Patent ID: 7398448
Filing Date: 2008-07-08
Classification: G06F

Abstract:
1. A storage system for saving host data handled by a host computer, comprising: a plurality of storage devices having a plurality of storage areas capable of storing data; a RAID controller that controls said plurality of storage devices by RAID technology, a write data receiving unit that receives host data instructed to be saved from said host computer as write data; a check code appending unit that generates a first check code having a relationship with said write data, and appends said first check code to said write data; a cache memory that stores said first check code; a write instructing unit that instructs said storage device on a write operation for writing said write data having said first check code, to a specified storage area among said plurality of storage areas; a read instructing unit that, after said write operation, instructs said storage device to read data stored in said specified storage area as read data; a check code generating unit that generates a second check code having a relationship with said read data; a writing check unit that checks a correspondence between said first check code stored in said cache memory and said generated second check code in order to determine whether said write operation has been done normally; a recovering unit that recovers data saved on a storage device for which error is detected by said writing check unit; and an overwriting unit that overwrites said recovered data onto said storage device for which error is detected.