Comment 10 for bug 768506

Excerpts from Ernst's message of Wed May 18 21:01:31 UTC 2011:
> I only use a wired network (although a wireless network is available, but I
> do not connect to that wireless network), so that's not the cause.
>

Is it possible though, that your wired connection is managed through
network-manager where the ones that work are static (as in, listed in
/etc/network/interfaces)?

It would seem that network-manager suffers from a common race that
other services do because it stops when dbus stops, and dbus stops on
runlevel [06]. This means on shutdown, stopping it races with umountnfs.

However, its not clear to me if and/or how NetworkManager de-configures
things on SIGTERM, so this may be a moot point.