Apparently somehow they managed to start 2 instances of MariaDB that ran concurrently and they were each locking the files for another and this error kept popping in the log: “Can’t lock aria control file ‘/var/lib/mysql/aria_log_control”
Very surprised to see this one, but appeared on a server where a junior admin made a mess of a database, so i was called in to help.
In order to fix, i had to stop the monitoring scripts, and the automatic SQL restart, then i checked for all MySQL running processes, killed them, and started the db properly, while verifying in the logs to see if anything got broken due to the abrupt interruption.
A good practice after this is to run a repair on all databases, to make sure everything is in order