<html>
<head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
Michal, hi, what's your assumption about instances? Do we want to
shut them down, migrate nova, and restart them or we'd like to
preserve all running VMs?<br>
<br>
-marek<br>
<br>
<div class="moz-cite-prefix">On 04.12.2015 21:50, Michał Jastrzębski
wrote:<br>
</div>
<blockquote
cite="mid:CALc0zUDhq+qzspD1RDGjAQ136kpNzFx2zrfHf8=kf7t9R=xnfw@mail.gmail.com"
type="cite">
<div dir="ltr">
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>
<div>Hey guys,<br>
<br>
</div>
Orchiestrated upgrades is one of our highest
priorities for M in kolla, so following up after
discussion on summit I'd like to suggest an
approach:<br>
<br>
</div>
Instead of creating playbook called "upgrade my
openstack" we will create "upgrade my nova"
instead and approach to each service case by case
(since all of our running services are in dockers,
this is possible).<br>
</div>
<div>We will also make use of image tags as version
carriers, so ansible will deploy new container
only if version tag differs from what we ask it to
deploy. This will help with idempotency of upgrade
process.<br>
</div>
<div><br>
</div>
So let's start with nova. Upgrade-my-nova playbook
will do something like this:<br>
<br>
</div>
0. We create snapshot of our mariadb-data container.
This will affect every service, but it's always good
to have backup and rollback of db will be manual
action<br>
<br>
</div>
<div>1. Nova bootstrap will be called and it will
perform db-migration. Since current approach to nova
code is add-only we shouldn't need to stop services
and old services should keep working on newer
database. Also for minor version upgrades there will
be no action here unless there is migration.<br>
</div>
2. We upgrade all conductor at the same time. This
should take mere seconds since we'll have prebuilt
containers<br>
</div>
3. We will upgrade rest of controller services with using
"series: 1" in ansible to ensure rolling upgrades.<br>
</div>
4. We will upgrade all of nova-compute services on it's own
pace.<br>
<br>
</div>
This workflow should be pretty robust (I think it is) and it
should also provide idempotency.<br>
<br>
</div>
<div>Thoughts?<br>
<br>
</div>
<div>Regards,<br>
</div>
<div>Michal<br>
</div>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">__________________________________________________________________________
OpenStack Development Mailing List (not for usage questions)
Unsubscribe: <a class="moz-txt-link-abbreviated" href="mailto:OpenStack-dev-request@lists.openstack.org?subject:unsubscribe">OpenStack-dev-request@lists.openstack.org?subject:unsubscribe</a>
<a class="moz-txt-link-freetext" href="http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev">http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev</a>
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Marek Zawadzki
Mirantis Kolla Team</pre>
</body>
</html>