Abstract: Each of the storage devices 1, 2 is provided with transmission queues 306a, 306b with respect to each of transmission paths A and B. The storage device 1 stores identical request data in each of the transmission queues 306a and 306b, and transmits each data to the counterpart storage device 2, respectively via the transmission path A and B (S811, 812). The storage device 2, being a counterpart, stores the request data or response data arrived earlier in the receive history information table 300 (S817), and discards the request data arrived later (S903, 904). Furthermore, if the storage device 1, being a transmission source, receives at least one response data against the request data, the storage device 1 searches the transmission queues 306a, 306b, and if there remains request data in any of the transmission queue, deletes the request data (S909).

Abstract: A storage device (1) communicating with a host computer and other storage devices through a network is characterized in that the storage device (1) secures memory buffers for temporarily storing data in a remote copy operation carried out between the storage devices. A network memory (100) in the storage device (1) includes an available buffer comprising a plurality of memory buffers and an in-use buffer also comprising a plurality of memory buffers. A buffer control unit (215) secures memory buffers of the available buffer as a reserved buffer having a reserved-buffer size specified in a buffer reservation request made by a storage management device (8) in response to the request. The buffer control unit (215) then allocates the memory buffers of the reserved buffer as the in-use buffer in response to a request received from the storage management device (8) to start a remote copy operation.

Abstract: A storage device (1) communicating with a host computer and other storage devices through a network is characterized in that the storage device (1) secures memory buffers for temporarily storing data in a remote copy operation carried out between the storage devices. A network memory (100) in the storage device (1) includes an available buffer comprising a plurality of memory buffers and an in-use buffer also comprising a plurality of memory buffers. A buffer control unit (215) secures memory buffers of the available buffer as a reserved buffer having a reserved-buffer size specified in a buffer reservation request made by a storage management device (8) in response to the request. The buffer control unit (215) then allocates the memory buffers of the reserved buffer as the in-use buffer in response to a request received from the storage management device (8) to start a remote copy operation.

Abstract: In a computer system in which one or more computers on which one or more initiators operate and a storage device on which one or more targets operate are connected with each other through a network, an authentication table for authenticating validity of a user of a computer is associated with an authorization table for authorizing access of an initiator to a certain target, to limit such accesses.

Abstract: Each of the storage devices 1, 2 is provided with transmission queues 306a, 306b with respect to each of transmission paths A and B. The storage device 1 stores identical request data in each of the transmission queues 306a and 306b, and transmits each data to the counterpart storage device 2, respectively via the transmission path A and B (S811, 812). The storage device 2, being a counterpart, stores the request data or response data arrived earlier in the receive history information table 300 (S817), and discards the request data arrived later (S903, 904). Furthermore, if the storage device 1, being a transmission source, receives at least one response data against the request data, the storage device 1 searches the transmission queues 306a, 306b, and if there remains request data in any of the transmission queue, deletes the request data (S909).

Abstract: In a computer system in which a computer, storage devices, and a storage management device are connected by a network, the computer or a first storage device accesses a second storage device using a plurality of paths in the network, and the computer or the first storage device performs load balancing among the plurality of paths on the basis of a ratio set in advance, it is detected that congestion has occurred on a path, a ratio at the time of congestion of the path is calculated, and a difference between the ratio at the time of congestion and the ratio set in advance is allocated to a ratio of the other paths between the computer or the first storage device and the second storage device.

Abstract: In a computer system in which a computer, storage devices, and a storage management device are connected by a network, the computer or a first storage device accesses a second storage device using a plurality of paths in the network, and the computer or the first storage device performs load balancing among the plurality of paths on the basis of a ratio set in advance, it is detected that congestion has occurred on a path, a ratio at the time of congestion of the path is calculated, and a difference between the ratio at the time of congestion and the ratio set in advance is allocated to a ratio of the other paths between the computer or the first storage device and the second storage device.

Abstract: A storage device (1) communicating with a host computer and other storage devices through a network is characterized in that the storage device (1) secures memory buffers for temporarily storing data in a remote copy operation carried out between the storage devices. A network memory (100) in the storage device (1) includes an available buffer comprising a plurality of memory buffers and an in-use buffer also comprising a plurality of memory buffers. A buffer control unit (215) secures memory buffers of the available buffer as a reserved buffer having a reserved-buffer size specified in a buffer reservation request made by a storage management device (8) in response to the request. The buffer control unit (215) then allocates the memory buffers of the reserved buffer as the in-use buffer in response to a request received from the storage management device (8) to start a remote copy operation.

Abstract: In a computer system having a storage device, switches and hosts respectively connected by a network, in accordance with an ID of a logical volume of the storage device and an IP address of a host, access control configuration of the logical volume is performed relative to the storage device, the IP address of the host is converted into a MAC address, the MAC address of the host is converted into a port ID of the switch connected to the host, and addition of the port to virtual local area network (VLAN) is performed for the switch. Logical unit number (LUN) masking and VLAN configuration essential for security countermeasure of IP-SAN (Internet protocol-storage area network) can be managed collectively by a system administrator so that the running cost of IP-SAN can be lowered.

Abstract: A presence management apparatus connected to first and second apparatuses via a network includes a unit for updating a first user's presence received from the first apparatus and a second user's presence received from the second apparatus, wherein the first user uses the first apparatus and the second user uses the second apparatus; a unit for registering a matching condition for another user's presence received from the first apparatus and designated by the first user and a matching condition for another user's presence received from the second apparatus and designated by the second user; and a unit for deciding if the first and second user's presences match the designated conditions when registration processing and/or update processing is performed.