[Pacemaker] RFC: How do you upgrade?

[Keisuke MORI]

Hi,

Andrew Beekhof <abeekhof at suse.de> writes:
> Me again,
>
> I'd like to get a sense of how people upgrade their clusters...
>
> * rolling upgrade (node-by-node)
> * big-bang (all nodes at once with all resources stopped)
> * detach and reattach (all nodes at once with resources still running)
> * other?
>
> I'm interested to know how popular the various methods are.

Our preference is:
  detach/reattach  > rolling upgrade  > big-bang
because the shorter service outage the better, of course.

But in the real world, we haven't used the detach/reattach way yet.

In the case of our existing systems that use another commercial
cluster software, it just had no capability to detach/reattach and 
we've used rolling upgrade as long as possible.

In the case of heartbeat/pacemaker, we have used big-bang only because
we have too few experiences about the operation to accomplish
detach/reattach in the production environment.


Besides of this, there is another scenario that our customers
ask us sometime:
 - the application upgrade without stopping the cluster.
i.e. suspend to control a particular resource from heatbeat
(no monitor, no failover action for the resource)
without stopping other resources and the cluster itself.


Thanks,
-- 
Keisuke MORI
NTT DATA Intellilink Corporation