[ClusterLabs] General Capabilities Question

[Ken Gaillot]

On Thu, 2018-04-12 at 21:09 -0700, Cliff Burdick wrote:
> Hi, I had a general question about Pacemaker to see if it would work
> for a somewhat unique situation. I have a cluster of 10 active
> machines + 2 standby that each have 3 interfaces (2 control, 1
> management). I want each of the control interfaces to use virtual
> IPs, such that if any of those 10 nodes fail, one of the two standby
> nodes can assume the virtual IPs of the failed node. For the virtual
> IPs, I wanted the failover to happen entirely in userspace and
> essentially just receive a notification that a node failed, and allow
> my application on the standby node to do all of the virtual IP
> reconfiguration. By userspace I mean that these interfaces are
> typically not configured by Linux, so the failure of those interfaces
> and the configuration would be done by a user script.
> 
> The reason I'm looking at pacemaker is it appears to be robust on
> node failure detections, and the STONITH is something I'd like to do.
> Is this something pacemaker could be configured to do, and if so,
> which part of the documentation should I focus on?

Yes, that's what Pacemaker is designed for. I recommend starting with
the "Clusters from Scratch" document to get familiar with the basics.
Then you can look at "Pacemaker Explained" to get detailed info about
particular configuration options (especially constraints).

I'm not sure what your interface/VIP stuff does, but you probably want
to write your own OCF resource agent (see IPaddr2 as an example) to
manage the IP, and let Pacemaker call it as needed.
-- 
Ken Gaillot <kgaillot at redhat.com>