MyBB Community Forums

Greetings,

I have a problem with my installation of myBB in connection with a Load Balancer.

I would like to use a SQL cluster (Galera Cluster) as a DB, but when my myBB tries to connect with two of the three Cluster server, I always get the Error 42. This happens only on two of the three cluster server.

short information:

- Running the newest myBB 1.8.19
- Running MySQL Ver 14.14 Distrib 5.6.41, for Linux (x86_64)
- Running apache2 with php7.0
- I'm using Galera Cluster as the Cluster-Software.
- The connection with the cluster is over a Loadbalancer (HAProxy).
- All of the servers are virtual.

I tried for Error42 and upgraded via /install but the error messages remain anyway.

I also tried the way out of the documentation for MyBB 1.6 and entered the servers manually into the Conifg.php with [read] and [write]. This also fails.

And yes I know that the cluster is unnecessary for a small forum. But I have to do this installation for the university as a project.

Does anyone have an idea where the error is?

Thanks!

php.config:
[attachment=41452]

error 42:
[attachment=41451]

OK, that error message says more than you think. When you upgraded your forums, it upgraded one node of your cluster. How does Galera handle schema changes? You might need to dump (eg. do a backup) of your good node and restore it to your other two nodes. I'll let someone with more clustering experience more fully answer.

BTW, is one node set up as a "master" and the other two nodes replicate off that master? If so, some code changes might be needed for a "read" connection and "write" connection.

Thanks for the answer,

To be sure that it is not due to the cluster, I have completely rebuilt it. Unfortunately, exactly the same error comes again with Error42. The cluster nodes are all "healthy".

Galera Cluster is a Multi-Master Cluster. Each node has read and write access. So that can not be the problem.