Provided is a storage control unit capable of, even when a failure occurs in access from a control unit to storage devices and the access from the control unit to the storage devices is switched to access via an alternate path, continuing I/O access to the storage devices without interrupting I/O requests from a host.The present invention provides a storage control unit having dual control units wherein a controller in one control unit, that has received an I/O request from a host, issues an I/O request to an initiator in another control unit using a control path between the controllers in the control units, and the initiator that has received this I/O request accesses the target storage device(s) via a connection path based on that I/O request.