Monitor an app

[@lbutlr]

Are there any tools that monitor apps or services and do sane things to make sure that the series are running?

Obviously, I can write a simple script that says something like "if service <name> status doesn't have a PID, then …" but that's simplistic and I don't want something that is simply going to restart a failed service over and over every time it crashes. (But once or twice when it crashes is good, with an escalation to maybe restart a different series and a fall back from that to restart the machine… but again, not restarting the machine a few seconds after boot because it can't start the service.)

I am not looking for something that says "hey, email is not working" (I already have that but more subtly like "Hey, dovecot isn't running" or "MySQL isn't running".

Googling leads me to external monitoring of forward facing services based on port scanning, I'm looking for something local to the machine.



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IT'S BECAUSE OF THE UNCERTAINTY PRINCIPLE. 'What's that?' I'M NOT
	SURE. --The Fifth Elephant