RBD instance snapshots

Registered by Sébastien Han

Since Havana, Nova supports libvirt_image_type=rbd. This means that you can directly and transparently (for the user) boot VM into Ceph.

However when you perform a snapshot, Nova uses QEMU snapshots, which means that you always get a full block based snapshot. With Ceph backing up all the instances disk, it is really inefficient since the backup file will go locally on the hypervisor and then will be streamed to Glance and finally uploaded into Ceph (assuming Ceph is also backing Glance). From a performance perspective, it will be way easier to use Ceph RBD snapshot directly and much faster.

Blueprint information

Status:
Complete
Approver:
John Garbutt
Priority:
Low
Drafter:
Sébastien Han
Direction:
Approved
Assignee:
Nicolas Simonds
Definition:
Approved
Series goal:
Accepted for mitaka
Implementation:
Implemented
Milestone target:
milestone icon mitaka-3
Started by
John Garbutt
Completed by
John Garbutt

Whiteboard

It is implemented, see https://review.openstack.org/#/c/287954/

Are you going to realize the bp just as what SÉBASTIEN HAN thought in site http://www.sebastien-han.fr/blog/2015/10/05/openstack-nova-snapshots-on-ceph-rbd/ ? --Jackie Qiang(06th Nov 2015)

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:bug/1346525,n,z

Addressed by: https://review.openstack.org/125963
    Implement proper snapshotting for ceph-based ephemeral disks

Gerrit topic: https://review.openstack.org/#q,topic:bp/rbd-instance-snapshots,n,z

Addressed by: https://review.openstack.org/188244
    RBD instance snapshots

Pending Patches
=============

Gerrit topic: https://review.openstack.org/#q,topic:bp/implement-rbd-snapshots-instead-of-qemu-snapshots,n,z

Addressed by: https://review.openstack.org/205282
    libvirt: make snapshot use RBD snapshot/clone when available

Addressed by: https://review.openstack.org/287954
    libvirt: make snapshot use RBD snapshot/clone when available

(?)

Work Items