Some hours ago a number of jobs (chains) failed @ nightly. The problem were database connectivity @ worker01.test.in.moodle.com.
Connected, there were no containers running and it seems the server was rebooted 19h ago:
So I've proceeded manually to kill exited (old) containers and start all the databases, using /store/scripts/dockercleaner.sh and /store/scripts/dockerdb.sh mysql|pgsql|mariadb|oracle|sqlsrv.
This issue is about to ensure that the scripts above are executed on startup to get everything ready or start (and maybe also to understand why the server was rebooted 19h ago).