JP4285202B2 - Compound computer system and compound I / O system - Google Patents

Description

  The present invention provides a system capable of backing up data in a storage device between a host computer and an I / O subsystem that cannot be directly connected due to different access interfaces, and a plurality of I / Os having different access interfaces for the host computer. It relates to the system to which the subsystem is connected.

  In the mainframe, data management functions for the purpose of optimal data placement and efficient operation support for large-scale storage tiers (storage tiers) that combine external storage devices with different processing speeds and storage capacities The integrated storage management function is substantial, for example, corresponds to IBM's DFSMS (Data Facility Storage Management System), and is described in detail in Non-Patent Document 1.

  Through this management function, the disk data of the I / O subsystem of the mainframe can be backed up to a medium such as a magnetic tape or a magnetic tape library that can store data with a low bit cost or a large capacity.

  On the other hand, an open system such as a personal computer or a workstation is not equipped with a medium such as a magnetic tape or a magnetic tape library that can store a large amount of data such as a main frame.

  In general, open systems such as personal computers and workstations access disks according to a fixed-length record format, and mainframes access disks according to a variable-length record format called the count key data format. ing.

  For this reason, the disk subsystem for the main frame and the disk subsystem for the open system are often configured separately.

  On the other hand, Patent Document 1 discloses a technique for transmitting and receiving data between I / O subsystems.

US Pat. No. 5,155,845

IBM System Journal (IBM SYSTEMS JOURNAL), Vol. 28, No1, 1989

  Since the host computers are different, the open system disk subsystem and the mainframe disk subsystem individually operate and manage backups and the like. However, as already mentioned, since there is no medium such as a magnetic tape or a magnetic tape library that can store a large amount of data in an open system, it is effective to take a backup in the I / O subsystem of the mainframe. However, an ordinary open system disk system cannot be directly connected to the main frame because the interface is different.

  On the other hand, Patent Document 1 does not describe how to realize read / write processing for a storage system that is not directly connected to a host computer.

  An object of the present invention is to provide a system for backing up data in a storage device between a host computer and an I / O subsystem that cannot be directly connected due to different access interfaces. In particular, it is to provide a system that backs up data of an I / O subsystem of an open system from a mainframe that is not directly connected to the I / O subsystem.

  Another object of the present invention is to enable access from the main frame to a storage device of an open system I / O subsystem that is not directly connected to the main frame. .

  Still another object of the present invention is to provide a system in which two or more I / O subsystems having different interfaces can be connected to a main frame.

  In order to achieve the above object, the present invention includes a first host computer and one or more external storage devices that are directly connected to the first host computer through a variable-length recording format interface. A first I / O subsystem, a second host computer, and a second fixed length recording format interface connected directly to the second host computer and including one or more external storage devices 2, a composite computer system including a communication mechanism that connects the first I / O subsystem and the second I / O subsystem, and the first I / O subsystem. Includes information indicating the device address of the external storage device, information indicating whether the device address is assigned to the external storage device of the first or second I / O subsystem, and the second I / O subsystem. External memory And a table for storing device addresses in the second I / O subsystem of the external storage device, and the external storage to be read / written from the first host computer. An external storage device address included in the read / write request with reference to the table when a read / write request is received that includes a device address and conforms to the variable length recording format interface If the device address in is not assigned to the external storage device included in the first I / O subsystem, but is assigned to the external storage device included in the second I / O subsystem, Means for determining to send the read / write request according to a variable length recording format interface to the second I / O subsystem; Converting the read / write request according to the variable length recording format interface decided to be sent to the O subsystem into a read / write request according to the fixed length interface, and Means are provided for sending to the second I / O subsystem.

  A first host computer; and a first I / O subsystem directly connected to the first host computer via a variable-length recording format interface and including one or more external storage devices; A backup system connected to the first host computer; a second host computer; and the second host computer directly connected to the first host computer via a fixed-length recording format interface. A composite computer system including a second I / O subsystem including an external storage device and a communication mechanism for connecting the first I / O subsystem and the second I / O subsystem. One host computer includes an address of an external storage device to which data is to be read from the first I / O subsystem and follows the variable length recording format interface. A means for issuing a read request and backing up the data received from the first I / O subsystem to the backup system, wherein the first I / O subsystem is an external storage; The device address of the device, information indicating whether the device address is assigned to the external storage device of the first or second I / O subsystem, and the external storage device of the second I / O subsystem A table for storing device addresses in the second I / O subsystem of the external storage device if assigned, and an external storage device address to be read from the first host computer, and When a read request according to the variable-length recording format interface is received, the external storage device address included in the read request is referred to by referring to the table. If the device address in is not assigned to the external storage device included in the first I / O subsystem, but is assigned to the external storage device included in the second I / O subsystem, Means for deciding to send the read request according to a variable length recording format interface to the second I / O subsystem; and the variable decided to send to the second I / O subsystem. The read request according to the long recording format interface is converted into a read request according to the fixed length interface, and is sent to the second I / O subsystem. Means for sending data received from the system to the first host computer is provided.

