Trouble with Xbox

[InsaniaEx]

I am using a netbook (ubuntu OS) as a router for my XBox so it can connect to XBox live. I set up so auto eth0 shares with other computers. But when I try to connect to live, it stops on the XBox 360 -> Network part of the test. In more info, it tells me:
Can't obtain an IP address from your router or modem.

It was working with a Windows 7 laptop just minutes before, but I don't no longer can use this one.

Thanks for any help.

[InsaniaEx]

I really need the help now.

[-humanaut-]

So are you using wireless to connect the netbook and trying to route it with auto-eth0 (hardwired) to the xbox?

[InsaniaEx]

http://www.linuxquestions.org/linux/...a_wireless_LAN

By following this tutorial, I got past the problem of connecting to network, but now I have a problem from network to internet, more info tells me problem with DNS, and i realised I had not changed the Secondary DNS. I am not exactly sure what to change it to.

[InsaniaEx]

Again, any help will be appreciated.

[InsaniaEx]

Seriously guys, I am pretty much begging here.