Patent ID: 7467235

Claim:
A computer system for transferring data from a first storage unit in a storage system to a second storage unit in a backup storage system via a network, said computer system comprising: a first controller provided in the storage system, which transfers data stored in said first storage unit, to said second storage unit using a block transfer protocol; a storage area network (SAN) through which the transfer of data using the block transfer protocol is performed to said second storage unit; a table provided at a sewer coupled to the network, wherein the table associates a file composed of a plurality of blocks of data with blocks of data constituting the file; and a second controller provided at the server, wherein in response to information that identifies a particular data block to be transferred from said first controller via said SAN, identifies a file corresponding to the particular data block using said table and transfers the identified file to said second storage unit via, a local area network (LAN) using a file transfer protocol, wherein said SAN is configured to couple said first controller and said second controller and establish a path for data block transfer between said first storage unit and said second storage unit using the block transfer protocol between said first storage unit and said second storage unit and another path for file transfer between said first storage unit and said second storage unit using the file transfer protocol through the server and the LAN, wherein said table is provided in said second controller of the server and receives, from said first controller of the storage system, information indicating whether the particular data block has been transferred to said second storage unit of the backup storage system successflully in units of data blocks to allow said second controller to select the another path when the information indicates an unsuccessihi transfer of the particular data block.