This happens for me too since upgrading to feisty (kernel 2.6.20-8), on a machine with an RL-8139 onboard NIC. The one major difference is that the behaviour always happens and occurs immediately on boot up.
-- Strange network behavior https://launchpad.net/bugs/85520 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
