iscsi_target table removal breaks rolling upgrade

[Michal Dulko]

Rolling upgrades was broken when iscsi_target table was dropped on https://review.openstack.org/268320

As volume_delete() in db.api was referencing this table in the query, its removal makes it impossible to delete a volume by Liberty cinder-volume.

We cannot stop using a table and drop it in the same release for rolling upgrades to work, we have to stop using it in one release and then drop it in the next or in the post rolling upgrade mechanism (which is still not in place).

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/287800
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=e51edb0dce9d69f1798f226ba1ce927c283688ea
Submitter: Jenkins
Branch: master

commit e51edb0dce9d69f1798f226ba1ce927c283688ea
Author: Gorka Eguileor <email address hidden>
Date: Thu Mar 3 14:37:29 2016 +0100

    Readd iscsi_target table

    Rolling upgrades was broken when iscsi_target table was dropped on
    https://review.openstack.org/268320

    We cannot stop using a table and drop it in the same release for rolling
    upgrades to work, we have to stop using it in one release and then drop
    it in the next or in the post rolling upgrade mechanism (which is still
    not in place).

    So this patch fixes this by removing the dropping and adding another
    migration that ensure that the table is really there. That way we can
    be sure that anyone using M will have the table, which then will get
    dropped in N.

    Closes-Bug: #1553079
    Change-Id: I26586549485a8d745a25161d97d33426fdd52576

[Thierry Carrez (ttx)]

This issue was fixed in the openstack/cinder 8.0.0.0rc1 release candidate.