The hot aisle is located adjacent to the cold aisle. The cold aisle layout is the most common starting point in data center design. Cold air is delivered into this aisle through: Servers pull this cold air into their front. The hot aisle /cold aisle data center layout was originated by IBM in 1992 and it is one of the oldest ways to save energy in the data center. We're essentially putting those servers back-to-back, we're putting them front-to-front, if you will, on these servers. And the cold air is moving up, and because it's the front of the server, the server is now pulling that. In this layout, server racks are arranged in alternating rows, with the fronts of servers facing each other (Cold Aisles) and the backs facing each other (Hot Aisles).
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