| 摘要 |
PURPOSE:To fully devise a countermeasure against fault without deteriorating system performance by preventively maintaining a spare disk while I/O request against a master disk is received. CONSTITUTION:Two magnetic disk devices 11-1 and 11-2, two disk controllers 12-1 and 12-2 and CPU 14 are provided. The master disk is switched to the spare disk and the spare disk to the master disk after data is copied from the master disk to the spare disk and a fault countermeasure function for fault detection, recovery and prevention is executed against the disk device which is switched to the spare disk. Therefore, the spare disk is preventively maintained while I/O request as against the master disk is received. Thus, fault countermeasure is fully executed without deteriorating system performance. |
