[Libguestfs] Concurrent scanning of same disk

[Richard W.M. Jones]

On Thu, May 28, 2015 at 10:33:48AM +0300, NoxDaFox wrote:
> To create the snapshots I'm using the libvirt command snapshotCreateXML
> with no flag set. Does libvirt support consistent snapshotting or shall I
> rely on QEMU backup new feature only?

According to: http://wiki.libvirt.org/page/Snapshots
virDomainSnapshotCreateXML is only consistent if the guest is paused
during the operation.

The new qemu feature is called drive-backup
(http://wiki.qemu.org/Features/IncrementalBackup).  Unless things
changed recently, it is not exposed through libvirt, so the only way
to use it is by sending qemu monitor commands
(http://kashyapc.com/2013/03/31/multiple-ways-to-access-qemu-monitor-protocol-qmp/).

This is all pretty bleeding edge.  I still think you'd be better off
just ignoring snapshots that fail and moving on to the next one.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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