When I visited the data center for 1&1 Internet, a huge hosting and cloud services provider located in Lenexa, Kan., I was struck by the size of the emergency generating system. The Caterpillar diesels that power the generators are the size of locomotive engines.
The four generator sets power the 40,000 servers in an N+1 configuration, and they provide the power to operate the cooling and other building services necessary to keep the data center alive when the power goes out. N+1 refers to a widely used practice in IT to allow for at least one extra system or a set of systems that will serve as a backup in case of failure.
It's all on a grand scale. The rows of server racks seem to go on forever, networking equipment rooms line each side of the building. The main hallway of the building seems to stretch into infinity. In short, 1&1's data center is one big place.
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