A power outage that took out Unisys' Penrose data centre in Auckland, New Zealand, for an hour illustrates the unfortunate impact of rare but not impossible coincidences. Although the mains power was out, the datacentre had sensibly rented a standby generator to provide cover whilst installing a new genny. That should have been enough to keep the UPS topped up ... except for a coincident problem with water in the standby genny's diesel fuel supply. How many times have we read about power works causing computer room outages? (And to be fair, how many more have taken place without incident?).
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