Cisco IOS Cookbook, 2nd Edition

Disabling RIP on an Interface

Problem

You want to prevent an interface from participating in RIP.

Solution

You can prevent an interface from participating in RIP with the following set of commands:

Router1#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router1(config)#access-list 12 deny any
Router1(config)#router rip 
Router1(config-router)#passive-interface FastEthernet0/1
Router1(config-router)#distribute-list 12 in FastEthernet0/1
Router1(config-router)#end
Router1#

Discussion

As we discussed in Recipe 6.1, you enable RIP on an interface with a network command. But because RIP expects any networks you specify this way to follow address class rules, it is quite easy to inadvertently enable RIP on an interface that you don’t want to use this protocol.

There are two important reasons that might lead you to disable RIP on a particular interface. First, if you are already running another protocol on a particular interface, then the additional RIP traffic could consume important bandwidth resources. Second, there may be devices on a particular network segment that you do not trust. In this case you want to make sure that you don’t let them distribute routing information into your network. This is particularly important because some Unix workstations run RIP by default, but the administrators rarely devote much attention to making sure that any local static routes have the correct metric values. It is possible for one misconfigured workstation to completely ...