Patent ID: 6993625

Claim:
A disk storage system comprising: a first plurality of disk drives storing data; a second plurality of disk drives storing data; a first loop used to transfer data to said first disk drives; a second loop used to transfer data to said disk drives; a first plurality of communicating lines coupling said first loop with said first disk drives and coupling said first loop with said second disk drives; a second plurality of communicating lines coupling said second loop with said first disk drives and coupling said second loop with said second disk drives; a first plurality of connecting parts coupling said first communication lines and said second communication lines with said first disk drives; a second plurality of connecting parts coupling said first communicating lines and said second communicating lines with said second disk drives; a disk controller comprising: a first disk communicating port coupled to said first loop, and communicating with said first disk drives via said first loop, a second disk communicating port coupled to said second loop, and communicating with said second disk drives via said second loop, a host communicating port communicating with a host unit, a cache memory storing data, which is communicated between said host communication port and said first and second disk communicating ports, and a processor controlling said host communicating port, said first disk communicating port, said second disk communicating port and said cache memory.