Why should we be the ones to look into it? It was a random intermittent short-duration fault in the middle if the Internet, at some unknown place on the then-current path between us and Pingdom. Why should not Pingdom be at least equally as obligated to look into it? After all, they’re the ones actually using the failing connection, in order to monitor our and others’ services. But no, Pingdom simply report us as being down, and leave the hard part to us; i.e. the part where we have to explain to our customers that the Pingdom report is actually provably incorrect.

I mean, what qualifies as “being up”? If some random link in the middle of the Internet goes down, and you suddenly, for 30 seconds, are unreachable for the few hundred people going through that exact link because it happens to be the best path between those people and your server, can they claim that you have failed to provide adequate uptime? If such a fault happens, are you then responsible to troubleshoot it? I say no. The Internet is the ISP’s responsibility, and the only faults actually meaningful to report to your ISP are the repeatable or long-lasting ones. Small stuff like this is not worth anybody’s time (except ISPs) to go digging into.

That was not the case with us; Pingdom would report short outages, like a few seconds here, a couple of minutes there, and only a handful of occurrences for the whole report duration (IIRC).