[libvirt-users] snapshot with libvirt tools or with lvm tools ?

[Lentes, Bernd]

----- On Mar 9, 2018, at 7:05 PM, Bernd Lentes bernd.lentes at helmholtz-muenchen.de wrote:


> 
> It does not work as expected :-(
> My lv's are clustered, but snapshotting a clustered lv requires to activate the
> source lv exclusively on one node, which is not possible when it's mounted and
> files on it are open.
> So i have to try it with libvirt and qemu.
> I'd like to create the snapshot while running the guest, take the backup, and
> merge (or commit) the changes after the copy procedure, still with a running
> guest.
> Is there  a way to do this ? I found
> https://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit , but my
> software seems to be too old:
> I have libvirt-1.2.5-23.3.1. But my virsh offers blockcommit:
> 
> virsh # help blockcommit
>  NAME
>    blockcommit - Start a block commit operation.
> 
>  SYNOPSIS
>    blockcommit <domain> <path> [<bandwidth>] [<base>] [--shallow] [<top>]
>    [--delete] [--wait] [--verbose] [--timeout <number>] [--async]
> 
>  DESCRIPTION
>    Commit changes from a snapshot down to its backing image.
> 
>  OPTIONS
>    [--domain] <string>  domain name, id or uuid
>    [--path] <string>  fully-qualified path of disk
>    [--bandwidth] <string>  bandwidth limit in MiB/s
>    [--base] <string>  path of base file to commit into (default bottom of chain)
>    --shallow        use backing file of top as base
>    [--top] <string>  path of top file to commit from (default top of chain)
>    --delete         delete files that were successfully committed
>    --wait           wait for job to complete
>    --verbose        with --wait, display the progress
>    --timeout <number>  with --wait, abort if copy exceeds timeout (in seconds)
>    --async          with --wait, don't wait for cancel to finish
> 
> But it doesn't work ? Although help offers it ?
> 
> Bernd
> 

Hmm,

it seems i really have a version too old. This is what i get:

virsh # blockcommit windows7x64 /cluster/guests/servers_alive/sa_snap.qcow2 --wait --verbose
error: Operation not supported: committing the active layer not supported yet

Is there no way to achieve what i want ?


Bernd
 

Helmholtz Zentrum Muenchen
Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH)
Ingolstaedter Landstr. 1
85764 Neuherberg
www.helmholtz-muenchen.de
Aufsichtsratsvorsitzende: MinDir'in Baerbel Brumme-Bothe
Geschaeftsfuehrer: Prof. Dr. Guenther Wess, Heinrich Bassler, Dr. Alfons Enhsen
Registergericht: Amtsgericht Muenchen HRB 6466
USt-IdNr: DE 129521671