Cisco IOS Cookbook, 2nd Edition

Finding an IP Route

Problem

You want to find a particular route in your router’s routing tables.

Solution

The EXEC level command to look at the entire IP routing table is:

Router>show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
       U - per-user static route, o - ODR

Gateway of last resort is 172.25.1.1 to network 0.0.0.0

     192.168.17.0/27 is subnetted, 1 subnets
C       192.168.17.0 is directly connected, Loopback1
     172.16.0.0/30 is subnetted, 1 subnets
C       172.16.1.0 is directly connected, Async1
     172.25.0.0/16 is variably subnetted, 6 subnets, 3 masks
C       172.25.25.0/30 is directly connected, Tunnel0
C       172.25.1.0/24 is directly connected, Ethernet0
C       172.25.9.0/24 is directly connected, Ethernet1
C       172.25.10.1/32 is directly connected, Loopback0
O       172.25.100.1/32 [110/11] via 172.25.9.2, 4d09h, Ethernet1
O IA    172.25.100.0/24 [110/11] via 172.25.1.1, 2d11h, Ethernet0
     192.168.1.0/32 is subnetted, 1 subnets
S       192.168.1.1 [1/0] via 172.25.1.4
O*E1 0.0.0.0/0 [110/11] via 172.25.1.1, 1d07h, Ethernet0

You can also find the route to a particular device, such as 172.25.100.15:

Router>show ip route 172.25.100.15 Routing entry for 172.25.100.0/24 Known via "ospf 55", distance 110, metric 11, type inter area Redistributing ...