Comment 5 for bug 1572062

Reviewed: https://review.openstack.org/307718
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=59192cfbf9482fe3798cdcd4c2044d8c85f66e95
Submitter: Jenkins
Branch: master

commit 59192cfbf9482fe3798cdcd4c2044d8c85f66e95
Author: Jens Rosenboom <email address hidden>
Date: Tue Apr 19 13:18:52 2016 +0200

    Warn when using null cache backend

    The default backend for oslo_cache is dogpile.cache.null, leading to a
    broken setup when following the current release notes or the deprecation
    message verbatim. So we should at least emit a warning when the config
    does not specify a different backend.

    Note: I'm not sure whether it is possible to amend the release note like
    this or whether there needs a new note to be added, please advise.

    Change-Id: I16647e424d8382dae98f13cb1f73a7e0c0aebaf5
    Closes-Bug: 1572062