logfile content check sensor

Use a batch file

If your log file is the result of a backup job, there is most likely an option to run a batch file after the completion of the job. In this batch file, copy the log file to a file with a fixed name.

copy "your_log_file" c:\temp\checkthis.txt /Y

and have the sensor check the "c:\temp\checkthis.txt" file.

This way the file will always exist and the sensor will not return an error.

More advanced solution

There is a small catch in the solution above. If the file contains text that should trigger the sensor and the sensor is already triggered by the previous version of the "c:\temp\checkthis.txt" file, notifications will not be send again.

To overcome this, we first need to make sure that the "c:\temp\checkthis.txt" file contains no text that triggers the sensor and force the sensor into an OK state by running the sensor.

The new batch file will now look something like:

rem ** create a file that will not trigger the sensor **
echo The sensor will not trigger on this text > "c:\temp\checkthis.txt"
rem ** force the sensor to run using cUrl **
curl yourPRTGserver/api/scannow.htm?id=objectid&login=user&password=password 
rem ** wait for 5 seconds **
ping 1.1.1.1 -n 1 -w 5000 > NUL
rem ** copy the log file **
copy "your_log_file" c:\temp\checkthis.txt /Y

Replace objectid with the ID of your sensor.