Unable to configure wsrep_gtid_domain_id through config file when cluster is operational

Hi,

I tried to configure wsrep_gtid_domain_id on a running cluster:
I changed the configuration file and restarted MariaDB.

After restarting, the wsrep_gtid_domain_id remained 0. According to both SHOW GLOBAL VARIABLES and the GTID position (after changing some data).

When I stopped the other 2 nodes and restarted 1 node with the configuraiton change the new configuration showed up in SHOW GLOBAL VARIABLES.

It DID work to change the configuration with SET GLOBAL, so it seams that Galera does allow different configuration of wsrep_gtid_domain_id.

Steps to reproduce:

• Set up a cluster (wsrep_gtid_domain_id set to the default) with at least 2 nodes (I tested with 2 nodes and 1 arbitrator but I expect the behaviour to be the same on a 2 node cluster)
• Change the configuration file on 1 node and restart that node
• Verify that wsrep_gtid_domain_id is 0

Is this a bug, or intended behaviour? To me it is very unexpected that it does not work to specify a configuration in the configuration file, but that it does work using SET GLOBAL. If it is intended behaviour, the documentation should be updated.

Thank you,
Michaël