Patent ID: 9652165
Date: 2017-05-16
CPC Classifications: G06F

Claim:
1. A plurality of storage subsystems connected via a network to a plurality of mainframe host computers, comprising multiplex volumes provided with identical identification information among the plurality of storage subsystems as volume identification information provided to the host computers; wherein the plurality of storage subsystems comprises, at least, a first storage subsystem for executing an extent exclusion processing with respect to the multiplex volume and a second storage subsystem other than the first storage subsystem, and control units provided to the respective subsystems; wherein the host computer transmits a channel command requesting input/output processing of data by a command chain configuration; and wherein the control unit of any of the plurality of storage subsystems obtain information on the multiplex volume being a target of the input/output processing from a beginning channel command of the command chain, if itself is the first storage subsystem, then executes the extent exclusion processing as well as an input/output processing by a subsequent command of the beginning channel command, with respect to the multiplex volume being the target of the input/output processing, and cancels the extent exclusion after the execution; and if itself is the second storage subsystem, then requests the extent exclusion processing with respect to the multiplex volume being the target of the input/output processing to the first storage subsystem, receives a result of the exclusion processing, executes an input/output processing with respect to the multiplex volume by a subsequent command of the beginning channel command based on the result, and notifies cancel of the extent exclusion to the first storage subsystem after the execution.