Data storage system and method for managing asynchronous attachment and detachment of storage disks

摘要

A disk array data storage system (14) has plural sets of storage disks (70-80) connected to multiple corresponding I/O buses (64-67). Individual storage disks can be independently and asynchronously attached to or detached from corresponding interfacing slots (50-61) of the I/O buses. The system has physical device drivers (92) which represent the storage disks with respect to their connections to the interfacing slots of the I/O buses and physical device managers (94) which represent the data kept on the storage disks. Interface drivers (90) are provided to manage I/O transfers through corresponding I/O buses. When a particular storage disk (80) is attached to or detached from an interfacing slot (55) of an I/O bus (65), the interface driver (90) corresponding to the I/O bus freezes all I/O requests that come from the physical device drivers (92) that represent the storage disks in the set connected to the I/O bus. A configuration manager (96) determines which interfacing slot (55) the particular storage disk has been attached to or detached from. If the particular storage disk has been detached from the I/O bus, the configuration manager (96) eliminates the physical device driver (92) that represents the detached storage disk. The data stored on the detached storage disk is rebuilt using redundancy on the remaining disks. If the particular storage disk has been attached to the I/O bus, the configuration manager (96) creates a new physical device driver (92) to represent the attached storage disk. The I/O requests to the I/O bus are then unfrozen. <IMAGE>