| 摘要 |
A disc array system has a plurality of disc storage devices (i.e., drives) constituting a parity group and mounted in a distributed manner on different boards. Where any one drive in the same parity group develops a fault, the board carrying the faulty drive is withdrawn from the mother board for repair. If the CPU issues a write request for data held in the faulty drive or in any normal data on the same board, the requested data is recovered from the multiple data retained in the other drives constituting the same logical group and mounted on the other boards. The recovered data is sent to the CPU. If the CPU supplies write data to the faulty drive or to any normal drive on the same board, the supplied write data is held temporarily in a cache memory in an array controller. Later, when the board is repaired and replaced onto the mother board, the data to be held in the alternate drive having replaced the faulty drive is recovered from the data in the other drives, and the recovered data is written to that alternate drive. Then the write data in the cache memory is written to the alternate drive or to the target normal drive. <IMAGE> |
