A0
Model number: WS-C2950-24
System serial number: FHK0728W0XH
Configuration register is 0xF
S2#
Appendix D: CCNA 3 Skills-Based Assessment Practice 497

498 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
CCNA 3 Comprehensive Skills-Based Assessment
Table D-1 VLSM Addressing Scheme
Device Name Interface Address Subnet Mask
ISP Lo0 209.165.202.192 255.255.255.255
S0 209.165.201.1 255.255.255.252
CORE S0 209.165.201.2 255.255.255.252
E0 172.16.7.65 255.255.255.248
DIST-A Lo0 209.165.200.225 255.255.255.255
S0 172.16.7.81 255.255.255.252
E0 172.16.7.66 255.255.255.248
DIST-B Lo0 172.16.7.1 255.255.255.192
S0 172.16.7.85 255.255.255.252
E0 172.16.7.67 255.255.255.248
DIST-C S0 172.16.7.82 255.255.255.252
S1 172.16.7.86 255.255.255.252
F0.1 172.16.7.73 255.255.255.248
F0.10 172.16.0.1 255.255.252.0
F0.20 172.16.4.1 255.255.254.0
F0.30 172.16.6.1 255.255.255.0
ALSw-A VLAN 1 172.16.7.74 255.255.255.248
ALSw-B VLAN 1 172.16.7.75 255.255.255.248
Objectives
Demonstrate a comprehensive implementation of CCNA 3 skills by completing the following:
■ Design a VLSM addressing scheme to meet requirements
■ Configure OSPF, static, and default routing
■ Configure STP and port security
■ Configure VTP and VLANs
■ Verify your configuration and gather documentation
Scenario
You are the network administrator for a small corporation. You are planning a migration to a three-layer
hierarchical design using OSPF and VLANs. At the core layer, your router will provide access to the
Internet. At the distribution layer, you will use one router for access to your public Web servers (DIST-A),
one router for access to the enterprise server farm (DIST-B), and one router for routing VLANs (DIST-C).
At the access layer, you will trunk two switches with VLAN implementation. In addition, you will completely
redesign your addressing scheme using VLSM.

Design Considerations
You can use any five routers at your disposal. However, DIST-C must be a 1700 or 2600 series router that
will support routing VLANs. The server LANs off of ISP, DIST-A, and DIST-B can be simulated with
loopback interfaces.
Task 1: Lab Setup
Step 1. Cable the lab with available equipment in the configuration shown in Figure D-3.
Step 2. Label Figure D-3 with the appropriate interface names (such as S0, S0/0, E0, Fa0, and so on).
Step 3. Label serial interfaces with the appropriate DTE or DCE designation.
Task 2: Addressing Scheme
Appendix D: CCNA 3 Skills-Based Assessment Practice 499
Design an appropriate VLSM addressing scheme using the following method to assign subnets and interface
addresses. Maximize the number of host addresses at each level of subnetting.
Step 1. VLSM Level 1: Subnet the given address space 172.16.0.0/16 to provide enough addresses for
1000 hosts and assign subnet zero to VLAN 10.
Step 2. VLSM Level 2: Using subnet 1 left over from VLSM Level 1, subnet it to provide enough
addresses for 500 hosts and assign subnet 0 to VLAN 20.
Step 3. VLSM Level 3: Using subnet 1 left over from VLSM Level 2, subnet it to provide enough
addresses for 250 hosts and assign subnet 0 to VLAN 30.
Step 4. VLSM Level 4: Using subnet 1 left over from VLSM Level 3, subnet it to provide enough
addresses for 60 hosts and assign subnet 0 to the server farm.
Step 5. VLSM Level 5: Using subnet 1 left over from VLSM Level 4, subnet it to provide enough
addresses for three hosts. Assign subnet 0 to the CORE LAN (three hosts) and subnet 1 to
VLAN 1 (three hosts).
Step 6. VLSM Level 6: Using subnet 2 left over from VLSM Level 5, subnet it to provide enough
addresses for the remaining two WAN links. Assign subnet 0 to the WAN link between DIST-A
and DIST-C and subnet 1 to the WAN link between DIST-B and DIST-C.
Step 7. Fill in Table D-1 with your addressing design and label the topology with the assigned subnets.
Step 8. On the topology in Figure D-3, label each interface with the last two octets of the interface’s IP
address.

