IP address Command on CISCO Router/Switch


IP address


This command is used to set IP addresses on an interface.


R1(config)#ip address <IP address> <subnet mask> <secondary>


<IP address>IP address for the interface
<subnet mask>IP address for the interface
<secondary>Sets the IP address as a secondary IP address, you can have many secondary IP addresses on an interface if required. Though some routing protocols do not function properly with secondary addresses.


In this example, we set the ip address of int fa0/0 on R2.

R2(config)#int fa0/0
R2(config-if)#ip add
R2(config-if)#do sh ip int brief
Interface IP-Address OK? Method Status Protocol
FastEthernet0/0 YES NVRAM up up

Next, to test it out, we do a quick ping to the new ip address.

R2(config-if)#ip add secondary

R2(config-if)#do ping

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms