Maintenance Strategies for the Infrastructure of Cloud Data Centers: a case study

Over the past thirty years there has been a signifi­cant change in the concept of Data Center, which have evolved to accommodate the increasing needs of users, but the common denominator is now recognized as power and cooling. A typical mid-size Data Center has now a number of com­pute servers of the order of a couple of hundreds, and storage tor several petabytes, but modern technology hardware use a lot of electrical ener­gy and dissipate a lot of heat. In addition, Data Centers need to be properly maintained without interruption, to previde continuous services to web users. Server tor Artificial lntelligence applications work with power-consuming GPU's, thus leading to a distributed liquid-based cooling system, rath­er than an air-based one. Water pipes and elec­tricity directly connected to IT hardware pose big maintenance problems. Proper maintenance strategies have to be formu­ated for an efficient Data Center with a sustaina­ble Power Usage Effectiveness parameter, that is reducing the energy devoted to cooling only, and this paper describes a case-study at the university Federico Il, in southern ltaly,where a 1 Mwatt Data center is maintained operational and efficient over two decades now, with a complete, distributed monitoring system and a particular attention to the power and cooling system.