If I want to go back to a snapshot, what is the difference between snapshot-current and snapshot-revert? What happens to disk sectors of the current state when reverting to another snapshot? I'm using qemu qcow2.
Kashyap Chamarthy
2014-May-08 12:16 UTC
Re: [libvirt-users] snapshot-current vs snapshot-revert
On Wed, May 07, 2014 at 11:42:36AM +0100, bitozoid wrote:> If I want to go back to a snapshot, what is the difference between > snapshot-current and snapshot-revert?'snapshot-current' will show you the current snapshot name: $ virsh snapshot-current ostack-controller --name snap1 Or the XML dump of the current snapshot if you invoke it without any parameters: $ virsh snapshot-current ostack-controller <domainsnapshot> <name>snap1</name> <state>running</state> . . .> What happens to disk sectors of the current state when reverting to > another snapshot? I'm using qemu qcow2.I'd say they'd be lost/erased (Eblake/others would correct me if I'm wrong). When you do a revert, you'd be at the same state when you created the snapshot. Also, you haven't mentioned if you're using internal snapshots, or external. Assuming you're using QEMU internal snapshots (original and the delta are in the same qcow2 file), the virsh man page (section 'snapshot-revert') gives you some details including risk scenarios. -- /kashyap