I have a very simple process to be done.
We have plenty of Centos servers that are currently monitored by Nagios. Need to monitor one more metric.
Each of them has a script that creates the TXT file like bellow:
20190731 16:17: 15241 , OK: AD XXX user available
20190731 20:17: 14912 , OK: AD XXX user available
20190801 00:17: 14842 , OK: AD XXX user available
20190801 04:17: 14701 , OK: AD XXX user available
20190801 08:17: 14631 , OK: AD XXX user available
20190801 12:17: 14575 , OK: AD XXX user available
I need to take the date/time and those numbers marked red, show it in Nagios and put to the nagios grapher to show how it floats/peaks.
I already have check_log on each server but no idea how to use it and if its suitable for my needs.
Would be also nice to set some treashold.
Can i ask you for some hint?
More detailed more appreciated

Thanks in Advance