Re: Are you sure they were servers?
I once unplugged one of the six power cables going into an HP blade enclosure and the entire thing powered off. Thirty seconds later I was having to deal with an irate boss, but he did calm down and agree that they were specifically supposed to be redundant PSUs, and so perhaps it wasn't entirely my fault.
We eventually traced it to a bad PSU that would only take about 20% of it's rated load before failing. Thanks HP.
Biting the hand that feeds IT
