Abstract: A system for monitoring performance of an intelligent array expansion system includes a controller for communicating with a host computer and associated intelligent array expansion systems, each of which has a plurality of fixed disk drives. The controller incorporates firmware to monitor a plurality of predetermined performance data, such data being thereafter stored in information storage devices. At the same time counts are maintained for selected parameters which are of interest to a systems manager. Such counts and the performance data are stored for each one of a plurality of preselected intervals, and an indication or warning is given to the systems manager when performance data, or when a selected parameter exceeds a preselected threshold.

Abstract: A method for automatically remapping a disk after receiving a bad sector indication without requiring system operator intervention, initiation of a diagnostic program or system down time. When the disk controller receives the error and mirroring or parity operation is activated, a remap routine is initiated. The routine finds the bad sector in the request, builds a good track of data and stores this good track of data in a reserved area on all the disk units on the controller. The data in the reserved area is then read, and if successful, the track having the bad sector is remapped to remove the bad sector from use. The saved data is then rewritten to the track, thus restoring the disk unit to full operation. A flag is set during the process so that should power fail the process can be restarted.

Abstract: Temperature sensors are located inside drive chambers where disk drives are located to signal an overheating condition. An overheating condition triggers external alarms and produces an interrupt signal to the disk drive controller, which, in turn, alerts the operating system. If the operating system does not comprehend the problem and take the appropriate action, the controller shuts down the disk drives after a certain period of time.