Evaluating the cooling subsystem availability on a Cloud data center

A data center is divided into three basic subsystems: information technology (IT), power, and cooling. Cooling plays an important role related to data center availability, and a failure in this subsystem may cause an interruption of services. Generally, a redundant cooling subsystem is implemented based on replacing the failed component by the standby one. However, it also can be based on a rotation of computer room air conditioners (CRACs). This paper proposes scalable models that represent the cooling subsystem behavior to evaluate the impact of cooling failures on the data center availability. Models are based on the TIA-942 standard and represent Tiers I and II. We validate our model by comparing our results with the literatures. Our results show that the CRACs' rotation has similar results in availability when compared to the replace strategy.