Abstract: In a memory apparatus, there are provided a mirror primary LU which is a memory region on a plurality of storage media formed of nD+1P, a mirror secondary LU that is a memory region on a plurality of storage media formed of mD+1P, an n-RAID control subprogram for performing RAID control of nD+1P, an m-RAID control subprogram for performing RAID control of mD+1P, and an LU mirror subprogram for performing writing into the mirror primary LU and mirror secondary LU and then effectuating duplexing or “mirroring” when a computer issues a data write request. The “m” and “n” are different integers more than or equal to 2.

Abstract: For providing a storage control unit to be connected to a fiber channel, in which a new storage control unit is added onto the fiber channel network during on-line operation and succeeds control information of a logical unit from the storage control unit which has been existing before, so as to be in charge of a process request issued to that logical unit from a host computer thereafter, wherein a control memory being able to memorize the control information is provided in each of the storage control units 30 and 40, which information is necessary when succeeding or taking over the logical unit and is represented by such as construction information of a magnetic disk drive within a disk drive unit 20 and construction information of the logical unit, so on. The contents of the control memory within the storage control unit 30 is copied into the control memory of the storage control unit 40 when the new storage control unit 40 is added onto the fiber channel network.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: For providing a storage control unit to be connected to a fiber channel, in which a new storage control unit is added onto the fiber channel network during on-line operation and succeeds control information of a logical unit from the storage control unit which has been existing before, so as to be in charge of a process request issued to that logical unit from a host computer thereafter, wherein a control memory being able to memorize the control information is provided in each of the storage control units 30 and 40, which information is necessary when succeeding or taking over the logical unit and is represented by such as construction information of a magnetic disk drive within a disk drive unit 20 and construction information of the logical unit, so on. The contents of the control memory within the storage control unit 30 is copied into the control memory of the storage control unit 40 when the new storage control unit 40 is added onto the fiber channel network.

Abstract: High-purity alkanolamines, whose iron content is less than 50 ppb, are provided. Said high-purity alkanolamines can be produced by covering with an alkanolamine-resistant material at least a part of the inner wall of equipment that contacts alkanolamines from the top of the distillation tower to the storage tank in producing a high-purity alkanolamine from a crude alkanolamine by using distillation towers.

Abstract: An administrator is required to prepare in advance LU as a pool area when a user storage area is set to a storage. LU configuration is generally cumbersome and it is not easy for a general user to configure it. A pool manager 1 and a storage 1 setting utility in a management console 1 communicate with a program in a storage 1. The storage 1 sets a pool area having a designated capacity. In response to a volume forming request from the management console 1, the storage 1 sets a designated volume by setting the designated volume as a used capacity of the set pool area. When a volume is formed, a policy is designated to select a storage area having a corresponding attribute from the pool area.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: In an external storage, an I/O process is continued without any intervention of a user or a host system at failure of a controller. When a failure occurs in a controller, a host system recognizes the failure of the controller. Before the failure is notified to the user and application to stop the job, the substitutive controller reads the SCSI-ID possessed by an SCSI port of the failed controller from a shared memory, registers the SCSI-ID of the SCSI port to the SCSI port associated with the substitutive controller, and erases by a port address resetting facility of the substitutive controller the SCSI-ID possessed by an SCSI port of the failed controller.

Abstract: In order to enable an area of each logical volume to be expanded while continuously using the logical volume and to integrate separate logical volumes in a single continuous area, a storage has logical volume control means for controlling the construction of a logical volume, a logical volume number map in which logical volume construction information is described, and copy means for copying the logical volume. By allowing two or more inner logical numbers to be described per external logical number in the logical volume number map, improved flexibility in combining the logical volumes in the storage is achieved. By copying a plurality of separate logical volumes into a physical continuous area by the copy means, the logical volumes are integrated.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: RAID information and physical position information of hard disk units are managed by a disk controller in a mapped fashion. When the physical position of the hard disk units is changed, the information mapping is retried. Further, the positional information of the hard disk units accommodated in a disk array system under the administration of the disk controller, is calculated so as to form n-dimensional coordinate system information, and the resulting information is stored in each of the hard disk units. When the hard disk units are inserted into the disk array system, the n-dimensional coordinate system information is read from each hard disk unit. If it is detected that there is difference from the current coordinate system information, then information before removal and that after the insertion are compared with each other and a data link is reconstructed.

