Can logical replication be a solution to my current MariaDB/Galera setup?

Michael Grimm <trashcan@ellael.org>

From: Michael Grimm <trashcan@ellael.org>
To: pgsql-general@lists.postgresql.org
Date: 2026-05-22T13:18:35Z
Lists: pgsql-general
Hi,

this is my first post to this mailing list, and I hope that I chose the correct mailing list.

I have never run a postgres server before, but I do run a mariadb galera cluster [1] for storing emails by an IMAP server [2]. Distribution and failover is dealt by haproxy [3]. This mail server setup has to deal with less than 250 mails a day, a database size of under 6 GB, and a handful of users. You see, that this system is bored to death ;-)  

I have read a lot about replication in order to find something comparable to a galera cluster with its multi master capabilities. Now, I have learned that multi master can only be achieved by using third party plugins. Not all of those are available for my FreeBSD systems, though.

As a newbie I do currently tend to use logical replication with mutual publish and subscribe instead, either by pglogical2 or "self-made". I am in the -probably naive- impression that this could work. As before, failover will be handled by haproxy by simply directing read/write access to another postgres node available. When a failed node will become online again, logical replication should enable this node to recover, right?

Here are my questions:

#) Is this feasible or nonsense?
#) What would an alternatives for FreeBSD be (pgpool-II, repmgr, …)?

Any input is highly appreciated.

Thanks in advance and regards,
Michael


[1] 3 nodes, primary-primary replication.
[2] https://dbmail.org/en/
[3] All incoming MUA requests are directed to a single node in order to prevent split brain situations