[ClusterLabs] Resource Agents: pgsql vs. pgsqlms

[Oyvind Albrigtsen]

On 10/07/24 19:18 GMT, Ede Wolf wrote:
>Hello,
>
>we are about to set up a postgresql 15 ha solution and since we already
>have some experience with pacemaker, this seems the obvious route to go
>first.
>
>What however is somewhat confusing are the available resource agents.
>By default the pgsql agent is shipped, at least with debian and
>SLES, that however has a copyright notice dating back to 2012.
>
>Now, when trying to research postgres and pacemaker, most articles do
>talk about PAF, or the pgsqlms resource.
>
>I have so far not been able to find the differences between both, and
>in case PAF is, for one reason or the other, the better or more up
>to date solution, why is it not shipped by default? At least not with
>debian or SLES15?
PAF ended up as a solution due to some changes we couldnt do to the
pgsql agent without the risk of causing issues for existing users
(from what I recall).
>
>Since postgres ha is rather new to us and me having been lucky not
>having had to deal with perl so far, just reading the agents
>themselves does not really shed that much light on this issue.
The pgsql has seen more testing and usage, so I would use that unless
there's a specific reason to use PAF instead.

It's also written in shell, so if you debug by setting trace_ra=1 or
by running "psc resource debug-<action> --full <rsc>" it will also be easier
to debug, as it will list all the commands/checks it's running.

Only negative is that the documentation for promotional pgsql cluster
is dated, so some of the settings for the PostgreSQL config files has
either been renamed or removed, but you'll see all those errors before
creating the resource in the cluster IIRC, so just Google those settings
when you get the errors to find their new equivalent.

https://projects.clusterlabs.org/w/cluster_administration/pgsql_replicated_cluster/


Oyvind Albrigtsen
>
>So in case there is some documentation on comparing these two, or some
>experience, that would be really helpful
>
>Thanks
>
>Ede
>_______________________________________________
>Manage your subscription:
>https://lists.clusterlabs.org/mailman/listinfo/users
>
>ClusterLabs home: https://www.clusterlabs.org/
>