[linux-lvm] UUID

[Matt Schillinger]

Can someone explain the UUID, etc  on a volume and on VGs?

Is the UUID stored on the volume, or on the host machine?

The reason I ask, is that I have a parrallel scsi raid, which is
connected to 2 machines.  If i reboot both machines, or go through a
vgexport/import procedure (while online), i can see the VGs and LVs on
both machines.. can even mount the volumes simultaneously (It was only a
test.. I understand that it is not a Shared Filesystem, and would never
do simultaneous mounts on production filesystems). 

This is what I believe to be the case:

1. The UUID is stored on the volume itself, and the VG data is stored
somewhere on the disks also.
2. The import/export/activated/deactivated status of a volume is held on
the host machine.

this allows 2 machines to see the same VG/LVs. 

Is this correct?  And is it supported as a function of LVM, or am I in
'unsupported' territory?


-- 
Matt Schillinger
mschilli at vss.fsi.com