This document describes configuring default routing on two routers, Router1 and Router2. On Router1, the default route is configured to point to the IP address 172.16.1.2 using the command "ip route 0.0.0.0 0.0.0.0 172.16.1.2". On Router2, the default route is configured to point to the IP address 172.16.1.1 using the command "ip route 0.0.0.0 0.0.0.0 172.16.1.1". The show ip route command confirms that on each router the gateway of last resort is set according to the configured default route.

1. Default Routing
WWW.TCPIPGURU.COM

3. Default routing: On Router1
R1#config t
Enter configuration commands, one per line. End with CNTL/Z.
R1(config)#ip route 0.0.0.0 0.0.0.0 172.16.1.2
R1(config)#exit
R1#
*Mar 1 08:08:44.487: %SYS-5-CONFIG_I: Configured from console by
console

4. R1#show ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 172.16.1.2 to network 0.0.0.0
C 172.16.0.0/16 is directly connected, Serial0/0
C 192.168.1.0/24 is directly connected, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 172.16.1.2

5. Default routing: On Router2
R2#config t
Enter configuration commands, one per line. End
with CNTL/Z.
R2(config)#ip route 0.0.0.0 0.0.0.0
172.16.1.1
R2(config)#exit

6. R2#show ip route
*Mar 1 10:02:54.679: %SYS-5-CONFIG_I: Configured from console by consol
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route
Gateway of last resort is 172.16.1.1 to network 0.0.0.0
C 172.16.0.0/16 is directly connected, Serial0/0
C 192.168.2.0/24 is directly connected, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 172.16.1.1