500 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Figure D-3 CCNA 3 Comprehensive Skills-Based Assessment (Answer)
Outside Public Web
Server:
209.165.202.129/32
Lo0
ISP
Private Address
Space
172.16.0.0/16
S0
.201.1/30
Task 3: Basic Router and Switch Configuration
Erase the stored configuration on all routers and switches and reload without saving changes. Configure
each with the following basic configurations:
■ Hostnames
■ Passwords
■ Host table
209.165.201.0/30
Interface designations will
depend on equipment used.
S0
.201.2/30
CORE
E0
.7.65/29
Lo0
E0 E0
.7.66/29 .7.67/29
Lo0
DIST-A S0
S0 DIST-B
OSPF
Server Farm
.7.85/30
.7.81/30
S0 S1
Inside Public Web
Server:
209.165.200.225/32
.7.82/30 .7.86/30
DIST-C
VLAN 1 .7.75/29
Fa0.1 .7.73/20
Fa0.10 0.1/22
Fa0.20 .4.1/23
Fa0.30 .6.1/24
VLAN 1 .7.74/29
ALSw-A 802.1Q Trunk
ALSw-B
VLAN 10 VLAN 20 VLAN 30 VLAN 10 VLAN 20 VLAN 30

■ Console line and Telnet lines
■ Interface addresses
Task 4: Configure OSPF, Static, and Default Routing
Step 1. Configure OSPF to advertise all inside routes:
■ The ISP router is not to participate in OSPF.
■ CORE is not to advertise the WAN link it shares with ISP.
■ Make sure DIST-A advertises the inside public web server.
Step 2. CORE must never be DR and DIST-A must always be DR.
Step 3. Configure a 5-second hello interval on OSPF enabled routers.
Step 4. Configure OSPF routers to use MD5 authentication.
Step 5. Set the LAN interface on DIST-C to passive so that OSPF updates do not get sent out to
ALSw-A.
Step 6. Configure CORE with a default static route to ISP.
Step 7. Advertise the default route to the rest of the inside routers.
Step 8. Configure ISP with a static route to the 172.16.0.0/16 address space and a static route to the
inside web server at 209.165.200.225/32.
Step 9. Verify that inside routers can now ping the outside web server.
Task 5: Spanning Tree and Port Security
Step 1. Configure ALSw-A to be the STP root bridge for VLAN 1 and VLAN 10.
Step 2. Configure ALSw-B to be the STP root bridge for VLAN 20 and VLAN 30.
Step 3. On both switches, configure the following on all access ports:
■ Set the ports to access mode.
■ Enable port security.
■ Enable the first MAC address to stick to the configuration.
■ Enable port shutdown if there is a security violation.
Step 4. If necessary for your switch platform, configure the switch trunk links to use IEEE 802.1Q.
Task 6: VLAN and VTP Configuration
Step 1. Configure ALSw-A to be the VTP server in the VTP domain CCNA3 with an appropriate
password.
Step 2. Configure ALSw-B to be a VTP client in the VTP domain CCNA3 with the correct password.
Step 3. Configure the VTP server with the following VLANs:
Appendix D: CCNA 3 Skills-Based Assessment Practice 501
■ VLAN 10: Finance
■ VLAN 20: Sales
■ VLAN 30: Purchasing
Step 4. Choose the ports to assign to each VLAN. It is not necessary to configure every port with a
VLAN.

502 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
Task 7: Verify Configurations and Gather Documentation
Step 1. You should now have full connectivity from any host on the network to any other host. Verify
end-to-end connectivity.
Step 2. When satisfied with your configurations, gather documentation for future reference. On all five
routers, capture the following output:
■ show run
■ show ip route
■ show ip interface brief
■ show ip ospf neighbors
Step 3. On the two switches, capture the following output:
ISP
■ show run
■ show vlan brief
■ show vtp status
ISP#show run
Building configuration...
hostname ISP
!
enable secret class
!
no ip domain-lookup
ip host DA 172.16.7.66 172.16.7.81
ip host DB 172.16.7.67 172.16.7.85
ip host DC 172.16.7.82 172.16.7.86
ip host CORE 209.165.201.2
ip host SA 172.16.7.74
ip host SB 172.16.7.75
!
interface Loopback0
description Simulated Outside Public Web Server
ip address 209.165.202.129 255.255.255.255
!
interface Serial0
description Link to Enterprise
ip address 200.20.2.1 255.255.255.252
clockrate 64000
no shutdown
!
ip route 209.165.200.225 255.255.255.255 Serial0
ip route 172.16.0.0 255.255.0.0 Serial0
!

