Ceph » rbd

Read-only snapshots are now implemented on the kernel client. Still need to have the kvm-rbd implementation.

Then kvm-rbd snapshots implementation also needs to include snapshots rollback.

Yehuda Sadeh wrote:

Then kvm-rbd snapshots implementation also needs to include snapshots rollback.

How would that work? Does qemu provide some sort of rollback interface? I would expect that you just unmount and use rbdtool or something.

The qemu BlockDriver interface includes a bdrv_snapshot_goto callback that is being used to select a snapshot. Snapshots in qemu are expected to be writable so I think the rollback should be applied there.