Network stopped working about a month ago. I installed ubuntu again, and network worked fine, and I turned off updates to keep things stable. Now network stopped working again. No changes had been made to it.
I put in the ubuntu install cd, and network works fine off of it. I did not reinstall again.

ifconfig shows eth0 with correct ip address, but 0 RX/TX packets.

Cant ping anything from it, and cant ping to it from other computers.

I'd really rather not reinstall yet again, any ideas on how I should go about diagnosing this problem?

Ubuntu 2.6.35-28-generic-pae #49-Ubuntu SMP Tue Mar 1 14:58:06 UTC 2011 i686 GNU/Linux

Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03)

What happens when you restart networking?

It works

So, must be some timing problem during startup?

Kind of a pain since I only use that machine remotely, but I suppose I can make sure I only reboot it when physically present.

Thanks for your help.