!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
!
end
ISP#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0 unassigned YES unset administratively down down
Loopback0 209.165.202.129 YES manual up up
Serial0 200.20.2.1 YES manual up up
Serial1 unassigned YES unset administratively down down
ISP#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
209.165.201.0/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0
S 172.16.0.0/16 is directly connected, Serial0
209.165.200.0/32 is subnetted, 1 subnets
S 209.165.200.225 is directly connected, Serial0
209.165.202.0/32 is subnetted, 1 subnets
C 209.165.202.129 is directly connected, Loopback0
ISP#show version
Cisco Internetwork Operating System Software
Appendix D: CCNA 3 Skills-Based Assessment Practice 503

504 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
IOS (tm) 2500 Software (C2500-JS-L), Version 12.2(13b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Thu 20-Feb-03 14:09 by pwade
Image text-base: 0x0307C780, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0(10c), SOFTWARE
BOOTLDR: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE (fc1)
ISP uptime is 6 days, 2 hours, 55 minutes
System returned to ROM by reload
System image file is "flash:c2500-js-l.122-13b.bin"
cisco 2500 (68030) processor (revision N) with 14336K/2048K bytes of memory.
Processor board ID 18423267, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
TN3270 Emulation software.
1 Ethernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
CORE
CORE#show run
Building configuration...
hostname CORE
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host SB 172.16.7.75
ip host SA 172.16.7.74
ip host ISP 209.165.201.2
ip host DC 172.16.7.82 172.16.7.86
ip host DB 172.16.7.67 172.16.7.85
ip host DA 172.16.7.66 172.16.7.81
ip host WEB 209.165.202.129
!
interface Ethernet0
description Link to Distribution Layer

ip address 172.16.7.65 255.255.255.248
ip ospf priority 0
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
no shutdown
!
interface Serial0
description Link to ISP
ip address 209.165.201.2 255.255.255.252
no shutdown
!
router ospf 1
network 172.16.7.64 0.0.0.7 area 0
area 0 authentication message-digest
default-information originate
!
ip route 0.0.0.0 0.0.0.0 Serial0
!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
!
end
Appendix D: CCNA 3 Skills-Based Assessment Practice 505
CORE#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0 172.16.7.65 YES NVRAM up up
Serial0 209.165.201.2 YES NVRAM up up
Serial1 unassigned YES NVRAM administratively down down
CORE#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area

506 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
209.165.201.2/30 is subnetted, 1 subnets
C 209.165.201.0 is directly connected, Serial0
172.16.0.0/16 is variably subnetted, 8 subnets, 6 masks
O 172.16.4.0/23 [110/75] via 172.16.7.67, 1d21h, Ethernet0
[110/75] via 172.16.7.66, 1d21h, Ethernet0
O 172.16.7.1/32 [110/11] via 172.16.7.67, 1d21h, Ethernet0
O 172.16.6.0/24 [110/75] via 172.16.7.67, 1d21h, Ethernet0
[110/75] via 172.16.7.66, 1d21h, Ethernet0
O 172.16.0.0/22 [110/75] via 172.16.7.67, 1d21h, Ethernet0
[110/75] via 172.16.7.66, 1d21h, Ethernet0
O 172.16.7.80/30 [110/74] via 172.16.7.66, 1d21h, Ethernet0
O 172.16.7.84/30 [110/74] via 172.16.7.67, 1d21h, Ethernet0
O 172.16.7.72/29 [110/75] via 172.16.7.67, 1d21h, Ethernet0
[110/75] via 172.16.7.66, 1d21h, Ethernet0
C 172.16.7.64/29 is directly connected, Ethernet0
209.165.200.0/32 is subnetted, 1 subnets
O 209.165.200.255 [110/11] via 172.16.7.66, 1d21h, Ethernet0
S* 0.0.0.0/0 is directly connected, Serial0
CORE#show ip ospf 1
Routing Process "ospf 1" with ID 209.165.201.0
Supports only single TOS(TOS0) routes
Supports opaque LSA
It is an autonomous system boundary router
Redistributing External Routes from,
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 1. Checksum Sum 0x00C4B6
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 1
Area has no authentication
SPF algorithm executed 14 times

