redundant paths to the same device.
This class reacts to a label in the first sector of the device,
which is created the following way:
# "0123456789abcdef012345..."
# "<----magic-----><-id-...>
echo "GEOM::FOX someid" | dd of=/dev/da0 conv=sync
NB: Since the fact that multiple disk devices are in fact the same
device is not known to GEOM, the geom taste/spoil process cannot
fully catch all corner cases and this module can therefore be
confused if you do the right wrong things.
NB: The disk level drivers need to do the right thing for this to
be useful, and that is not by definition currently the case.