  A first host computer; and a first I / O subsystem directly connected to the first host computer via a variable-length recording format interface and including one or more external storage devices; A backup system connected to the first host computer; a second host computer; and the second host computer directly connected to the first host computer via a fixed-length recording format interface. A composite computer system including a second I / O subsystem including an external storage device and a communication mechanism for connecting the first I / O subsystem and the second I / O subsystem. One host computer includes an address of an external storage device to which data is to be written to the first I / O subsystem, and conforms to the variable length recording format interface. A means for issuing a write request and sending data read from the backup system to the first I / O subsystem, wherein the first I / O subsystem is a device address of an external storage device; Information indicating whether the device address is assigned to the external storage device of the first or second I / O subsystem and the external storage device of the second I / O subsystem A table for storing device addresses in the second I / O subsystem of the external storage device, the external storage device address to be written from the first host computer, and the variable length When a write request according to the recording format interface is received, the device address in the external storage device address included in the write request is referred to by referring to the table. The variable length recording is not assigned to the external storage device included in the first I / O subsystem but is assigned to the external storage device included in the second I / O subsystem. Means for determining to send the write request according to a format interface to the second I / O subsystem; and the variable length recording format determined to be sent to the second I / O subsystem. The write request according to the interface is converted into a write request according to the fixed-length interface, sent to the second I / O subsystem, and the data received from the first host computer Is sent to the second I / O subsystem.

  Also, a first I / O subsystem including one or more external storage devices and a second I / O subsystem connected to the first I / O subsystem and including one or more external storage devices The first I / O subsystem includes a device address of an external storage device, and the device address is the first or second I / O. Information indicating to which external storage device of the O subsystem is assigned, and the second I / O sub of the external storage device when assigned to the external storage device of the second I / O subsystem When a table storing device addresses in the system and a read / write request specifying an external storage device address to be read / written from the host computer are received, the table is referred to. The device address in the designated external storage device address is not assigned to the external storage device included in the first I / O subsystem, but is included in the second I / O subsystem. If it is assigned to a device, it has means for sending the read / write request to the second I / O subsystem.

A first I / O subsystem having a variable-length recording format interface and including one or more external storage devices, and a first I / O subsystem having a fixed-length recording format interface and including one or more external storage devices. A composite I / O system connected to a host computer, including two I / O subsystems and a communication mechanism for connecting the first I / O subsystem and the second I / O subsystem The first I / O subsystem includes a device address of the external storage device and information indicating whether the device address is assigned to the external storage device of the first or second I / O subsystem; A table for storing device addresses in the second I / O subsystem of the external storage device when assigned to the external storage device of the second I / O subsystem; When a read / write request including an external storage device address to be read / written is received from the computer and in accordance with the variable length recording format interface, the table is referred to, The device address in the external storage device address included in the read / write request is not assigned to the external storage device included in the first I / O subsystem, and the second I / O subsystem Means for determining that the read / write request in accordance with the variable length recording format interface is to be sent to the second I / O subsystem when assigned to an external storage device included in The read / write request according to the variable length recording format interface decided to be sent to the second I / O subsystem is sent to the fixed length interface. Therefore the re - converted into read / write request, and to have a means for sending to said second I / O subsystem.

  According to the present invention, it is possible to back up data between I / O subsystems having different access interfaces.

  As a result, the data of the open system I / O subsystem can be backed up to the mainframe I / O subsystem.

  In addition, the mainframe backup mechanism includes a high-capacity, high-performance, high-reliability MT library system, so the I / O subsystem data of the open system can be backed up to the high-performance, high-reliability mainframe. The mechanism can be backed up.

