CCNA Complete Guide 2nd Edition.pdf - Cisco Learning Home

- The ip classless global configuration command is important when using default routing. It is
enabled by default in Cisco IOS release 12.0 and later. Default routing and classless routing are
discussed further in Chapter 17 – Classful and Classless Routing and MISC TCP/IP Topics.
- Multiple routes can be configured and flagged as candidate default routes. The candidate default
route with the lowest metric will be selected as the default route.
RIP Configuration
- The main command when configuring RIP and IGRP is the network {classful-network-addr}
router subcommand. It matches one or more interfaces on a router and causes the router to
perform 3 tasks on the matched interfaces:
i) Broadcast routing updates out the matched interfaces.
ii) Listen and process incoming routing updates from the matched interfaces.
iii) Include the subnet of the matched interfaces in the routing updates to other routers.
- RIP configuration on RT1:
RT1(config)#no ip route 0.0.0.0 0.0.0.0 192.168.2.2
RT1(config)#router rip
RT1(config-router)#network 192.168.1.0
RT1(config-router)#network 192.168.2.0
RT1(config-router)#^Z
RT1#
- RIP configuration on RT2:
RT2(config)#no ip route 192.168.1.0 255.255.255.0 192.168.2.1
RT2(config)#no ip route 192.168.5.0 255.255.255.0 192.168.4.2
RT2(config)#router rip
RT2(config-router)#network 192.168.2.0
RT2(config-router)#network 192.168.3.0
RT2(config-router)#network 192.168.4.0
RT2(config-router)#^Z
RT2#
- RIP configuration on RT3:
RT3(config)#no ip route 192.168.1.0 255.255.255.0 192.168.4.1
RT3(config)#no ip route 192.168.2.0 255.255.255.0 192.168.4.1
RT3(config)#no ip route 192.168.3.0 255.255.255.0 192.168.4.1
RT3(config)#router rip
RT3(config-router)#network 192.168.4.0
RT3(config-router)#network 192.168.5.0
RT3(config-router)#^Z
RT3#
- Note: Remember that the administrative distances of static routes and RIP routers are 1 and 120
respectively, hence static routes must to be removed in order to use the routes learnt via RIP.
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Copyright © 2008 Yap Chin Hoong
yapchinhoong@hotmail.com