a first interface for receiving an access request from a host device issuing said access request;

a second interface for respectively accessing one or a plurality of access destination candidates in an external device provided with said one or a plurality of access destination candidates via a network,

wherein said second interface:

attempts, when said first interface has received an access request, access to a particular access destination candidate in the external device corresponding to the received access request via said network, of said one or a plurality of access destination candidates;

judges that a fault has occurred and outputs a judgment result indicating a fault, if said access attempt fails; and

outputs a judgment result indicating a recovery if it is judged that there has been a recovery after the access attempt has failed, and

wherein said first interface determines that there has been a recovery in the access oath to said particular access destination candidate by referring to the judgment result output by the second interface,

wherein the first interface comprises:

a first processor which receives said access request from said host device and outputs another access request based on said received access request; and

a second processor which receives the other access request output by said first processor, and outputs yet another access request in order to request said second interface to access said particular access destination candidate of said one or a plurality of access destination candidates in the external device, based on said received other access request,

wherein said second processor refers to said judgment result and outputs a reference result indicating whether there is a fault or a recovery,

wherein said first interface has a second storage region which stores recovery existence data indicating the existence or absence of a recovery in the access path to each of said one or a plurality of access destination candidates,

wherein said second processor sets the existence of a recovery in said recovery existence data relating to said particular access destination candidate having a recovery,

wherein said first processor determines the existence of a recovery and recognizes said particular access destination candidate corresponding to the existence of a recovery, by referring to said recovery existence data,

wherein said second processor sets a second interrupt relating to said first processor, when it has determined that there has been a recovery from said judgment result, and

wherein said first processor detects said second interrupt and refers to said recovery existence data in response thereto.