Area ranges are
Number of LSA 5. Checksum Sum 0x01DCA5
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
CORE#
CORE#show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-JS-L), Version 12.2(13b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Thu 20-Feb-03 14:09 by pwade
Image text-base: 0x0307C780, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0(10c), SOFTWARE
BOOTLDR: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE (fc1)
CORE uptime is 2 days, 34 minutes
System returned to ROM by power-on
System image file is "flash:/c2500-js-l.122-13b.bin"
cisco 2500 (68030) processor (revision N) with 14336K/2048K bytes of memory.
Processor board ID 18423246, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
TN3270 Emulation software.
1 Ethernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
DIST-A
DIST-A#show run
Building configuration...
hostname DIST-A
!
enable secret class
!
Appendix D: CCNA 3 Skills-Based Assessment Practice 507

508 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
no ip domain-lookup
ip host CORE 172.16.7.65
ip host WEB 209.165.202.129
ip host DB 172.16.7.67 172.16.7.85
ip host DC 172.16.7.82 172.16.7.86
ip host ISP 209.165.201.1
ip host SA 172.16.7.74
ip host SB 172.16.7.75
!
interface Loopback0
description Simulated Inside Public Web Server
ip address 145.46.47.48 255.255.255.255
!
interface Ethernet0
description Link to CORE and DIST-B
ip address 172.16.7.66 255.255.255.248
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
ip ospf priority 2
!
interface Serial0
description Link to DIST-C
ip address 172.16.7.81 255.255.255.252
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
clockrate 64000
!
router ospf 1
area 0 authentication message-digest
network 145.46.47.48 0.0.0.0 area 0
network 172.16.7.64 0.0.0.7 area 0
network 172.16.7.80 0.0.0.3 area 0
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0

password cisco
logging synchronous
login
!
end
DIST-A#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0 172.16.7.66 YES manual up up
Loopback0 145.46.47.48 YES manual up up
Serial0 172.16.7.81 YES manual up up
Serial1 unassigned YES unset administratively down down
DIST-A#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 172.16.7.65 to network 0.0.0.0
172.16.0.0/16 is variably subnetted, 8 subnets, 6 masks
O 172.16.4.0/23 [110/65] via 172.16.7.82, 1d21h, Serial0
O 172.16.7.1/32 [110/11] via 172.16.7.67, 1d21h, Ethernet0
O 172.16.6.0/24 [110/65] via 172.16.7.82, 1d21h, Serial0
O 172.16.0.0/22 [110/65] via 172.16.7.82, 1d21h, Serial0
C 172.16.7.80/30 is directly connected, Serial0
O 172.16.7.84/30 [110/74] via 172.16.7.67, 1d21h, Ethernet0
O 172.16.7.72/29 [110/65] via 172.16.7.82, 1d21h, Serial0
C 172.16.7.64/29 is directly connected, Ethernet0
209.165.200.0/32 is subnetted, 1 subnets
C 209.165.200.225 is directly connected, Loopback0
O*E2 0.0.0.0/0 [110/1] via 172.16.7.65, 1d21h, Ethernet0
DIST-A#show ip ospf neighbor
Appendix D: CCNA 3 Skills-Based Assessment Practice 509
Neighbor ID Pri State Dead Time Address Interface
209.165.201.2 0 FULL/DROTHER 00:00:35 172.16.7.65 Ethernet0
172.16.7.67 1 FULL/BDR 00:00:34 172.16.7.67 Ethernet0
172.16.7.82 1 FULL/ - 00:00:36 172.16.7.82 Serial0

