A blade server apparatus including a plurality of server modules, a backplane for mounting the plurality of server modules thereon, and an SMP coupling device having wiring lines to SMP couple the plurality of server modules. Each of the server modules has one or more processors controlled by firmware and a module manager for managing its own server module, the module manager has an ID determiner for informing each processor of a processor ID, each processor has a processing unit and an SMP virtual connecting unit for instructing ones of wiring lines of the SMP coupling device through which a packet received from the processing unit is to be transmitted, and an ID converter for converting the processor ID and informing it to the SMP virtual connecting unit is provided within the firmware.