In a storage system directly connected to a network, if conventional interfaces and protocols are used when an I/O command issued from a file server is transmitted to the storage system, the command/data is serially transferred via a single transfer path so that the performance is lowered. Conventional interfaces do not provide the means to notify the storage system of the failure at the file server. The file server and a channel adapter of the storage system are mounted on the same board and connection paths therebetween are controlled so that a plurality of protocols can be operated independently. A path independent from a command/data path is provided between the file server and channel adapter, and the received failure information is stored in a shared memory of the storage system and used for the fail-over.