How do I unlock and/or remove a locked volume?

[Derek Dongray]

I recently decided to move a volume group off of a mixed device (SATA+USB) md raid mirror after encountering the "bio too big" bug (which apparently is likely to cause data corruption, but is classified as WONTFIX! See https://bugzilla.redhat.com/show_bug.cgi?id=498162 or http://lmgtfy.com/?q=bio+too+big+wontfix).

 

The sequence started to use was:

 

1. Fail USB drive and remove from the raid mirror (mdadm).

2. Repartition USB drive (parted).

3. Create Physical Volume on USB drive and add to Volume Group (lvm pvcreate & vgextend).

4. Move Volume Group off of raid mirror (lvm pvmove).

5. Remove raid mirror from Volume Group and stop if being a Physical Volume (lvm vgreduce & pvremove).

6. Stop raid mirror (mdadm).

7. Repartiton SATA drive (parted).

8. Create new SATA-based Physical Volume and add to Volume Group (lvm pvcreate & vgextend).

9. Move volume group off USB-based Physical Volume (pvmove).

It was at this point (after a few hours) that the sysem 'hung' and was totally unresponsive. After powering down and rebooting, I attempted to abort the pvmove (pvmove --abort) but the system locked up again and I rebooted a second time. This time, the abort appeared to succeed, but when I started the pvmove againb I got a message about ignoring the locked volume 'pvmove0'. I proceeded with the remaining step:

 

10. Remove USB-based Physical Volume from the Volume Group and stop it being a Physical Volume (lvm vgreduce & pvremove)

 

The system appears to be running OK, but there is a zero-length, locked Logical Volume which I can't remove.

 

# lvs -a raid/pvmove0

  LV        VG   Attr   LSize Origin Snap%  Move Log Copy%  Convert

  [pvmove0] raid p-C---    0

 

# lvdisplay -a -v raid/pvmove0

    Using logical volume(s) on command line

  --- Logical volume ---

  LV Name                /dev/raid/pvmove0

  VG Name                raid

  LV UUID                2aWJ0g-B5P8-6bAz-zKlk-f4dQ-nwn8-80n12v

  LV Write Access        read/write

  LV Status              NOT available

  LV Size                0

  Current LE             0

  Segments               0

  Allocation             contiguous

  Read ahead sectors     auto

 

# tail -n11 /etc/lvm/backup/raid

                pvmove0 {

                        id = "2aWJ0g-B5P8-6bAz-zKlk-f4dQ-nwn8-80n12v"

                        status = ["READ", "WRITE", "PVMOVE", "LOCKED"]

                        flags = []

                        allocation_policy = "contiguous"

                        segment_count = 0

                }

        }

}

 

The volume is locked (as shown from the backup information output) so "lvremove --force raid/pvmove0"  simply complains "Can't remove locked LV pvmove0", but "pvmove --abort" (which would normally unlock this) does nothing because no pvmove is in progress.

 

So the question (as in the subject) is how do I unlock and/or remove a locked volume?

 

Thanks.

--

Derek.

 

[Derek Dongray]

OK. I decided this is probably impossible (or at least very difficult) since no-one replied or even commented after over 12 hours, so I too the alternative roure of creating a new Volume Group, copying and deleting (if possible) all the Logical Volumes in the 'corrupt' VG, rebooting using the new VG, then deleting the old VG and moving everything to the right Physical Volumes.

 

Of course, I'd still like to know if a damaged pvmove0 (pvmove, locked) volume can be unlocked and deleted when 'pvmove --abort' does not do the job.

--
Derek.

[Gilles Mocellin]

Le Saturday 25 June 2011 00:56:29 Derek Dongray, vous avez écrit :
[...]

> Of course, I'd still like to know if a damaged pvmove0 (pvmove, locked)
> volume can be unlocked and deleted when 'pvmove --abort' does not do the
> job.

You can try "dmsetup remove". It also has a force option.

[...]