live migration fails during upgrades from 7.0 to 8.0

[Timofey Durakov]

Detailed bug description:
live migration fails on pre_live_migration phase because event from neutron is routed to source compute instead of destination one.

The root cause of this problem is that for 7.0 migration object is not used extensivly during live-migration, so migration object has state pre-migrating, while nova api tried to find out destination compute by searching for 'preparing' status.

Steps to reproduce:
run live-migration from 7.0 compute to 8.0 during upgrades procedure.

Expected results:
instance is migrated successfully

Actual result:
migration fails

Reproducibility:
every time.

Workaround:
use cold-migration

Impact:
upgrades.

Description of the environment:
8.0 Controllers.
7.0 Source compute
Neutron required.

[Timofey Durakov (tdurakov)]

this bug is valid only for 8.0, Due to the fact that source compute is not using migration object, I'd prefer not trying to manage migration object on source node(It's almost backporting feature), but order migrations on controller instead.

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: openstack-ci/fuel-8.0/liberty
Change author: Timofey Durakov <email address hidden>
Review: https://review.fuel-infra.org/24690

[Denis Meltsaykin (dmeltsaykin)]

Fix for 8.0 is merged: https://review.fuel-infra.org/#/c/24867/

[Roman Podoliaka (rpodolyaka)]

Merged to 9.1: https://review.fuel-infra.org/#/c/24699/

[Anna Babich (ababich)]

Roman, could you please clarify how it should be verified against env with MOS 9.1?

[Roman Podoliaka (rpodolyaka)]

We do not need to verify it on 9.0 - it's a problem in 8.0 code, we just back ported it through 9.0.

In order to verify this you'll need to deploy a 7.0 env and upgrade it to 8.0.

[Vadim Rovachev (vrovachev)]

status was changed for 8.0 to fix released after disscusion with fuel-qa-upgrade team.

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: mcp/newton
Change author: Timofey Durakov <email address hidden>
Review: https://review.fuel-infra.org/33644

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: 11.0/ocata
Change author: Timofey Durakov <email address hidden>
Review: https://review.fuel-infra.org/34446

[Fuel Devops McRobotson (fuel-devops-robot)]

Fix proposed to branch: mcp/ocata
Change author: Timofey Durakov <email address hidden>
Review: https://review.fuel-infra.org/34827

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Roman Podoliaka <email address hidden> on branch: 11.0/ocata
Review: https://review.fuel-infra.org/34446
Reason: 11.0/ocata is deprecated in favor of mcp/ocata

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Roman Podoliaka <email address hidden> on branch: mcp/ocata
Review: https://review.fuel-infra.org/34827
Reason: already included to https://review.fuel-infra.org/#/c/34846

[Fuel Devops McRobotson (fuel-devops-robot)]

Change abandoned by Roman Podoliaka <email address hidden> on branch: mcp/newton
Review: https://review.fuel-infra.org/33644
Reason: already included to https://review.fuel-infra.org/#/c/33658/