I'm not sure how to explain this. Once one starts having dozens or hundres of servers, each running some sort of periodic jobs (mostly from cron), there is a problem of making sure (or as sure as possible) that these tasks are actually ran. I mean, I get an email if a job fails fails, and no mail if it succeeds, but also no mail if it doesn't run for whatever reason. Sure, I could change them and have them send a "successfully ran" email, only to be flooded by mails that most of the time I don't want to see.

Basically, I want to be notified only if:

• a task ran and failed
• a task didn't run at the expected time.

Is there a way to do this?