RHEVM - Snapshots
- 3. Snapshots
- 4. Create Snapshot - Initial
- 5. Create Snapshot - Initial
- 6. Create Snapshot - Additional
- 7. Create Snapshot - Additional
- 8. Engine VDSM CreateAllSnapshotsFromVmCommand CreateSnapshotVDSCommand CommandMultiAsyncTasks --> Task to VDSM Run and protect: createVolume creating volume - lvcreate qemu-img create -f qcow2 -F raw -b ... GetImageInfoVDSCommand Create Snapshots - Flow Of Events
- 11. Engine VDSM TryBackToAllSnapshotsOfVmCommand TryBackToSnapshotCommand CreateSnapshotVDSCommand CommandMultiAsyncTasks --> Task to VDSM Run and protect: createVolume creating volume - lvcreate qemu-img create -f qcow2 -F raw -b . GetImageInfoVDSCommand Preview Snapshot - Flow Of Events
- 12. Commit Snapshot
- 13. Commit Snapshot
- 14. Engine VDSM RestoreAllSnapshotsCommand DestroyImageVDSCommand CommandMultiAsyncTasks --> Task to VDSM Run and protect: deleteVolume update volume – lvchange (change tags) delete LV – lvremove GetImageInfoVDSCommand Commit Snapshot - Flow Of Events
- 15. Undo Snapshot
- 16. Undo Snapshot
- 17. Engine VDSM RestoreAllSnapshotsCommand DestroyImageVDSCommand CommandMultiAsyncTasks --> Task to VDSM deleting volume – lvremove update volumes – lvchange GetImageInfoVDSCommand Undo Snapshot - Flow Of Events
- 18. Delete Snapshots The deletion of a snapshot does not necessarily cause the data in the snapshot to be deleted The data from the deleted snapshot and the snapshot created after the deleted snapshot are merged into a single COW volume No data has been removed, only the ability to restore a point in time in the life of the virtual machine hard disk image
- 19. Delete Snapshots
- 20. Delete Snapshots
- 21. Engine VDSM RemoveSnapshotSingleDiskCommand MergeSnapshotsVDSCommand CommandMultiAsyncTasks --> Task to VDSM MergeSnapshots Creating volume - lvcreate (e.g. ..._MERGE) qemu-img convert from to (-O fmt -f fmt ) deleting volume – lvremove GetImageInfoVDSCommand update volumes – lvchange Delete Snapshot - Flow Of Events
Editor's Notes
- #19: When deleting a snapshot, the data from the deleted snapshot and the snapshot created after the deleted snapshot are merged into a single COW volume. After the two snapshots are merged, the resultant volume contains any data that was created or modified prior to the deleted snapshot and after the deleted snapshot. No data has been removed, only the ability to restore a point in time in the life of the virtual machine hard disk image.