510 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
DIST-A#show ip ospf 1
Routing Process "ospf 1" with ID 172.16.7.81
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 1. Checksum Sum 0x00C4B6
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 3
Area has no authentication
SPF algorithm executed 36 times
Area ranges are
Number of LSA 5. Checksum Sum 0x01DCA5
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
DIST-A#show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-JS-L), Version 12.2(13b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Thu 20-Feb-03 14:09 by pwade
Image text-base: 0x0307C780, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0(10c), SOFTWARE
BOOTLDR: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c), RELEASE SOFTWARE (fc1)
DIST-A uptime is 6 days, 3 hours, 3 minutes
System returned to ROM by reload
System image file is "flash:/c2500-js-l.122-13b.bin"
cisco 2500 (68030) processor (revision N) with 14336K/2048K bytes of memory.
Processor board ID 18424578, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
TN3270 Emulation software.
1 Ethernet/IEEE 802.3 interface(s)
2 Serial network interface(s)

32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
DIST-B
DIST-B#show run
Building configuration...
hostname DIST-B
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host CORE 172.16.7.65
ip host DC 172.16.7.82 172.16.7.86
ip host WEB 209.165.202.129
ip host DA 172.16.7.66 172.16.7.81
ip host ISP 209.165.201.1
ip host SA 172.16.7.74
ip host SB 172.16.7.75
!
!
interface Loopback0
description Link to Simulated Enterprise Server Farm
ip address 172.16.7.1 255.255.255.192
!
interface Ethernet0
description Link to CORE and DIST-A
ip address 172.16.7.67 255.255.255.248
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
no shutdown
!
interface Serial0
description Link to DIST-C
ip address 172.16.7.85 255.255.255.252
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
no shutdown
!
router ospf 1
area 0 authentication message-digest
network 172.16.7.0 0.0.0.63 area 0
Appendix D: CCNA 3 Skills-Based Assessment Practice 511

512 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
network 172.16.7.64 0.0.0.7 area 0
network 172.16.7.84 0.0.0.3 area 0
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
!
end
DIST-B#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0 172.16.7.67 YES manual up up
Ethernet1 unassigned YES unset administratively down down
Loopback0 172.16.7.1 YES manual up up
Serial0 172.16.7.85 YES manual up up
Serial1 unassigned YES unset administratively down down
DIST-B#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 172.16.7.65 to network 0.0.0.0
172.16.0.0/16 is variably subnetted, 8 subnets, 6 masks
O 172.16.4.0/23 [110/65] via 172.16.7.86, 1d21h, Serial0
O 172.16.6.0/24 [110/65] via 172.16.7.86, 1d21h, Serial0
C 172.16.7.0/26 is directly connected, Loopback0
O 172.16.0.0/22 [110/65] via 172.16.7.86, 1d21h, Serial0
O 172.16.7.80/30 [110/74] via 172.16.7.66, 1d21h, Ethernet0

C 172.16.7.84/30 is directly connected, Serial0
O 172.16.7.72/29 [110/65] via 172.16.7.86, 1d21h, Serial0
C 172.16.7.64/29 is directly connected, Ethernet0
209.165.200.0/32 is subnetted, 1 subnets
O 209.165.200.225 [110/11] via 172.16.7.66, 1d21h, Ethernet0
O*E2 0.0.0.0/0 [110/1] via 172.16.7.65, 1d21h, Ethernet0
DIST-B#show ip ospf neighbor
Appendix D: CCNA 3 Skills-Based Assessment Practice 513
Neighbor ID Pri State Dead Time Address Interface
172.16.7.82 1 FULL/ - 00:00:39 172.16.7.86 Serial0
200.20.2.2 0 FULL/DROTHER 00:00:38 172.16.7.65 Ethernet0
172.16.7.81 2 FULL/DR 00:00:35 172.16.7.66 Ethernet0
DIST-B# show ip ospf 1
Routing Process "ospf 1" with ID 172.16.7.67
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
Number of external LSA 1. Checksum Sum 0x00C4B6
Number of opaque AS LSA 0. Checksum Sum 0x000000
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 3
Area has no authentication
SPF algorithm executed 36 times
Area ranges are
Number of LSA 5. Checksum Sum 0x01DCA5
Number of opaque link LSA 0. Checksum Sum 0x000000
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
DIST-B#show version
Cisco Internetwork Operating System Software
IOS (tm) 2500 Software (C2500-JS-L), Version 12.2(13b), RELEASE SOFTWARE (fc1)
Copyright (c) 1986-2003 by cisco Systems, Inc.
Compiled Thu 20-Feb-03 14:09 by pwade
Image text-base: 0x0307C780, data-base: 0x00001000
ROM: System Bootstrap, Version 11.0(10c)XB2, PLATFORM SPECIFIC RELEASE SOFTWARE (fc1)

