Patent ID: 6604172
Filing Date: 2003-08-05
Classification: G06F

Abstract:
A disk array apparatus for storing data used for a higher level device, comprising:a plurality of disk drives for storing write data from said higher level device and storing redundant data used for the data of a data group to which the write data from said higher level device belongs; a disk control device for transferring the write data between said higher level device and one of said disk drives; a redundant data generating circuit present in said disk control device, for generating new redundant data from either (1) the write data from said higher level device, old data to be updated by the write data, and redundant data of the data group to which the write data belongs, or (2) the write data from said higher level device and data not to be updated by the write data of the data group to which the write data belongs; and a processor present in said disk control device capable of selecting an operation of said redundant data generating circuit in accordance with at least whether the one of said disk drives for saving said redundant data is in use.