Abstract: In an external storage, an I/O process is continued without any intervention of a user or a host system at failure of a controller. When a failure occurs in a controller, a host system 10 recognizes the failure of the controller. Before the failure is notified to the user and application to stop the job, the substitutive controller reads the SCSI-ID possessed by an SCSI port of the failed controller from a shared memory, registers the SCSI-ID of the SCSI port to the SCSI port associated with the substitutive controller, and erases by a port address resetting facility 45 of the substitutive controller the SCSI-ID possessed by an SCSI port of the failed controller. Thanks to the provision, since the SCSI-ID specified at issuance of an I/O request is transferred between the controllers, the user or the host system need not alter the I/O request issuing route. Moreover, while the host system does not recognize the error, the transfer can be conducted.

Abstract: In an external storage, an I/O process is continued without any intervention of a user or a host system at failure of a controller. When a failure occurs in a controller, a host system 10 recognizes the failure of the controller. Before the failure is notified to the user and application to stop the job, the substitutive controller reads the SCSI-ID possessed by an SCSI port of the failed controller from a shared memory, registers the SCSI-ID of the SCSI port to the SCSI port associated with the substitutive controller, and erases by a port address resetting facility 45 of the substitutive controller the SCSI-ID possessed by an SCSI port of the failed controller. Thanks to the provision, since the SCSI-ID specified at issuance of an I/O request is transferred between the controllers, the user or the host system need not alter the I/O request issuing route. Moreover, while the host system does not recognize the error, the transfer can be conducted.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: N_Port_Name information capable of distinctly identifying a host computer has seen set in a microprocessor 42 of a storage controller 40 prior to start-up of host computers 10, 20, 30; upon startup of the host computers 10, 20, 30, when the storage controller 40 receives a frame issued, then the microprocessor 42 operates to perform comparison for determining whether the N_Port_Name information stored in the frame has been already set in the microprocessor 42 and registered to the N_Port_Name list within a control table maintained. When such comparison results in match, then continue execution of processing based on the frame instruction; if comparison results in failure of match, then reject any request.

Abstract: In an external storage, an I/O process continues without any intervention of a user of a host system upon failure of a controller. When a failure occurs in a controller, a host system recognizes the failure of the controller. Before the failure is notified to the user and application program to stop the job, the substitute controller reads the SCSI-ID possessed by an SCSI port of the failed controller from a shared memory, registers the SCSI-ID of the SCSI port to the SCSI port associated with the substitute controller, and erases by a port address resetting facility of the substitute controller the SCSI-ID possessed by an SCSI port of the failed controller. Due to such provision, since the SCSI-ID specified at issuance of an I/O request is transferred between the controllers, the user or the host system need not alter the I/O request issuing route.

Abstract: A storage array system having a plurality of physical storage devices from and into which data are read and written by a host system, comprising a physical system configuration information table which stores configuration information of the plurality of physical storage devices therein; a logical system configuration information table which stores therein configuration information of a plurality of logical storage subsystems in the case where the plurality of physical storage devices have been divided into the logical storage subsystems; and a division designation device which effects at least one of a number of designations in compliance with a command received from the host system.

Abstract: A vibratory liquid detector which includes a detecting element secured to a free end of a vibration transmission shaft. The detector is suspended in a liquid and receives vibration from the vibration transmission shaft. A spring member supports the vibration transmission shaft and has a fixed end, secured to an intermediate portion of the vibration transmission shaft, and a free end located at a position spaced apart from the periphery of the vibration transmission shaft. The free end is also axially spaced from the fixed end, and includes a support part supporting the whole detecting unit. The spring member provides satisfactory elasticity with respect to torsional vibrations of the vibration transmission shaft between the fixed and the free ends, thus permitting adequate vibrational energy transmission from the vibrator to the detecting element via the vibration transmission shaft.