What is the maximum number of master servers in a multi-source replication?

carlos pirez

New Member
Hello Friends,

Recently I deployed a multi-source replication scheme with over 100 master servers against a single slave. I had no problem with the setup despite, according to the documentation (https://mariadb.com/kb/en/mariadb/multi-source-replication/) the maximum number of nodes was 64.

I was wondering whether this limit was expanded in recent releases, but I could not find any further mention to it in the release notes.

However, I am having some spurious replication issues. For example, there are missing rows in the slave database. These missing rows come from random master servers. I would like to confirm with you that the limit of 64 servers was in fact expanded in version 10.1.22 (or prior) of MariaDB, running on a 64-bit Centos, so I can discard this as a possible cause for the problem we are experiencing.

I appreciate very much your time and help with this issue.


I've never gone past 4, personally.

I'd imagine where you'd start having issues with going so high would be related to auto-increment values. For every server you add, the space between auto-increments grows by that much more but with how it's built the number of servers theoretically could never cause a clash, except perhaps during the adding process.

It might just fall under the "too many chiefs, not enough indians" saying that you can only have so many masters. I'm honestly not sure.

Out of curiosity, why do you need so many masters?