This sort of service-oriented monitoring is very close to the pain point that caused us to create Cabot. In our case, it was more that there were multiple thin

This sort of service-oriented monitoring is very close to the pain point that caused us to create Cabot. In our case, it was more that there were multiple things we could monitor for that potentially indicated a problem with a service but it was hard, using Nagios or whatever, to tie those individual indicators back to a single service going haywire at 3am, especially if all 50 of them blow up at once. We don't have the precise problem that you describe though - for us the ability to monitor the number of data series in a graphite collection (so that if a server disappears we can notify, and then if another drops off we can alert) is sufficient. Cabot can use this and the ability to tolerate a number of failures to give behaviour very close to what you talk about. However I don't know if Cabot would support the kinds of checks that you're carrying out out-of-the-box, you'd probably have to extend.