openstack team mailing list archive

[Florian Haas <florian@xxxxxxxxxxx>]

On Tue, Feb 21, 2012 at 12:34 PM, i3D.net - Tristan van Bokkem
<tristanvanbokkem@xxxxxx> wrote:
> Ho Florian,
>
> I respect your opinion of course and I am not here to start a fight. Point
> is, how I understand it Nova really isn't very flexible on High Availability
> terms. I have now a master/master mysql setup with a Virtual IP working just
> to work around the shortcomings Nova imo introduces. This same story goes
> for RabbitMQ, I need to setup RabbitMQ in HA (which is fine) but I need to
> setup a Virtual IP for it as well just so Nova can correctly connect to it.
> Without the VIP the hole point of setting it up in a cluster is useless as
> you still will point nova to one single host.

Well yes, that's a given. Thankfully you have a set of tools at hand
that make this very easy.

> It shouldn't be that hard to make Nova listen to multiple mysql addresses
> and rabbitmq hosts in a cluster?

And then what? So it talks to multiple MySQLs, and you'll have to take
care of database consistency by yourself. Or it talks to multiple
RabbitMQs, and you'll need a way to synchronize your queues.

Question is, as Darren has also said in this thread, whether you
really want HA, or scaleout. Or both. But interestingly, Pacemaker can
serve you just fine for all of that.

Let me repeat, though, I am clearly biased -- see URL in my sig block
for details.

Cheers,
Florian

-- 
Need help with High Availability?
http://www.hastexo.com