Support for Multiple driver backends in a single manager

Registered by Nirmal Ranganathan on 2012-08-08

Allow managing multi volume backends from a single volume manager. Right now there's a 1-1 mapping of manager-driver. This blueprint aims to provide suport for 1-n manager-drivers, where by certain volume drivers that really don't depend on local host storage can take advantage of this to manager multi backends without having to run multi volume managers.

The thought is to use the existing configuration sections to distinguish the various drivers to load for a single volume manager.

Current limitation of the multi backend is that there is 1 backend to volume_type. A volume_type must be set up and that must also correspond to the flag set in each [backend]. See example below.

Blueprint information

Status:
Complete
Approver:
John Griffith
Priority:
Medium
Drafter:
Nirmal Ranganathan
Direction:
Approved
Assignee:
Michael Basnight
Definition:
Approved
Series goal:
Accepted for grizzly
Implementation:
Implemented
Milestone target:
milestone icon 2013.1
Started by
Thierry Carrez on 2012-11-13
Completed by
Thierry Carrez on 2013-02-19

Related branches

Sprints

Whiteboard

As per the http://eavesdrop.openstack.org/meetings/cinder/2013/cinder.2013-01-16-16.02.log.html meeting, we will be doing the following.

Some new issues have come to light, as per the big lebowski. See the wiki article for the different perspectives on the blueprint.

http://wiki.openstack.org/cinder-multi-backend

Going with option 1.

* Nice to have(s)
hub_cap: One other thing to think about is if we can enforce not allowing this in the case of LVM

Gerrit topic: https://review.openstack.org/#q,topic:bp/multi-volume-backends,n,z

Addressed by: https://review.openstack.org/21815
    Update cinder-volume to enable multi volume support

#### OLD CODE AND OLD INFO #####
Addressed by: https://review.openstack.org/11192
    Adding support for multiple volume backends in a single volume-manager.

Addressed by: https://review.openstack.org/20347
    Update cinder-volume to enable multi volume support

(?)

Work Items

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