Recently I had the problem that mosquitto‘s status was “active (exited)” – therefore no MQTT messages got handled and transferred to my local influx database instance.
Even restarting the service did not help.
After some tinkering around I found out: obviously the server did an unplanned reboot (power failure) and therefore mosquitto’s database got damaged. I did not even try to find a fix on how to repair (feel free to add a comment) – I just deleted the db-file.
After that, mosquitto is up and running again.