documentation for power recovery

[Kevin Fox]

There is presently no documented procedure for recovering the various clusters in Kolla when a power failure takes out all cluster nodes at once.

This includes a power back on of the following services:
 * Galera/MariaDB
 * RabbitMQ

For Galera, the data should be recovered from the last written server.

For RabbitMQ, if the OpenStack Services just resubmit the messages, they can be freshly initialized, or recovered, whichever is more reasonable.

[Sam Yaple (s8m)]

At the summit RabbitMQ was discussed and to support lights out changes we wil be backporting clusterer

For galera it will need ot be a bit different. The idea is it should be automated, but im not sure the implementation will allow that. I was tasked with figuring that out and ill work on that right now.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/374652
Committed: https://git.openstack.org/cgit/openstack/kolla/commit/?id=d64fc35aeb70b8825754941f7cfd252ef564314a
Submitter: Jenkins
Branch: master

commit d64fc35aeb70b8825754941f7cfd252ef564314a
Author: Paul Bourke <email address hidden>
Date: Thu Sep 22 10:37:34 2016 +0100

    Clean up TODOs from live documentation

    TODOs showing up in ours docs look messy and are of no value to the
    reader.

    Remove these and log bugs for them to be written later.

    Change-Id: Ib9244960e3cedce28b198449898e46668435fce9
    Partial-Bug: #1626455
    Partial-Bug: #1507065
    Partial-Bug: #1626456

[MarginHu (margin2017)]

I met rabbitmq and galera issue when whole cluster was powered off.

I don't know how to recover rabbitmq.

[Jeffrey Zhang (jeffrey4l)]

This is an automated cleanup. This bug report has been closed because it
is older than 18 months and there is no open code change to fix this.
After this time it is unlikely that the circumstances which lead to
the observed issue can be reproduced.

If you can reproduce the bug, please:
* reopen the bug report (set to status "New")
* AND add the detailed steps to reproduce the issue (if applicable)
* AND leave a comment "CONFIRMED FOR: <RELEASE_NAME>"
  Only still supported release names are valid (OCATA, PIKE, QUEENS, ROCKY, ROCKY).
  Valid example: CONFIRMED FOR: OCATA