I wrote this draft quite ago . Just stumbled upon on it in the drafts section, may this would help someone
Change IP address
You can change ip address using ifconfig command itself. To set IP address 192.168.1.5, enter command:
# ifconfig eth0 192.168.1.5 netmask 255.255.255.0 up
# ifconfig eth0
To make permanent changes to IP address you need to edit configuration file according to your Linux distribution.
Here are some detailed posts: