Patent ID: 6993636

Claim:
A data storage system comprising: an original channel unit coupled to an original host; an original disk control unit coupled to said original channel unit for controlling writing process of data received from said original host; an original disk unit coupled to said original disk control unit for storing data according to control of said original disk control unit; a sub-channel unit coupled to a sub-host; a sub-disk control unit coupled to said sub-channel unit and said original disk control unit for controlling writing process of data received from said sub-host and said original disk control unit; a sub-disk unit coupled to said sub-disk control unit for storing data according to control of said sub-disk control unit; wherein said original disk control unit realizes data duplexing of original disk unit and sub-disk unit by sending written data received from said original host to said sub-disk control unit, and wherein said original disk control unit sends a plurality of written data received from said original host during certain period to said sub-disk control unit, and does not send written data included in a plurality of written data received from said original host during other certain period to said sub-disk control unit.