IP release in Ubuntu

I have recently been having problems in Ubuntu with it having an extreme preference to connect to my wireless network rather than connect via eth0. I found out that the command to release the IP address an


$ sudo dhclient -r


To renew the address its the same command but without the r


$ sudo dhclient -r

If things get really bad, you can always restart the networking service.

$ /etc/init.d/networking restart