On 01/23/2016 04:02 AM, Dr. David Alan Gilbert wrote: > * Alberto Garcia (be...@igalia.com) wrote: >> On Thu 21 Jan 2016 05:58:42 PM CET, Eric Blake <ebl...@redhat.com> wrote: >>>>>> In general, what do you do to make sure that the data in a new Quorum >>>>>> child is consistent with that of the rest of the array? >>>>> >>>>> Quorum can have more than one child when it starts. But we don't do >>>>> the similar check. So I don't think we should do such check here. >>>> >>>> Yes, but when you start a VM you can verify in advance that all >>>> members of the Quorum have the same data. If you do that on a running >>>> VM how can you know if the new disk is consistent with the others? >>> >>> User error if it is not. Just the same as it is user error if you >>> request a shallow drive-mirror but the destination is not the same >>> contents as the backing file. I don't think qemu has to protect us >>> from user error in this case. >> >> But the backing file is read-only so the user can guarantee that the >> destination has the same data before the shallow mirror. How do you do >> that in this case? > > I think in the colo case they're relying on doing a block migrate > to synchronise the remote disk prior to switching into colo mode.
Yes, we can do a block migration to sync the disk. After the migration finished, we stop block migration before starting colo. Thanks Wen Congyang > > Dave > >> Berto > -- > Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK > > > . >
