libvirt: Quiescing filesystems with QEMU guest agent during image snapshotting

Registered by Tomoki Sekiyama on 2014-02-07

Currently we need to quiesce filesystems (fsfreeze) manually before snapshotting active instances to create consistent backups. This should be automated for taking daily/weekly backup of instances automatically.

To implement this in KVM instances, nova-compute libvirt driver should request QEMU Guest Agent to freeze the filesystems (and applications if fsfreeze-hook is installed) during the image snapshot.

This feature will be libvirt driver specific, and requires qemu-ga installed in the instances and 'hw_qemu_guest_agent=yes' property in the image metadata. Quiesced volume snapshot is not covered by this blueprint.

Blueprint information

Status:
Complete
Approver:
John Garbutt
Priority:
Low
Drafter:
Tomoki Sekiyama
Direction:
Approved
Assignee:
Tomoki Sekiyama
Definition:
Approved
Series goal:
Accepted for kilo
Implementation:
Implemented
Milestone target:
milestone icon 2015.1.0
Started by
John Garbutt on 2014-06-26
Completed by
John Garbutt on 2015-02-17

Related branches

Sprints

Whiteboard

Gerrit topic: https://review.openstack.org/#q,topic:bp/quiesced-image-snapshots-with-qemu-guest-agent,n,z

Addressed by: https://review.openstack.org/72038
    Libvirt: Fsfreeze during live-snapshot of qemu/kvm instances

Removed from next, as next is now reserved for near misses from the last milestone --johnthetubaguy

Gerrit topic: https://review.openstack.org/#q,topic:bp/quiesced-image-snapshots-with-qemu-guest-agent,n,z

Addressed by: https://review.openstack.org/72038
    Libvirt: Fsfreeze during live-snapshot of qemu/kvm instances

Removed from next, as next is now reserved for near misses from the last milestone --johnthetubaguy

If you are still working on this, please re-submit via nova-specs. If not, please mark as obsolete, and add a quick comment to describe why. --johnthetubaguy (20th April 2014)

Gerrit topic: https://review.openstack.org/#q,topic:bp/proposes,n,z

Addressed by: https://review.openstack.org/99780
    Libvirt: Fsfreeze during live-snapshot of qemu/kvm instances

Not all the reviews have +2s and are not all are close to approval, so moving to juno-3. But please move this back to juno-2, should you get your patches approved in time. --johnthetubaguy 21st July 2014

Sorry, this does not have enough positive reviews to make it for juno-3, please resubmit for kilo. For more information, please contact me (johnthetubaguy) via IRC or email. --johnthetubaguy 2nd September 2014

Addressed by: https://review.openstack.org/126966
    Quiesce filesystems with QEMU guest agent during image snapshot

Addressed by: https://review.openstack.org/138795
    Quiesce boot from volume instances during live snapshot

There is one remaining patch:
https://review.openstack.org/#/c/138795/

Defereing to kilo-2 --johnthetubaguy 18th december 2014

Sorry, we have now hit the non-priority feature freeze for kilo. Please resubmit your spec for the L release. -- ttx on behalf of johnthetubaguy 5th Feb 2015

Blueprint is given an exception for one week --johnthetubaguy 16th Feb 2015

Single require patch merged, so marking complete. --mikalstill 18th Feb 2015

(?)

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