28.06.2014 Views

Discussion

Discussion

Discussion

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

TLVs:<br />

Area address: 49.0030 (3)<br />

Speaks: IP<br />

Speaks: IPv6<br />

IP router id: 192.168.18.1<br />

IP address: 192.168.18.1<br />

Hostname: RouterH<br />

IP prefix: 10.0.24.0/24, Internal, Metric: default 10, Up<br />

IP prefix: 10.0.1.0/24, Internal, Metric: default 10, Up<br />

IP extended prefix: 10.0.24.0/24 metric 10 up<br />

IP extended prefix: 10.0.1.0/24 metric 10 up<br />

IS neighbor: RouterG.02, Internal, Metric: default 10<br />

IS extended neighbor: RouterG.02, Metric: default 10<br />

IP address: 10.0.1.1<br />

No queued transmissions<br />

The first section of the output shows the entries (IS-IS neighbors and IP prefixes) in<br />

the link-state database:<br />

RouterH.00-00 Sequence: 0x62, Checksum: 0xa116, Lifetime: 1121 secs<br />

IS neighbor: RouterG.02 Metric: 10<br />

IP prefix: 10.0.1.0/24 Metric: 10 Internal Up<br />

IP prefix: 10.0.24.0/24 Metric: 10 Internal Up<br />

RouterG has one IS-IS neighbor, RouterH, and the metric to reach this neighbor is 10<br />

(the default). RouterG has learned two prefixes, both from a Level 1 (internal) IS-IS<br />

area, and both prefixes have the default metric cost of 10. Any routes learned from<br />

outside the area would be marked External.<br />

The remaining three sections correspond to portions of the LSP. The Header section<br />

shows the packet length, the router ID (which is the address configured on the lo0<br />

interface), and various timer information. The Packet section shows the PDU length,<br />

remaining lifetime, checksum, sequence number, and other information. The TLV<br />

section shows the TLV information carried in the LSP. The first line shows TLV 1,<br />

the address of the area in which the router is located:<br />

Area address: 49.0030 (3)<br />

RouterH is in area 49.0030. The next two lines list the protocols that RouterH supports<br />

(TLV 129):<br />

Speaks: IP<br />

Speaks: IPv6<br />

The router is running both IPv4 and IPv6. Next, you see two router IDs:<br />

IP router id: 192.168.18.1<br />

IP address: 192.168.18.1<br />

The first line corresponds to TLV 134, the traffic-engineering router ID (defined in RFC<br />

3784), and the second is TLV 132, which is defined as the interface address. In the<br />

JUNOS IS-IS implementation, the IP address field shows the configured router ID, not<br />

all interface addresses. The sixth line shows the router’s dynamic (symbolic) hostname:<br />

Hostname: RouterH<br />

358 | Chapter 11: IS-IS<br />

This is the Title of the Book, eMatter Edition<br />

Copyright © 2008 O’Reilly & Associates, Inc. All rights reserved.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!