failed to gnt-backup export

What software version are you running? Please provide the output of "gnt-
cluster --version", "gnt-cluster version", and "hspace --version".

gnt-cluster (ganeti v2.4.5) 2.4.5

Software version: 2.4.5
Internode protocol: 2040000
Configuration format: 2040000
OS api version: 20
Export interface: 0

What distribution are you using?

Debian 6.0.10 Squeeze

What steps will reproduce the problem?
1. create an instance with debootstrap (Debian 6.0 for example)
2. add extra disk (LVM)
3. run gnt-backup export

What is the expected output? What do you see instead?
Expected: backup of both disks
Instead: backup of 1 disk (/dev/vda1 -> snapshot/0) is OK  but it failed for 
LVM (snapshot/1)

Please provide any additional information below.
Here is the link to the original post: 
https://groups.google.com/forum/#!topic/ganeti/jiSKPe1UsoA

I will have to do some modifications on a instance. Before doing anything, I 
would like to have a backup (just in case something goes wrong).
Unfortunately I can't create a backup.

Here is the command:

    gnt-backup export -n cluster1-node1.local test3.local

    Thu Mar 26 11:03:08 2015 Shutting down instance test3.local
    Thu Mar 26 11:03:24 2015 Creating a snapshot of disk/0 on node cluster1-node4.local
    Thu Mar 26 11:03:25 2015 Creating a snapshot of disk/1 on node cluster1-node4.local
    Thu Mar 26 11:03:25 2015 Starting instance test3.local
    Thu Mar 26 11:03:26 2015 Exporting snapshot/0 from cluster1-node4.local to cluster1-node1.local
    Thu Mar 26 11:03:26 2015 Exporting snapshot/1 from cluster1-node4.local to cluster1-node1.local
    Thu Mar 26 11:03:29 2015 snapshot/0 is now listening, starting export
    Thu Mar 26 11:03:29 2015 snapshot/1 is now listening, starting export
    Thu Mar 26 11:03:31 2015 snapshot/0 is receiving data on cluster1-node1.local
    Thu Mar 26 11:03:31 2015 snapshot/1 is receiving data on cluster1-node1.local
    Thu Mar 26 11:03:31 2015 snapshot/0 is sending data on cluster1-node4.local
    Thu Mar 26 11:03:34 2015 snapshot/1 finished receiving data
    Thu Mar 26 11:03:34 2015  - WARNING: export 'export-2015-03-26_11_03_31-uMzX3j' on cluster1-node4.local failed: Exited with status 1
    Thu Mar 26 11:03:34 2015 snapshot/1 failed to send data: Exited with status 1 (recent output: Cannot interpret kpartx output and get partition mapping)
    Thu Mar 26 11:03:34 2015 Removing snapshot of disk/1 on node cluster1-node4.local
    Thu Mar 26 11:03:41 2015 snapshot/0 sent 0M, 0.0 MiB/s
    Thu Mar 26 11:04:43 2015 snapshot/0 sent 404M, 7.3 MiB/s
    Thu Mar 26 11:05:45 2015 snapshot/0 sent 1.2G, 13.5 MiB/s
    Thu Mar 26 11:06:46 2015 snapshot/0 sent 1.9G, 12.0 MiB/s
    Thu Mar 26 11:07:48 2015 snapshot/0 sent 2.8G, 14.2 MiB/s
    Thu Mar 26 11:08:45 2015 snapshot/0 finished receiving data
    Thu Mar 26 11:08:45 2015 snapshot/0 finished sending data
    Thu Mar 26 11:08:45 2015 Removing snapshot of disk/0 on node cluster1-node4.local
    Thu Mar 26 11:08:46 2015 Finalizing export on cluster1-node1.local
    Failure: command execution error:
    Export failed, errors in disk export: disk(s) 1

The result of the command "fdisk -l" on my instance test3.local (Debian 6):

    Disk /dev/vda: 10.7 GB, 10737418240 bytes
       Device Boot      Start         End      Blocks   Id  System
    /dev/vda1   *           1        1305    10482412   83  Linux
    ..
    Disk /dev/vdb: 322.1 GB, 322122547200 bytes
    Disk /dev/vdb doesn't contain a valid partition table
    ...
    Disk /dev/dm-0: 322.1 GB, 322118352896 bytes
    Disk /dev/dm-0 doesn't contain a valid partition table

We are using LVM and DRBD. The primary node of test3.local is 
cluster1-node4.local, and the secondary node is cluster1-node3.local

Result for "gnt-instance list":

    test3.local            kvm        debootstrap+default cluster1-node4.local running     10.0G
Original issue reported on code.google.com by dalfga...@gmail.com on 27 Mar 2015 at 2:47
olopez32 / ganeti

failed to gnt-backup export #1055
