Set an IP address on interface FastEhternet 0/0:
2811a>enable
2811a#configure terminal
2811a(config)#interface FastEthernet 0/0
2811a(config-if)#ip address 172.16.0.2 255.255.255.0
2811a(config-if)#description Uplink to Firewall
2811a(config-if)#end
2811a#
*Jan 8 15:06:37.187: %SYS-5-CONFIG_I: Configured from console by Console2811a#
After the command end, the console displays a SYS-5-CONFIG_I message.