WARNING: Duplicate VG name XXX: Existing XXX (created here) takes precedence over XXX

  On one fine day , some issue got reported to you like "Duplicate VG name". You will think like, from where on earth you got this error. You thought,  You have not added any  VG with same name, moreover if you try so the LVM will not allow. Then how come there is a error called Duplicate VG. Well you have to go to flashback. Is there any DISK or LUN has been added to the server recently ? If yes, it would have been the cause of the problem. The LUN/DISK  that have been added to the system recently has a duplicate LUN or having the LVM metadata on it, which is having the same VG name that is in our system. So in between if your server got rebooted, you'll get a similar kind of message as given below. We got the cause of the issue, now lets check out the solution.

  WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o  WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o  WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o  WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

 Solution: 1. Run a vgdisplay command.

 Server1:/dev # vgdisplay   WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o   WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o   WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  --- Volume group ---

  VG Name               test

  System ID

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  3

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                2

  Open LV               0

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               45.00 GiB

  PE Size               4.00 MiB

  Total PE              11519

  Alloc PE / Size       10496 / 41.00 GiB

  Free  PE / Size       1023 / 4.00 GiB

  VG UUID               f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  --- Volume group ---

  VG Name               test

  System ID

  Format                lvm2

  Metadata Areas        1

  Metadata Sequence No  3

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                2

  Open LV               0

  Max PV                0

  Cur PV                1

  Act PV                1

  VG Size               45.00 GiB

  PE Size               4.00 MiB

  Total PE              11519

  Alloc PE / Size       10496 / 41.00 GiB

  Free  PE / Size       1023 / 4.00 GiB

  VG UUID               h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd

  WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd (created here) takes precedence over f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

 

 2. Now you'll find 2 VG's with same name, but with a different VG UUID.

 3. Now unmount the related file system and deactivate the LV's.

 umount /mountpoint 

 vgchange -an test 

4. Though it'll not be required, but if required , You need to scan all disks for volume groups and rebuild caches: 

# vgscan --mknodes 

5. Now rename the VG.

Server1:/ # vgrename f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o unkntestvg

  WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd takes precedence over exported f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o<

  WARNING: Duplicate VG name test: Existing h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd takes precedence over exported f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  WARNING: Duplicate VG name test: h02jwQ-g8xO-Ne4p-QUi4-8sfN-gnje-apKxSd takes precedence over exported f3STwh-t7CJ-4fh0-HNhE-xmPr-pzWg-Tqm05o

  Volume group "test" successfully renamed to "unkntestvg"

6. Now check the devices that is attached to the renamed VG.

Server1:/ # lvs -o +devices 

 LV             VG       Attr      LSize   Pool Origin Data%  Move Log Copy%  Convert Devices

   lv_oracle      unkntestvg -wi------  40.00g                                            /dev/sdau1(0)

  lv_usrsap      unkntestvg -wi------   1.00g                                            /dev/sdau1(10240)

 7.  Now activate LV's in both the VG's.

Server1:/ # vgchange -ay unkntestvg   2 logical volume(s) in volume group "unkntestvg" now active Server1:/ #vgchange -ay test 2 logical volume(s) in volume group "test" now active

8. Now mount LV in both the VG. Check your data and take necessary steps.

  /dev/mapper/test-lv_oracle                                      40G   15G   23G  40% /oracle

/dev/mapper/test-lv_usrsap                                    1008M  121M  836M  13% /usr/sap /dev/mapper/unkntestvg-lv_oracle                                40G  4.0G   34G  11% /mnt /dev/mapper/unkntestvg-lv_usrsap                              1008M   34M  924M   4% /mnt/usrsap