Comment 25 for bug 1713786

Reviewed: https://review.openstack.org/503161
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=21150948246d52060a38e93f98982c2e5c9b347d
Submitter: Jenkins
Branch: stable/pike

commit 21150948246d52060a38e93f98982c2e5c9b347d
Author: Matt Riedemann <email address hidden>
Date: Wed Aug 30 15:05:44 2017 -0400

    Create allocations against forced dest host during evacuate

    If a host is specified during an evacuate with the force=True
    flag, conductor bypasses the scheduler. Since the scheduler
    is what creates the "doubled up" allocation on the destination
    node, and the scheduler is bypassed in the force case, we have
    to create the allocations against the destination node in
    conductor directly.

    The unit tests cover the failure scenarios. The functional
    test covers the happy path.

    This is a short-term backportable fix. Long-term we'll likely
    want to call the scheduler even in the 'force' scenario but pass
    a flag to the scheduler to tell it to skip the filters but still
    create the allocation on the destination node so we don't have
    to duplicate that in conductor.

    Change-Id: I6590f0eda4ec4996543ad40d8c2640b83fc3dd9d
    Partial-Bug: #1713786
    (cherry picked from commit d564266a019cb009ece1a63e5d544698f2bf74d1)