Set migration status to 'error' on live-migration failure

[OpenStack Infra]

https://review.openstack.org/215483
Dear bug triager. This bug was created since a commit was marked with DOCIMPACT.
Your project "openstack/nova" is set up so that we directly report the documentation bugs against it. If this needs changing, the docimpact-group option needs to be added for the project. You can ask the OpenStack infra team (#openstack-infra on freenode) for help if you need to.

commit d61e15818c1d108275b3286a6665fa3e6540e7e7
Author: Rajesh Tailor <email address hidden>
Date: Thu Jul 2 03:22:01 2015 -0700

    Set migration status to 'error' on live-migration failure

    (A) In resize, confirm-resize and revert-resize operation, migration status
    is marked as 'error' in case of failure for respective operation.

    Migration object support is added in live-migration operation, which mark
    migration status to 'failed' if live-migration operation fails in-between.

    To make live-migration consistent with resize, confirm-resize and revert-
    resize operation, it needs to mark migration status to 'error' instead of
    'failed' in case of failure.

    (B) Apart from consistency, proposed change fixes issue (similar to [1])
    which might occur on live-migration failure as follows:
    If live-migration fails (which sets migration status to 'failed') after
    copying instance files from source to dest node and then user request for
    instance deletion. In that case, delete api will only remove instance
    files from instance.host and not from other host (which could be either
    source or dest node but not instance.host). Since instance is already
    deleted, instance files will remain on other host (not instance.host).

    Set migration status to 'error' on live-migration failure, so that
    periodic task _cleanup_incomplete_migrations [2] will remove orphaned
    instance files from compute nodes after instance deletion in above case.

    [1] https://bugs.launchpad.net/nova/+bug/1392527
    [2] https://review.openstack.org/#/c/219299/

    DocImpact: On live-migration failure, set migration status to 'error'
    instead of 'failed'.

    Change-Id: I7a0c5a32349b0d3604802d22e83a3c2dab4b1370
    Closes-Bug: 1470420

[Matt Riedemann (mriedem)]

I don't know what documentation impact this has, beyond possibly a release note in nova in the 'other' section.

[Matt Riedemann (mriedem)]

For the release note, I'd put this in the 'other' or 'fixes' section.

[Matt Riedemann (mriedem)]

Note that we don't want to put the migration.status in the os-migrations api-ref docs because we want to avoid codifying the migration status in the API until we have an actual state machine for migrations. The migration.status today is really just meant to be informative and client applications shouldn't base logic off of the value.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/362448

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/newton
Review: https://review.openstack.org/372519

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/362448
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=a7c0a84a1e50a9f83acd27ece64f393ac454cf7f
Submitter: Jenkins
Branch: master

commit a7c0a84a1e50a9f83acd27ece64f393ac454cf7f
Author: Anusha Unnam <email address hidden>
Date: Mon Aug 29 21:09:48 2016 +0000

    Add a new release note

    Add a new reno note to specify that migration status is changed
    from 'failed' to 'error' on live-migration failure. That was landed
    as change I7a0c5a32349b0d3604802d22e83a3c2dab4b1370

    Change-Id: I4e1693fa52bcb33b8770ec59640890abd2b911c8
    Closes-bug: #1588888

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 14.0.0.0rc2 release candidate.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 15.0.0.0b1 development milestone.