Cisco IOS Cookbook, 2nd Edition

Changing Administrative Distances

Problem

You want to change the administrative distance for an external network.

Solution

You use the distance command to adjust the administrative distance for a particular routing protocol. The precise syntax depends on the routing protocol. This example uses RIP:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#router rip
Router(config-route)#network 192.168.15.0
Router(config-route)#distance 15 192.168.15.1 0.0.0.0
Router(config-route)#distance 200 192.168.15.0 0.0.0.255
Router(config-route)#distance 255
Router(config-route)#end
Router#

For EIGRP, you can specify the distance for routes learned from both internal and external neighbors:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#router eigrp 111
Router(config-route)#network 192.168.16.0
Router(config-route)#distance eigrp 55 200
Router(config-route)#end
Router#

With OSPF, you can also control the distance, depending on whether the neighboring router is in the same area:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#router ospf 66
Router(config-route)#distance ospf inter-area 115
Router(config-route)#distance ospf intra-area 105
Router(config-route)#distance ospf external 125
Router(config-route)#end
Router#

And you can configure BGP distances for internal, external, and local routes:

Router#configure terminal Enter configuration commands, ...