[libvirt-users] virsh create snapshot not honoring diskspec?

[Silver Sky Soft Services, Inc.]

On Thu, Aug 13, 2015 at 1:16 PM, Eric Blake <eblake at redhat.com> wrote:
>
> On 08/07/2015 09:53 AM, Silver Sky Soft Services, Inc. wrote:
> > Hi,
> > I'm trying to create a snapshot on a specific disk by using diskspec
> > option. However, libvirt/virsh seems to ignore it and takes a snapshot of
> > all disks. Am I using this option incorrectly?
> >
> > In below examples, I'm trying to snapshot only vdb. However even vda is
> > getting snapshotted regardless of diskspec. Is this a known issue?
> >
> > I'm on CentOS 7.1, libvirtd (libvirt) 1.2.8, virsh 1.2.8
> >
> > [root at localhost scripts]# virsh domblklist centos_nfs
> > Target     Source
> > ------------------------------------------------
> > vda        /var/lib/libvirt/images/centos_nfs.SNAP_2015-08-07-081800
> > vdb        /var/lib/libvirt/images/centos_nfs_storage.SNAP_2015-08-07-081800
> > hdc        -
> >
> > [root at localhost scripts]# virsh snapshot-create-as --domain centos_nfs
> > --name SNAP_2015-08-07-090909 --no-metadata --disk-only --atomic --diskspec
> > vdb,snapshot=external
>
> This command line did not give a diskspec for vda, so the action for vda
> defaults to whatever the <domain> XML says is default for that disk .
>
> Try giving:
>  --diskspec vdb,snapshot=external --diskspec vda,snapshot=none
> to explicitly override the <domain> defaults for both disks at once.
>

Thanks Eric. That helped. Although minor note was the option was
"snapshot=no" instead of "snapshot=none". Just to put in these
archives, the working command:
virsh snapshot-create-as --domain cento_os --name snap3 --no-metadata
--disk-only --atomic --diskspec vdb,snapshot=no --diskspec
vda,snapshot=external

-KiranK