The storage comprises a first bridge, a second bridge that can be connected to the first bridge, a first storage device that can be connected to the first bridge, and second and third storage devices that can be connected to the second bridge. If a command that has been received from a main controller is a command not corresponding to the first storage device and an access destination of the main controller is the second bridge, a controller transmits a command corresponding to the received command to the second bridge. In contrast, if the command that has been received from the main controller is a command corresponding to the first storage device, the controller transmits the command corresponding to the received command to the second bridge or the first storage device.