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

shammat@gmx.net wrote:
> Am 22.05.26 um 15:18 schrieb Michael Grimm:

>> 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].
> 
> For such a system I don't see the need for a multi-master setup (neither
> with Postgres nor with MariaDB).

What I didn't mention in my mail is: incoming mails at all three mail servers become stored into each user's mailbox  at the server they arrive (LMTP). In this scenario multi-master is handy.

But see below.

> For high availability you don't need multi-master. A standard
> streaming replication with a failover mechanism is completely enough
> in my opinion.

Thanks for this hint w.r.t. streaming replication.

I have made some research about this kind of cluster and come to the conclusion that streaming replication plus repmgr [1] will meet my expectations.

BUT: I will need to configure haproxy to route all IMAP and LMTP traffic to the "current" master, only. 

I am hoping that this can be achieved by a customised health check plus routing, but I have never done that before, though.

Thanks and regards,
Michael



[1] available in the FreeBSD ports collection