in reply to Parsing a specific section of a log file
File::Tail will help with that. You can write a continuously running process which monitors the log and reads new entries at an interval you select.
Just push the timestamp from success records onto an array, splice out all the timestamps over half an hour old, and warn if the array is empty.
As with any continuously running service, it would be a good idea to make a Daemon of it.
After Compline,
Zaxo
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