[Pacemaker] Providing high availability for multiple applications.

[Ron Kerry]

On 10/22/12 3:34 AM, Guillaume Belrose wrote:
> Hi all,
>
> I've been investigating Pacemaker/Corosync for providing high availability for a wide range of
> applications. I found this combination to be very useful. Some of my applications require a
> fail-over cluster while others require load-balanced cluster.
>
> I am wondering what are the best practices when managing the clusters for those applications.
>
> Currently, each application runs in a separate/dedicated cluster. I essentially have different
> corosync configurations, one per cluster.
>
> I am wondering if it is not better to setup 1 large Pacemaker cluster which is partitioned in such a
> way that certain resources are dedicated to a certain application (using node attribute expressions
> like in
> http://www.clusterlabs.org/doc/en-US/Pacemaker/1.0/html/Pacemaker_Explained/ch-rules.html#s-expression-attribute).
>
> There would only be 1 Corosync configuration, and the cluster is partitioned using some naming
> convention. It seems to me that this would simplify management.
>
> I wonder what people think about this approach.
>
> Many thanks in advance.
>
> Guillaume.
>
>
>

Complexity is the enemy of reliability. Putting all your eggs in a single corosync cluster basket 
would lead to lower reliability. These things are always a balancing act between cost (in terms of 
hardware resources and sysadmin resources) and reliability. I

-- 

Ron Kerry         rkerry at sgi.com
Global Product Support - SGI Federal