api-ref: update migration_policy retype note about encrypted volumes

Nova has historically not supported swap volume operations (via
cinder volume retype / volume migration) for an in-use encrypted
volume.

That was recently addressed via nova bug 1739593.

However, as of change Ibfa64f18bbd2fb70db7791330ed1a64fe61c1355
in nova, depending on the version of libvirt/qemu on the compute host,
a luks-encrypted volume will use native qemu luks decryption. That
does not yet support blockRebase operations which are used during
swap volume due to https://bugzilla.redhat.com/show_bug.cgi?id=760547.

So it's safe to say that for now, a retype which involves a volume
migration is not supported for an in-use encrypted volume.

Change-Id: I7ce992f51d50d00950d3fc4ebb44b69a31a94787
Related-Bug: #1739593
This commit is contained in:
Matt Riedemann 2018-01-25 13:11:37 -05:00
parent aa58746ec2
commit aff9ca2b37
2 changed files with 10 additions and 2 deletions

View File

@ -1008,6 +1008,9 @@ metadata_items:
in: body
required: true
type: integer
# NOTE(mriedem): We can update the migration_policy retype note about encrypted
# in-use volumes not being supported once
# https://bugzilla.redhat.com/show_bug.cgi?id=760547 is fixed.
migration_policy:
description: |
Specify if the volume should be migrated when it is re-typed.
@ -1016,7 +1019,8 @@ migration_policy:
.. note:: If the volume is attached to a server instance and will be
migrated, then by default policy only users with the administrative role
should attempt the retype operation.
should attempt the retype operation. A retype which involves a migration
to a new host for an *in-use* encrypted volume is not supported.
in: body
required: false
type: string

View File

@ -1704,6 +1704,9 @@ metadata_9:
required: false
type: object
min_version: 3.43
# NOTE(mriedem): We can update the migration_policy retype note about encrypted
# in-use volumes not being supported once
# https://bugzilla.redhat.com/show_bug.cgi?id=760547 is fixed.
migration_policy:
description: |
Specify if the volume should be migrated when it is re-typed.
@ -1712,7 +1715,8 @@ migration_policy:
.. note:: If the volume is attached to a server instance and will be
migrated, then by default policy only users with the administrative role
should attempt the retype operation.
should attempt the retype operation. A retype which involves a migration
to a new host for an *in-use* encrypted volume is not supported.
in: body
required: false
type: string