I do remember one time I had to take down Server A and to make sure everything was correct I took the opportunity to turn off the UPS and then go around the back and disconnect Server A's UPS from the mains socket.
Beep beep beep went Server B's UPS. Glad I caught that before a real problem happenned, I swapped the plugs to the correct sockets and nobody knew that had happenned.
Biting the hand that feeds IT
