This page will explain how to renew your DHCP address when using Linux.

Usage

Type the following command from the terminal prompt. If you are using a distro other than Ubuntu, make sure that your user account has sudo permissions, otherwise you might have to use su to switch to root before entering the command.

sudo dhclient -r

Output:

Internet Systems Consortium DHCP Client V3.0.5
Copyright 2004-2006 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

Listening on LPF/eth0/00:0c:29:3d:6e:71
Sending on   LPF/eth0/00:0c:29:3d:6e:71
Sending on   Socket/fallback

You can restart networking if you are having problems by using the following command:

sudo /etc/init.d/networking restart