514 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
BOOTLDR: 3000 Bootstrap Software (IGS-BOOT-R), Version 11.0(10c)XB2, PLATFORM SPECIFIC
RELEASE SOFTWARE (fc1)
DIST-B uptime is 6 days, 2 hours, 57 minutes
System returned to ROM by reload
System image file is "flash:c2500-js-l.122-13b.bin"
cisco 2500 (68030) processor (revision L) with 14336K/2048K bytes of memory.
Processor board ID 19482472, with hardware revision 00000000
Bridging software.
X.25 software, Version 3.0.0.
SuperLAT software (copyright 1990 by Meridian Technology Corp).
TN3270 Emulation software.
2 Ethernet/IEEE 802.3 interface(s)
2 Serial network interface(s)
32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read ONLY)
Configuration register is 0x2102
DIST-C
DIST-C#show run
Building configuration...
hostname DIST-C
!
enable secret class
!
ip subnet-zero
no ip domain-lookup
ip host CORE 172.16.7.65
ip host WEB 183.84.85.86
ip host DB 172.16.7.85 172.16.7.67
ip host DA 172.16.7.81 172.16.7.66
ip host ISP 200.20.2.1
ip host SA 172.16.7.74
ip host SB 172.16.7.75
!
!------------------------------------------------
!Although DHCP is not taught until Module 1
!in CCNA4, it is useful in this Super Lab.
!So the configuration is provided for instructors
!----------------------------------------------ip
dhcp excluded-address 172.16.0.1 172.16.0.10
ip dhcp excluded-address 172.16.4.1 172.16.4.10

ip dhcp excluded-address 172.16.6.1 172.16.6.10
!
ip dhcp pool VLAN10
network 172.16.0.0 255.255.252.0
default-router 172.16.0.1
!
ip dhcp pool VLAN20
network 172.16.4.0 255.255.254.0
default-router 172.16.4.1
!
ip dhcp pool VLAN30
network 172.16.6.0 255.255.255.0
default-router 172.16.6.1
!------------------------------------------------
!
interface FastEthernet0
no shutdown
!
interface FastEthernet0.1
description Management VLAN 1
encapsulation dot1Q 1 native
ip address 172.16.7.73 255.255.255.248
!
interface FastEthernet0.10
description FINANCE subnet VLAN 10
encapsulation dot1Q 10
ip address 172.16.0.1 255.255.252.0
!
interface FastEthernet0.20
description SALES subnet VLAN 20
encapsulation dot1Q 20
ip address 172.16.4.1 255.255.254.0
ip access-group SALES_TRAFFIC in
!
interface FastEthernet0.30
description PURCHASING subnet VLAN 30
encapsulation dot1Q 30
ip address 172.16.6.1 255.255.255.0
ip access-group PURCHASING_TRAFFIC in
!
interface Serial0
description Link to DIST-B
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
ip address 172.16.7.82 255.255.255.252
no shutdown
Appendix D: CCNA 3 Skills-Based Assessment Practice 515

516 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
!
interface Serial1
description Link to DIST-A
ip ospf message-digest-key 1 md5 allrouters
ip ospf hello-interval 5
ip address 172.16.7.86 255.255.255.252
clock rate 64000
no shutdown
!
router ospf 1
area 0 authentication message-digest
network 172.16.0.0 0.0.3.255 area 0
network 172.16.4.0 0.0.0.1 area 0
network 172.16.6.0 0.0.0.255 area 0
network 172.16.7.72 0.0.0.7 area 0
network 172.16.7.80 0.0.0.3 area 0
network 172.16.7.84 0.0.0.3 area 0
passive-interface FastEthernet 0
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line aux 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
!
no scheduler allocate
end
DIST-C#show ip interface brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0 unassigned YES unset up up
FastEthernet0.1 172.16.7.73 YES manual up up
FastEthernet0.10 172.16.0.1 YES manual up up
FastEthernet0.20 172.16.4.1 YES manual up up

FastEthernet0.30 172.16.6.1 YES manual up up
Serial0 172.16.7.82 YES manual up up
Serial1 172.16.7.86 YES manual up up
DIST-C#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 172.16.7.85 to network 0.0.0.0
Appendix D: CCNA 3 Skills-Based Assessment Practice 517
172.16.0.0/16 is variably subnetted, 8 subnets, 6 masks
C 172.16.4.0/23 is directly connected, FastEthernet0.20
C 172.16.6.0/24 is directly connected, FastEthernet0.30
O 172.16.7.1/32 [110/782] via 172.16.7.85, 1d21h, Serial1
C 172.16.0.0/22 is directly connected, FastEthernet0.10
C 172.16.7.80/30 is directly connected, Serial0
C 172.16.7.84/30 is directly connected, Serial1
C 172.16.7.72/29 is directly connected, FastEthernet0.1
O 172.16.7.64/29 [110/791] via 172.16.7.81, 1d21h, Serial0
[110/791] via 172.16.7.85, 1d21h, Serial1
209.165.200.0/32 is subnetted, 1 subnets
O 209.165.200.225 [110/782] via 172.16.7.81, 1d21h, Serial0
O*E2 0.0.0.0/0 [110/1] via 172.16.7.85, 1d21h, Serial1
[110/1] via 172.16.7.81, 1d21h, Serial0
DIST-C#show ip ospf 1
Routing Process "ospf 1" with ID 172.16.7.82
Supports only single TOS(TOS0) routes
Supports opaque LSA
SPF schedule delay 5 secs, Hold time between two SPFs 10 secs
Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Number of external LSA 1. Checksum Sum 0xC4B6
Number of opaque AS LSA 0. Checksum Sum 0x0
Number of DCbitless external and opaque AS LSA 0
Number of DoNotAge external and opaque AS LSA 0
Number of areas in this router is 1. 1 normal 0 stub 0 nssa

518 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
External flood list length 0
Area BACKBONE(0)
Number of interfaces in this area is 6
Area has no authentication
SPF algorithm executed 26 times
Area ranges are
Number of LSA 5. Checksum Sum 0x1DCA5
Number of opaque link LSA 0. Checksum Sum 0x0
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
DIST-C#show ip ospf neighbors
Neighbor ID Pri State Dead Time Address Interface
172.16.7.67 1 FULL/ - 00:00:31 172.16.7.85 Serial1
172.16.7.81 1 FULL/ - 00:00:30 172.16.7.81 Serial0
DIST-C#show version
Cisco Internetwork Operating System Software
IOS (tm) C1700 Software (C1700-Y-M), Version 12.2(4)YB, EARLY DEPLOYMENT RELEASE SOFT-
WARE (fc1)
Synched to technology version 12.2(6.8)T2
TAC Support: http://www.cisco.com/tac
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Fri 15-Mar-02 20:32 by ealyon
Image text-base: 0x80008124, data-base: 0x807D8744
ROM: System Bootstrap, Version 12.2(7r)XM1, RELEASE SOFTWARE (fc1)
ROM: C1700 Software (C1700-Y-M), Version 12.2(4)YB, EARLY DEPLOYMENT RELEASE SOFTWARE
(fc1)
DIST-C uptime is 6 days, 31 minutes
System returned to ROM by power-on
System image file is "flash:c1700-y-mz.122-4.YB.bin"
cisco 1721 (MPC860P) processor (revision 0x100) with 29492K/3276K bytes of memory.
Processor board ID FOC07190RE7 (3108345534), with hardware revision 0000
MPC860P processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
1 FastEthernet/IEEE 802.3 interface(s)
2 Low-speed serial(sync/async) network interface(s)

