Comment 4 for bug 1619821

Reviewed: https://review.openstack.org/368263
Committed: https://git.openstack.org/cgit/openstack/fuel-octane/commit/?id=44c93bae19d1988ca760aae3f866602e4c0efbe1
Submitter: Jenkins
Branch: stable/mitaka

commit 44c93bae19d1988ca760aae3f866602e4c0efbe1
Author: Ilya Kharin <email address hidden>
Date: Wed Sep 7 16:16:41 2016 +0300

    Use deploy_changes for sets of nodes

    The deploy_changes method involves additional nodes into deployment to
    perform necessary tasks to keep clustered software in a consistent
    state. A direct execution of tasks on a specific set of nodes does not
    involve other necessary nodes and it leads to some failures during
    deployments.

    Change-Id: Ibbdeb40e4287a3170b57c11d88f5aea0afa2b5c7
    Closes-Bug: #1619821