reboot hangs

[Jacques Beigbeder]

Hello,

I have an Ubuntu 10.04 10 km away, it is unusable
but I don't known how to reboot, with a SSH connection.
I tried:
	reboot -f
	kill -9 -1
	kill -15 -1

df shows NFS mounts (as administrator I know),
but also a CD and several USB devices.
I tried some 'umount -f' and 'umount -l', they hang.

Is there anything to do to remotely force a reboot?
The box is 10km away, it is a small PC without IPMI.

--
Jacques Beigbeder                    |  Jacques.Beigbeder at ens.fr
Service de Prestations Informatiques |     http://www.spi.ens.fr
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