Comment 3 for bug 1584656

Reviewed: https://review.openstack.org/321599
Committed: https://git.openstack.org/cgit/openstack/fuel-octane/commit/?id=6111d9b9de10b583c5a1699edcd0994e55a739e3
Submitter: Jenkins
Branch: master

commit 6111d9b9de10b583c5a1699edcd0994e55a739e3
Author: Oleg Gelbukh <email address hidden>
Date: Thu May 26 14:54:41 2016 +0000

    Validate nodes roles to exclude upgrade of single controller

    The proper sequence to upgrade controllers is:

    - upgrade primary controller in isolation
    - cut over to the new control plane
    - upgrade remaining controllers at once

    To exclude the possibility to upgrade single controller after
    the cutover, add validation of roles of nodes to upgrade and
    stop if the only node passed to the script is a CIC.

    Change-Id: Ie91ae35acb7e36103004a59c92cb495837e0dca0
    Closes-bug: 1584656