EXTERNAL STORAGE DEVICE, CONTROL METHOD, EXTERNAL STORAGE DEVICE SYSTEM, PROGRAM AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide an external storage device for restoring failure. SOLUTION: Each of a plurality of storage devices connected to each other through communication paths to form circular first paths is operable to invalidate a connection to a first preliminary communication path being a communication path of the first paths for performing communication, and is provided with a first connecting part having a first input part and a first output part and a second connecting part having a second output part and a second input part which are respectively connected to the first input part and the first output part of the external storage device adjacent on the first paths to form part of the first paths. When both connecting parts are valid, pieces of information received by the first input part and the second input part are respectively transmitted from the second output part and the first output part. When any connecting part is invalid, the information received by the input part of the valid connecting part is transmitted from the output part of the connecting part. When the failure of any communication path on the first paths is detected, the connection to the first preliminary communication path is validated, and the connection to the communication path whose failure is detected is invalidated. COPYRIGHT: (C)2003,JPO