We have Nagios XI 5.9.3, it was updated back in March-2023. But a week ago, the nagios.log files went from 3MB to 3.5GB daily. This filled up the disk space.
The nagios.log (and archives for the last week) have a lot of the following messages for different service-checks.
 NDO-3: The following query failed while MySQL appears to be connected:
 NDO-3: INSERT INTO nagios_servicechecks (instance_id, start_time, start_time_usec, end_time, end_time_usec, service_object_id, check_type, current_check_attempt, max_check_attempts, state, state_type, timeout, early_timeout, execution_time, latency, return_code, output, long_output, perfdata, command_object_id, command_args, command_line) VALUES (1,FROM_UNIXTIME(1683950399),928343,FROM_UNIXTIME(1683950400),92623,7681,0,1,3,0,1,120,0,0.164280,0.000000,0,'DISK OK - free space: / 39612 MB (81% inode=92%):','','/=9049MB;38928;43794;0;48661',0,'','') ON DUPLICATE KEY UPDATE instance_id = VALUES(instance_id), start_time = VALUES(start_time), start_time_usec = VALUES(start_time_usec), end_time = VALUES(end_time), end_time_usec = VALUES(end_time_usec), service_object_id = VALUES(service_object_id), check_type = VALUES(check_type), current_check_attempt = VALUES(current_check_attempt), max_check_attempts = VALUES(max_check_attempts), state = VALUES(state), state_type = VALUES(state_type), timeout = VALUES(timeout), early_timeout = VALUES(early_timeout), execution_time = VALUES(execution_time), latency = VALUES(latency), return_code = VALUES(return_code), output = VALUES(output), long_output = VALUES(long_output), perfdata = VALUES(perfdata), command_object_id = VALUES(command_object_id), command_args = VALUES(command_args), command_line = VALUES(command_line)
I see a similar thread, but dont see any solutions.
Any suggestions would be greatly appreciated. I also ran the repair database and that didnt show any issues. I have also restarted the system.