A computer system, comprising: a server module; a storage module; and a coupling module, wherein the server module comprises: a first processor; a first memory; a first interface for coupling to other devices; a storage access part for requesting access to the storage module via the first interface; a failure detecting part for detecting a failure in the first interface; and a failure processing part for executing given recovery processing when the failure detecting part detects a failure in the first interface, wherein the coupling module comprises: a first end point which is connected to the first interface and, when detecting a failure in the first interface, outputs a failure notification; a second end point which is connected to a second interface of the storage module; a data transfer part for transferring data between the first end point and the second end point; and an event imitation part for converting the failure notification into a notification of disconnection of the first interface when the first end point outputs the failure notification, and transmitting the disconnection notification generated by the conversion to the storage module from the second end point, and wherein the storage module comprises: a second processor; a second memory; a storage device; the second interface for coupling to other devices; a storage control part for receiving an access request through the second interface and accessing the storage device; and a disconnection processing part for disengaging coupling to the server module when the disconnection notification is received from the coupling module. a server module; a storage module; and a coupling module, wherein the server module comprises: a first processor; a first memory; a first interface for coupling to other devices; a storage access part for requesting access to the storage module via the first interface; a failure detecting part for detecting a failure in the first interface; and a failure processing part for executing given recovery processing when the failure detecting part detects a failure in the first interface, a first processor; a first memory; a first interface for coupling to other devices; a storage access part for requesting access to the storage module via the first interface; a failure detecting part for detecting a failure in the first interface; and a failure processing part for executing given recovery processing when the failure detecting part detects a failure in the first interface, wherein the coupling module comprises: a first end point which is connected to the first interface and, when detecting a failure in the first interface, outputs a failure notification; a second end point which is connected to a second interface of the storage module; a data transfer part for transferring data between the first end point and the second end point; and an event imitation part for converting the failure notification into a notification of disconnection of the first interface when the first end point outputs the failure notification, and transmitting the disconnection notification generated by the conversion to the storage module from the second end point, and a first end point which is connected to the first interface and, when detecting a failure in the first interface, outputs a failure notification; a second end point which is connected to a second interface of the storage module; a data transfer part for transferring data between the first end point and the second end point; and an event imitation part for converting the failure notification into a notification of disconnection of the first interface when the first end point outputs the failure notification, and transmitting the disconnection notification generated by the conversion to the storage module from the second end point, and wherein the storage module comprises: a second processor; a second memory; a storage device; the second interface for coupling to other devices; a storage control part for receiving an access request through the second interface and accessing the storage device; and a disconnection processing part for disengaging coupling to the server module when the disconnection notification is received from the coupling module. a second processor; a second memory; a storage device; the second interface for coupling to other devices; a storage control part for receiving an access request through the second interface and accessing the storage device; and a disconnection processing part for disengaging coupling to the server module when the disconnection notification is received from the coupling module.