Introduction to Routing

 R1#show ip route

The router will check the entire routing table for the best possible match, also known as the longest match. The route that has the most bits that match the destination will be route used to forward the packet. 


R1(config)#ip route 0.0.0.0

R1(config)#ip route 0.0.0.0 0.0.0.0 20.1.1.2


R3#cont t

R3(config)#int loopback 3

RE(config-if)#ip address 3.3.3.3 255.255.255.0

R3#show int loopback 3

R3#ping

Repeat count [5]:100000

To get out press control shift +6 twice

R2#traceroute 2.2.2.2

If you see * the packet is not leaving the router. 

R3#debug ip packet

R3#no debug ip packet

R3#u all

R3#show ip route

R3#config t

R3(config)#ip route 0.0.0.0 0.0.0.0 172.12.123.1

R3#show ip route

S* means static

R3#show debug

R3#debug ip packet

R1(config)#ip route 2.2.2.0 255.255.2550 172.12.123.2





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