Abstract: A status display system for storage device includes at least one logic device each having a plurality of physical device; and a plurality of device control means for controlling operations of the physical devices corresponding to a designated logic device in parallel in accordance with command from a host device. Preferably, the status display system is provided with status information generating means for collecting commands given to the device control means and responses to the commands given from the device control means, and generating a status information for the logic device; and display means provided corresponding to the logic device for displaying the status information in accordance with the generated status information.

Abstract: A disk array system includes a disk array, an array controller, an offtrack detecting unit, an error processing unit, an offtrack measuring unit, a reformat control unit, and a reformat processing unit. The disk array includes a plurality of disk devices storing a plurality of data in parallel and storing redundant data used for restoring data lost if one of the plurality of data is lost. The array controller controls input from or output to the disk array based on a request from an upper system, such as a host computer. The offtrack detecting unit is provided in each of the disk devices for detecting offtrack and informing the array controller of the offtrack. Further, an error processing unit is provided in the array controller for logically disconnecting a disk device having communicated information if offtrack detection information is received from the offtrack detecting unit, and for issuing a diagnostic I/O command.