Cisco IOS Cookbook, 2nd Edition

Using Static Routing

Problem

You want to configure a static route.

Solution

You can configure a static route with the ip route command, as follows:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#ip route 10.35.15.5 255.255.255.255 Ethernet0
Router(config)#end 
Router#

You can also configure a static route to point to a particular next hop router:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#interface Serial0
Router(config-if)#ip address 10.35.6.2 255.255.255.0  
Router(config-if)#exit
Router(config)#ip route 172.16.0.0 255.255.0.0 10.35.6.1 2
Router(config)#end
Router#

If you want to ensure a route remains in place even if the next-hop IP address becomes unreachable, or the interface goes down, you can use the permanent keyword:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#ip route 10.35.15.5 255.255.255.255 Ethernet0 permanent
Router(config)#ip route 172.16.0.0 255.255.0.0 10.35.6.1 2 permanent
Router(config)#end
Router#

You can also manually configure routing tags that use static routes by using the tag keyword:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#ip route 172.16.0.0 255.255.0.0 10.35.6.1 2 tag 36291
Router(config)#end
Router#

Discussion

The first version sends all packets destined to the single host 10.35.15.5 out through the Ethernet0 interface. In this case, ...