Patent ID: 7908418

Claim:
A storage system comprising: a host device; and a storage device connected to the host device through plural paths and including a disk unit and control modules, the control modules controlling data transmission and reception between the host device and the disk unit through the plural paths, the host device including; a command control unit to generate an inquiry command about whether to allow firmware exchange of the control module and to generate a status notification command about whether to allow the firmware exchange of the control module in each of the plural paths; a command transmitting unit to transmit the generated inquiry command and the generated status notification command to the storage device in each of the plural paths; a response information receiving unit to receive a response information that includes a predetermined firmware exchange order number of the control module from the storage device as a response to the inquiry command in each of the plural paths; and a connection control unit to request the command control unit to issue a state notification command to notify the storage device of an abnormal state when all of the firmware exchange order numbers in the response information received from the plural paths are the same, and to request the command control unit to issue the state notification command to notify the storage device of a normal state when at least one of the firmware exchange order numbers in the response information differs from another firmware exchange order number, and the storage device including; a receiving unit to receive the inquiry command and the status notification command from the host device; a response information generating unit to generate the response information including the predetermined firmware exchange order number of the control module to the received inquiry command; a transmitting unit to transmit the generated response information to the host device; and a firmware exchange control unit to not perform the firmware exchange of the control module when the abnormal state is notified, and to perform the firmware exchange of the control module in an order of the firmware exchange order numbers when the normal state is notified, in response to a request to start the firmware exchange from a user.