Description of problem: Libvirt currently doesn't handle bitmaps used to drive the incremental backup feature during live migration. Incremental backup would not be possible after a migration without migrating the active bitmaps.
Until this is fixed, RHV need to either: - disable live migration functionality if incremental backup is enabled - delete all checkpoints before live migration, forcing the next backup to be a full backup
Peter, according to what you said on our meetings this issue should be fixed right?
Success code paths of migrations should work at this point. There's a qemu bug which might prevent resuming the source if migration fails in certain phases (unlikely): https://bugzilla.redhat.com/show_bug.cgi?id=1858739 In this bug I want to test it and potentially implement code to transport bitmaps over the migration stream which is supposed to be more efficient.
(In reply to Peter Krempa from comment #3) > Success code paths of migrations should work at this point. There's a qemu > bug which might prevent resuming the source if migration fails in certain > phases (unlikely): https://bugzilla.redhat.com/show_bug.cgi?id=1858739 > > In this bug I want to test it and potentially implement code to transport > bitmaps over the migration stream which is supposed to be more efficient. Peter, can you please clarify what exactly should work? Does a VM that contains checkpoints and bitmaps should migrate successfully? New incremental backup can be taken after the VM was live migrated?
(In reply to Eyal Shenitzky from comment #4) > (In reply to Peter Krempa from comment #3) > > Success code paths of migrations should work at this point. There's a qemu > > bug which might prevent resuming the source if migration fails in certain > > phases (unlikely): https://bugzilla.redhat.com/show_bug.cgi?id=1858739 > > > > In this bug I want to test it and potentially implement code to transport > > bitmaps over the migration stream which is supposed to be more efficient. > > Peter, can you please clarify what exactly should work? > > Does a VM that contains checkpoints and bitmaps should migrate successfully? > New incremental backup can be taken after the VM was live migrated? Yes, both cases should work. Note that the checkpoint definitions are not migrated at this point, so need to be redefined, but since oVirt is already doing that when starting the VM this should not be a problem.
I've filed multiple bugs dealing with specifics sub-issues of this. I'm also re-purposing this bug to specifically track migration of bitmaps when shared storage migration is used. - https://bugzilla.redhat.com/show_bug.cgi?id=1867086 incremental backup: RFE: migrate bitmaps over qemu's migration stream also for shared-storage migration - https://bugzilla.redhat.com/show_bug.cgi?id=1867085 incremental backup: RFE: Migrate bitmaps when migrating VM with --copy-storage-all - https://bugzilla.redhat.com/show_bug.cgi?id=1867084 incremental backup: RFE: Add mechanism to migrate checkpoint definitions with VM Since the bitmaps are for now migrated by qemu and every other problem is tracked. I'll set this bug as test-only.
Per comment6, will remove "NewFeature" tag since it's a TESTONLY issue now. And storage migration part will be tracked in separated RFEs
RHEL AV 8.3.0 has been shipped, therefore marking this BZ CLOSED CURRENTRELEASE.