Folks,
I have ceph storage for my openstack and configure cinder-volume and cinder-backup service for my disaster solution. I am trying to use the cinder-backup incremental option to save storage space but somehow It doesn't work the way it should work.
Whenever I take incremental backup it shows a similar size of original volume. Technically It should be smaller. Question is does ceph support incremental backup with cinder?
I am running a Yoga release.
$ openstack volume list +--------------------------------------+------------+------------+------+-------------------------------------+ | ID | Name | Status | Size | Attached to | +--------------------------------------+------------+------------+------+-------------------------------------+ | 285a49a6-0e03-49e5-abf1-1c1efbfeb5f2 | spatel-vol | backing-up | 10 | Attached to spatel-foo on /dev/sdc | +--------------------------------------+------------+------------+------+-------------------------------------+
### Create full backup $ openstack volume backup create --name spatel-vol-backup spatel-vol --force +-------+--------------------------------------+ | Field | Value | +-------+--------------------------------------+ | id | 4351d9d3-85fa-4cd5-b21d-619b3385aefc | | name | spatel-vol-backup | +-------+--------------------------------------+
### Create incremental $ openstack volume backup create --name spatel-vol-backup-1 --incremental --force spatel-vol +-------+--------------------------------------+ | Field | Value | +-------+--------------------------------------+ | id | 294b58af-771b-4a9f-bb7b-c37a4f84d678 | | name | spatel-vol-backup-1 | +-------+--------------------------------------+
$ openstack volume backup list +--------------------------------------+---------------------+-------------+-----------+------+ | ID | Name | Description | Status | Size | +--------------------------------------+---------------------+-------------+-----------+------+ | 294b58af-771b-4a9f-bb7b-c37a4f84d678 | spatel-vol-backup-1 | None | available | 10 | | 4351d9d3-85fa-4cd5-b21d-619b3385aefc | spatel-vol-backup | None | available | 10 | +--------------------------------------+---------------------+-------------+-----------+------+
My incremental backup still shows 10G size which should be lower compared to the first backup.