SUMMARY
File-level restore of Linux VM fails with 'Found Duplicate PV' error
ISSUE
Purpose
Found Duplicate PV error messages with Linux FLR
Description
When attempting to mount iSCSI presented Linux FLR volumes the iSCSI mount script fails with errors similar to the following:
Enter mount point directory: /mnt/backup
Performing iSCSI target discovery from 10.30.12.35.
1: 10.30.12.35:3260,1 iqn.1995-11.com.unitrends.dpu:flr.dc34.ddlinuxtools
Choose a session to restore from: 1
Logging in to iSCSI target iqn.1995-11.com.unitrends.dpu:flr.dc34.ddlinuxtools at 10.30.12.35:3260,1
Scanning iSCSI disk /dev/sdc
Mounting /mnt/backup/disk0/vol0
Found duplicate PV agtF2fFthvRDKoXHHFq060pnL2zo89QX: using /dev/sdc2 not /dev/sda2
Found duplicate PV f5IoeegINIU6WE1O2QJl2Wel3GcE2k6F: using /dev/sdd1 not /dev/sdb1
Found duplicate PV agtF2fFthvRDKoXHHFq060pnL2zo89QX: using /dev/sdc2 not /dev/sda2
Found duplicate PV f5IoeegINIU6WE1O2QJl2Wel3GcE2k6F: using /dev/sdd1 not /dev/sdb1
Failed to get new list of LVM volume groups.
Scanning iSCSI disk /dev/sdd
Found duplicate PV agtF2fFthvRDKoXHHFq060pnL2zo89QX: using /dev/sdc2 not /dev/sda2
Found duplicate PV f5IoeegINIU6WE1O2QJl2Wel3GcE2k6F: using /dev/sdd1 not /dev/sdb1
Found duplicate PV agtF2fFthvRDKoXHHFq060pnL2zo89QX: using /dev/sdc2 not /dev/sda2
Found duplicate PV f5IoeegINIU6WE1O2QJl2Wel3GcE2k6F: using /dev/sdd1 not /dev/sdb1
Failed to get new list of LVM volume groups.
Cause
This issue is commonly seen when multiple linux machines in a VM environment have been cloned. You may alse see this error when connecting to an FLR share from the original machine the backup was made from. If the linux machine being used to mount the recovered FLR image has LVM mount points of it’s own that are similar or direct duplicates with the same UUIDs presented by FLR then the system will be incapable of mounting the LVMs due to either matching mount points and/or matching PV UUIDs.
Resolution
It is not possible to remotely mount LVM volumes on a machine that already has the same LVM UUIDs or PV IDs listed in whole or in part. Instead, select an alternate linux machine or build a new linux machine that does not use LVM mountpoints and use the iSCSI mount script from that machine and recover the files from that alternate machine. In many cases, when LVMs are in use on a Linux machine that is backed up, FLR will not be possible directly to the originating machine.