What does "Found duplicate PV bUO24Zb2mJGJrTSTRs87Lwrumlu72A1T: using /dev/loop2 not /dev/loop1" mean?

The "Found duplicate PV" message indicates that two volumes (in this case /dev/loop1 and /dev/loop2) contain the same Universally Unique Identification (UUID) label in their LVM metadata. In other words, the volumes /dev/loop1 and /dev/loop2 are identical as far as LVM is concerned. There are several reasons why you would receive this type of messages:

dd if=/dev/zeroof=/tmp/test.img bs=1M count=10
losetup /dev/loop1 /tmp/test.img
pvcreate /dev/loop1
vgcreate test /dev/loop1
lvcreate -l2 -n oops test

Then either something like the commands below, or you've created a snapshot or clone of the volume from the SAN then presented the new snapshot or clone back to this system.

cp /tmp/test.img /tmp/test2.img
losetup /dev/loop2 /tmp/test2.img
pvscan

None: FrequentlyAskedQuestions/FoundDuplicatePV (last edited 2008-12-09 23:12:56 by DavidRobinson)