[ClusterLabs] MySQL cluster with auto failover

[Ken Gaillot]

On Tue, 2023-09-12 at 10:28 +0200, Damiano Giuliani wrote:
> thanks Ken,
> 
> could you point me in th right direction for a guide or some already
> working configuration?
> 
> Thanks
> 
> Damiano

Nothing specific to galera, just the usual Pacemaker Explained
documentation about clones.

There are some regression tests in the code base that include galera
resources. Some use clones and others bundles (containerized). For
example:

https://github.com/ClusterLabs/pacemaker/blob/main/cts/scheduler/xml/unrunnable-2.xml


> 
> Il giorno lun 11 set 2023 alle ore 16:26 Ken Gaillot <
> kgaillot at redhat.com> ha scritto:
> > On Thu, 2023-09-07 at 10:27 +0100, Antony Stone wrote:
> > > On Wednesday 06 September 2023 at 17:01:24, Damiano Giuliani
> > wrote:
> > > 
> > > > Everything is clear now.
> > > > So the point is to use pacemaker and create the floating vip
> > and
> > > > bind it to
> > > > sqlproxy to health check and route the traffic to the available
> > and
> > > > healthy
> > > > galera nodes.
> > > 
> > > Good summary.
> > > 
> > > > It could be useful let pacemaker manage also galera services?
> > > 
> > > No; MySQL / Galera needs to be running on all nodes all the
> > > time.  Pacemaker 
> > > is for managing resources which move between nodes.
> > 
> > It's still helpful to configure galera as a clone in the cluster.
> > That
> > way, Pacemaker can monitor it and restart it on errors, it will
> > respect
> > things like maintenance mode and standby, and it can be used in
> > ordering constraints with other resources, as well as advanced
> > features
> > such as node utilization.
> > 
> > > 
> > > If you want something that ensures processes are running on
> > > machines, 
> > > irrespective of where the floating IP is, look at monit - it's
> > very
> > > simple, 
> > > easy to configure and knows how to manage resources which should
> > run
> > > all the 
> > > time.
> > > 
> > > > Do you have any guide that pack this everything together?
> > > 
> > > No; I've largely made this stuff up myself as I've needed it.
> > > 
> > > 
> > > Antony.
-- 
Ken Gaillot <kgaillot at redhat.com>