Comment 36 for bug 20960

(In reply to comment #35)
> If I remove the "auto ..." line from /etc/network/interfaces, the problem
> appears again.
>
> I can see the "Configuring network interfaces" and "Waiting for network
> interface to come up" messages, all OK, but the "Synchronizing clock..." failed
> (sometimes).
>

Could you add the following lines to the top (below any comments) of
/etc/init.d/hotplug-net, /etc/hotplug/net.agent and /etc/hotplug/net.ifup

----8<--------8<--------8<--------8<----
exec 2>>/tmp/network.log
date 1>&2
echo "$0" "$@" 1>&2
set -x
---->8-------->8-------->8-------->8----

Then do a reboot, if it fails attach /tmp/network.log

Thanks