[libvirt-users] qemu-img snapshots with backing stores?

[Sean Abbott]

So, I was attempting to use qemu snapshots with backing stores.  The
QEMU docs (http://wiki.qemu.org/Documentation/CreateSnapshot) make it
sound like you simply point your qemu at the snapshot after it's
creation, and you're golden.

When attempting this with libvirt, though, it fails.

I created a snapshot using the above tutorial.  the resulting file is
disk.0, and a qmeu-img info on it returns:

image: disk.0
file format: qcow2
virtual size: 29G (31457280000 bytes)
disk size: 140K
cluster_size: 65536
backing file: /var/lib/one/public/lin_client_current.qcow2 (actual path:
/var/lib/one/public/lin_client_current.qcow2)

So that all looks groovy, right?

Then, I created (via opennebula) an xml deployment file like so: 
http://paste.ubuntu.com/1027145/

When I attempt to do a virsh create, I get the following errors:

virsh # create deployment.0
error: Failed to create domain from deployment.0
error: internal error process exited while connecting to monitor:
file=/var/lib/one/vm/56/images/disk.0,if=none,id=drive-virtio-disk0,boot=on,format=qcow2,cache=none
qemu-kvm: boot=on|off is deprecated and will be ignored. Future versions
will reject this parameter. Please update your scripts.
qemu-system-x86_64: -drive
file=/var/lib/one/vm/56/images/disk.0,if=none,id=drive-virtio-disk0,boot=on,format=qcow2,cache=none,boot=on:
could not open disk image /var/lib/one/vm/56/images/disk.0: Invalid argument

So...something isn't working. Is it possible to do this, or should I
give up on this path?

Thanks!

sean