Detach and attach boot volumes

Registered by Paul Murray

At present boot volumes cannot be detached (or attached) after an instance has been created. This blueprint allows boot volumes to be detached or attached when a VM is shutdown. A VM that has had its boot volume detatched will not be bootable.

Blueprint information

Matt Riedemann
Paul Murray
Zhenyu Zheng
Pending Approval
Series goal:
Slow progress
Milestone target:
Started by
melanie witt

Related branches



Gerrit topic:,topic:bp/detach-boot-volume,n,z

Addressed by: <=== spec MERGED
    Detach and attach boot volumes

Addressed by:
    Adding device_present field to bdm table

Sorry, we have now hit the Non-Priority Feature Freeze for Mitaka. For more details please see: and
--johnthetubaguy 2016.01.30

Addressed by: <=== newton spec
    Detach and attach boot volumes

Addressed by:
    WIP: Attach/detach root volume for shelved_offloaded

Addressed by:
    Enabling detach root volume for shelved_offloaded

There are still pending changes for this and we're now past non-priority blueprint feature freeze for Newton. -- mriedem 20160701

Addressed by:
    Detach and attach boot volumes

We're now past the feature freeze for Ocata, so this will have to be re-proposed for Pike. -- mriedem 20170128

Addressed by:
    Detach and attach boot volumes - Stein

This blueprint is approved for Stein. -- mriedem 20181023

Addressed by:
    WIP: Support attach/detach instance root volume

efried 20190407 setting series goal to train.

Addressed by:
    Add method to allow fetch root_volume BDM by instance_uuid

Addressed by:
    Bump compute service to indicate attach/detach root volume is supported

Addressed by:
    Detach/Attach root volume API changes

We are two days away from Stein feature freeze and this still needs work and integration testing so I am going to defer it from Stein. We will likely need to talk about some of the design implications that came up late in Stein for this during the Train PTG for things like resetting image metadata when attaching a new root volume with a new image, and handling tags/multiattach volumes. -- mriedem 20190305

Gerrit topic:,topic:bp/was,n,z

Addressed by:
    Re-propose detach root volume spec

efried 20190408 fast approved as reproposal for train

efried 20190408 unapproving blueprint pending further spec discussions and updates

I think we're just waiting on a spec amendment for this based on the agreements at the Train PTG:

-- mriedem 20190530

Deferring this out of Train since it wasn't approved and we're about 2 weeks from feature freeze. -- mriedem 20190829


Work Items

Dependency tree

* Blueprints in grey have been implemented.

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