| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method to effectively restore data in the event of failure of two arbitrary storage devices. <P>SOLUTION: A main storage array comprises a plurality of connected sub-arrays, each of which comprises an assembly of data storage devices and a local parity storage device to store a value to be used for correcting a failure of a unitary device in a row of a block of the sub-array (eg. a row parity group). To each sub-array, a diagonal parity group is allocated as if it had been the only existence using a method of encoding for protecting against double failure. The main array further comprises a global diagonal parity storage device that holds a diagonal parity calculated by adding an equal diagonal parity group logically in a lump at each of the sub-arrays. <P>COPYRIGHT: (C)2004,JPO |
