Cinder/blueprints/multi-attach-volume

[ DRAFT ]

• Launchpad Entry: https://blueprints.launchpad.net/cinder/+spec/multi-attach-volume
• Created: 25th November 2013
• Contributors: Kurt Martin, Zhi Yan Liu, Stephen Gordon

Summary

Currently the Block Storage (Cinder) service only allow a volume to be attached to one instance at a time. The Compute Service (Nova) also makes assumptions in a number of places to this effect as do the APIs, CLIs, and UIs exposed to users. This specification is drafted in support of multi-attach-volume and aims to outline the changes required to allow users to share volumes between multiple guests using either read-write or read-only attachments.

Comments from a previous proposal to this effect (shared-volume) were also taken into consideration. Further background is also available in the etherpad from the relevant session at the Portland (Havana) Design Summit.