[Users] unable to detect lvm volume group

[Benjamin Henrion]

Hi,

I am trying to dump some containers with vzdump, I created a 20G file
mounted in loopback in /var/lib/vz:

# mount
/dev/dm-0 on /var/lib/vz type ext3 (rw)
# df -lha /dev/dm-0
Filesystem            Size  Used Avail Use% Mounted on
/dev/dm-0              20G  1.3G   17G   8% /var/lib/vz

I have a container named 101 running, I try to run the vzdump with
--snapshot, and it gives:

===================================================================
# env LANG=C vzdump --snapshot --dumpdir=/root/openvz/dump/ 101
INFO: starting new backup job: vzdump --snapshot
--dumpdir=/root/openvz/dump/ 101
INFO: Starting Backup of VM 101 (openvz)
INFO: CTID 101 exist mounted running
INFO: status = CTID 101 exist mounted running
INFO: mode failure - unable to detect lvm volume group
INFO: trying 'suspend' mode instead
INFO: backup mode: suspend
INFO: bandwidth limit: 10240 KB/s
INFO: starting first sync /var/lib/vz/private/101/ to
/root/openvz/dump/vzdump-openvz-101-2010_07_07-17_47_28.tmp
===================================================================

Any idea how to fix the "unable to detect lvm volume group" problem?

Lvdisplay and vgdisplay gives:

===================================================================
# lvdisplay
  --- Logical volume ---
  LV Name                /dev/openvzgroup2/openvzvol2
  VG Name                openvzgroup2
  LV UUID                0yBA8w-dZoS-236K-XlGR-BLqk-8IQa-GZmNQU
  LV Write Access        read/write
  LV Status              available
  # open                 1
  LV Size                19.53 GiB
  Current LE             5000
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           254:0

# vgdisplay
  --- Volume group ---
  VG Name               openvzgroup2
  System ID
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  2
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               20.00 GiB
  PE Size               4.00 MiB
  Total PE              5119
  Alloc PE / Size       5000 / 19.53 GiB
  Free  PE / Size       119 / 476.00 MiB
  VG UUID               WyXBzc-AZOR-V2o9-JMWk-mOzv-jzRL-ZlqQai
===================================================================

--
Benjamin Henrion <bhenrion at ffii.org>
FFII Brussels - +32-484-566109 - +32-2-4148403
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