32K bytes of non-volatile configuration memory.
16384K bytes of processor board System flash (Read/Write)
Configuration register is 0x2102
ALSw-A
ALSw-A#show run
Building configuration...
hostname ALSw-A
!
enable secret class
!
no ip domain-lookup
ip host CORE 172.16.7.65
ip host WEB 209.165.202.129
ip host DC 172.16.7.73
ip host DB 172.16.7.85 172.16.7.67
ip host DA 172.16.7.81 172.16.7.66
ip host ISP 209.165.201.1
ip host SB 172.16.7.75
!
!
spanning-tree vlan 1 priority 4096
spanning-tree vlan 10 priority 24576
!
!
interface FastEthernet0/1
switchport mode trunk
!
interface FastEthernet0/2
switchport mode trunk
!
interface range FastEthernet0/3 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
Appendix D: CCNA 3 Skills-Based Assessment Practice 519

520 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface Vlan1
ip address 172.16.7.74 255.255.255.248
no shutdown
!
ip default-gateway 172.16.7.73
!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 5 15
exec-timeout 0 0
password cisco
logging synchronous
login
!
end
ALSw-A#show vlan brief
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active
10 FINANCE active Fa0/3, Fa0/4, Fa0/5, Fa0/6
Fa0/7, Fa0/8
20 SALES active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16

30 PURCHASING active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
ALSw-A#show vtp status
VTP Version : 2
Configuration Revision : 1
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Server
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x3E 0x12 0x21 0x3C 0x7D 0x09 0xAB 0x97
Configuration last modified by 172.16.7.74 at 3-1-93 04:07:07
Local updater ID is 172.16.7.74 on interface Vl1 (lowest numbered VLAN interface found)
ALSw-B
ALSw-B#show run
Building configuration...
hostname ALSw-B
!
enable secret class
!
no ip domain-lookup
ip host CORE 172.16.7.65
ip host SA 172.16.7.74
ip host ISP 209.165.201.1
ip host DA 172.16.7.81 172.16.7.66
ip host DB 172.16.7.85 172.16.7.67
ip host DC 172.16.7.73
ip host WEB 209.165.202.129
!
!
spanning-tree vlan 20 priority 4096
spanning-tree vlan 30 priority 24576
!
!
Appendix D: CCNA 3 Skills-Based Assessment Practice 521

522 Switching Basics and Intermediate Routing CCNA 3 Labs and Study Guide
interface FastEthernet0/1
shutdown
!
interface FastEthernet0/2
switchport mode trunk
!
interface range FastEthernet0/3 - 8
switchport access vlan 10
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/9 - 16
switchport access vlan 20
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
interface range FastEthernet0/17 - 24
switchport access vlan 30
switchport mode access
switchport port-security
switchport port-security mac-address sticky
switchport port-security maximum 1
switchport port-security violation shutdown
!
!
interface Vlan1
ip address 172.16.7.75 255.255.255.248
no shutdwon
!
ip default-gateway 172.16.7.73
!
!
line con 0
exec-timeout 0 0
password cisco
logging synchronous
login
line vty 0 4
exec-timeout 0 0
password cisco

logging synchronous
login
line vty 5 15
exec-timeout 0 0
password cisco
logging synchronous
login
end
ALSw-B#show vlan brief
Appendix D: CCNA 3 Skills-Based Assessment Practice 523
VLAN Name Status Ports
---- -------------------------------- --------- -------------------------------
1 default active
10 FINANCE active Fa0/2, Fa0/3, Fa0/4, Fa0/5
Fa0/6, Fa0/7, Fa0/8
20 SALES active Fa0/9, Fa0/10, Fa0/11, Fa0/12
Fa0/13, Fa0/14, Fa0/15, Fa0/16
30 PURCHASING active Fa0/17, Fa0/18, Fa0/19, Fa0/20
Fa0/21, Fa0/22, Fa0/23, Fa0/24
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active
ALSw-B#show vtp status
VTP Version : 2
Configuration Revision : 1
Maximum VLANs supported locally : 64
Number of existing VLANs : 8
VTP Operating Mode : Client
VTP Domain Name : CCNA3
VTP Pruning Mode : Disabled
VTP V2 Mode : Disabled
VTP Traps Generation : Disabled
MD5 digest : 0x3E 0x12 0x21 0x3C 0x7D 0x09 0xAB 0x97
Configuration last modified by 172.16.7.74 at 3-1-93 04:07:07