Abstract: An information processing system comprises a plurality of information processing devices; and a fault-tolerant power distribution system comprising a plurality N+1, wherein N is greater than 1, removable power supplies for providing power to the system, N power supplies being sufficient to provide power to the plurality of devices; and a plurality M removable power distribution units for connecting the power supplies to the devices, the connection of the power supplies with the power distribution units being configured such that on removal of either of the units, the remaining unit is still connected to N of the power supplies to thereby maintain power to the system.

Abstract: A cooling system provides redundant fault-tolerant cooling to electrical devices in an electrical apparatus and comprises a plurality N+1 individual cooling fans, N cooling fans being required to provide cooling of the devices and further comprises monitor logic for monitoring the status of the plurality of cooling fans and for issuing a non-critical warning to the apparatus in the event of failure of one of the cooling fans, the logic being further operable, in the event of a failure in the logic, to issue a non-critical warning to the apparatus.

Abstract: A modular housing for first and second groups of replaceable functional units, e.g., disk files comprises a chassis for supporting the units within a first compartment extending along the length of a chassis support structure and removable via opposite openings in the chassis. Replaceable cooling and power supply assemblies are located within a second compartment of the drawer and can be removed from drawer via one of the openings without removing either of the groups of functional units. The fan of a combined cooling and power supply unit is arranged centrally within the second compartment such that it draws cooling air past the first group of units and exhausts air towards the second group of units.