Hi Nova, Happy New Year! I've been working on detach-boot-volume[1] in Stein, we got the initial design merged and while implementing we have meet some new problems and now I'm amending the spec to cover these new problems[2]. The thing I want to discuss for wider opinion is that in the initial design, we planned to support detach root volume for only STOPPED and SHELVED/SHELVE_OFFLOADED instances. But then we found out that we allowed to detach volumes for RESIZED/PAUSED/SOFT_DELETED instances as well. Should we allow detaching root volume for instances in these status too? Cases like RESIZE could be complicated for the revert resize action, and it also seems unnecesary. Thoughts? BR, [1] https://specs.openstack.org/openstack/nova-specs/specs/stein/approved/volume... [2] https://specs.openstack.org/openstack/nova-specs/specs/stein/approved/volume... Kevin Zheng