METHOD, SYSTEM AND MEDIUM FOR SELECTING DESIRABLE PASS TO STORAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method, a system, a program, and data structure for selecting a pass at least to either one of two controllers. SOLUTION: Pass information indicating a desirable controller to be used for accessing respective storage areas is received from a controller. An input/ output(I/O) command sent to a target storage area is sent to a controller indicated as the desirable controller for the target storage area in the pass information. The pass information to the storage area controller for providing an access to a storage area is encoded by information for specifying one controller as a desirable controller and the other controller as an undesirable controller. The encoded pass information is returned to a request side computer. The request side computer sends the I/O command to the desirable controller at first, and when the desirable controller can not execute the I/O command, sends the I/O command to the undesirable controller.