Cisco Systems CCNA 2 Preventing routing updates through an interface, Load Balancing with RIP

219.17.100.0 in 1 hops

199.6.13.0in 1 hops

210.93.105.0 in 3 hops

Other commands that can be used to troubleshoot RIP update issues include the following:

•show ip rip database

•show ip protocols

•show ip route

•debug ip rip

•show ip interface brief

7.2.7Preventing routing updates through an interface

The passive interface command prevents routing updates from being sent out a particular interface. In the graphic, Router Z interface Fa0/0 is not allowed to send router updates to Router A. This may be implemented for a variety of reasons. One reason might be that the administrator of Router Z does not want information about the internal network to be sent out to other routers. If Router Z is a stub network, the administrator of Router A may prevent routing updates from being sent to Router Z since there is one way in and one way out. Students must understand that routes will still be learned through this interface. They also need to know that the network that this interface is connected to is advertised if a network statement is configured for that network.

7.2.8 Load Balancing with RIP

Load balancing is the process of routing packets over multiple equal-cost paths to increase throughput. RIP can load balance over as many as six equal-cost paths, although four is the default. Packets are sent “round robin” over the equal-cost paths, this means that the equal- cost paths are used in turn. Since the metric for RIP is hop count, equal-cost paths indicate that a network can be reached through multiple paths that have the same hop count.

85 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Module 7 Copyright ♥ 2004, Cisco Systems, Inc.