  Also, different I / O subsystems can be connected to the mainframe.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing an example of a computer system that is an object of the present invention.

  The processing system A100 includes a main frame 101, a channel interface A102, a channel interface B103, a magnetic tape (MT) control device 106, a magnetic tape library control device 130, a magnetic tape library 107, a disk control device A104, a disk device group A105, and a service processor. 109.

  The main frame 101 accesses the disk controller A104 via a channel interface B103 according to a variable length record format called a count key data format.

  Here, the count key data format is a record format in which a record which is a unit of read / write is composed of three fields called a count part, a key part and a data part. .

  The count section stores a record identifier, the key section stores key information for accessing the record, and the data section stores data used by the application program. The

  Hereinafter, the magnetic tape (MT) control device 106, the magnetic tape library control device 130, and the magnetic tape library 107 are collectively referred to as the MT library system 116.

  The storage hierarchy connected via the channel interface includes not only a magnetic tape but also an optical disk or the like. Hereinafter, an example in which the MT library system 116 is connected will be described.

  The disk control device A 104 includes own control device connection disk information 314 and other control device connection disk information 315.

  The own control device connection disk information 314 and the other control device connection disk information 315 are information provided to enable access to the disk device of the I / O subsystem not directly connected from the main frame. Details of this will be described later.

  The processing system B110 includes an open system host 111, a SCSI interface (Small Computer System Interface) 112, a disk control device B113, a disk device group B114, and a service processor B115.

  The open host 111 accesses the disk controller B 113 via the SCSI interface 112 having a fixed length record as a read / write unit.

  The disk controller A104 and the disk controller B113 are connected by a communication path. The communication path 108 may be, for example, a SCSI cable b117.

  Hereinafter, the count key data format is referred to as a CKD format, and the fixed-length block format is referred to as an FBA (Fixed Block Architecture) format.

  Hereinafter, a CKD record is referred to as a CKD record, and an FBA record is referred to as an FBA record.

  FIG. 2 is a diagram showing another example of a computer system that is an object of the present invention. One main frame I / O subsystem and two or more open system I / O subsystems Is connected.

  In the processing system X120, an interface between the open system host X121 and the disk control device X123 is connected by a Fiber Channel interface 122. The Fiber Channel interface 122 is an optical cable, and can increase the connection distance between the host and the control device.

  However, a Fiber Channel interface based on SCSI is often adopted between the host and the control device.

  Also, the disk controller X123 and the disk controller B113 may be connected by an interface such as the Fiber Channel interface X126.

  The data backup in the configuration of FIG. 2 is an extension of the data backup in the configuration of FIG.

  The basic operation of each device is that the main frame 101 and the open hosts 111 and 121 are connected via the respective interfaces to the magnetic tape library 107, which is an external storage device, or the disk device group A 105, the disk device group B 114, the disk The device group X124 is accessed.

  The process of the mainframe 101 is under the control of an arbitrary operating system that supports the channel interface, for example, VOS3 (Virtual-storage Operating System 3) of Hitachi, and the process of the open host supports the SCSI interface. Stored externally through each interface under the control of any operating system, such as UNIX (UNIX is a registered trademark of X / Open in the United States and other countries) Establish a route to the data.

  FIG. 3 is a diagram showing the configuration of the disk controller A104.

  The disk controller A104 includes an MPU 302 that executes a control system process 307 of this disk controller, a memory device 301, a host data transfer device 303, a disk cache device 304, an I / O intersubsystem data transfer device 305, and a disk transfer device. 306 comprises a bus 308 for connecting these devices.

  The control system process 307 operates in a multitasking or multiprocessor environment.

  The memory device 301 includes various micro programs 312 and various data 313.

  In particular, in the case of the disk control device A104, as described in the description of FIG. 1, the own control device connection disk information 314 and the other control device connection disk information 315 are stored.

  Since the disk controller B113 and the disk controller X123 have the same configuration, they are omitted.

  However, in the case of the disk control device B113 and the disk control device X123, it is not necessary to include the own control device connection disk information 314 and the other control device connection disk information 315.

  The own control device connection disk information 314 indicates the connection relationship of the control devices and the like stored in the memory device 301 of the disk control device A104. The self-control device connection disk information 314 is information existing corresponding to the disk device.

  Self-control device connection disk information 314 is shown in FIG.

  The device address 400 is an identifier for identifying the disk device to be read / written by the host computer such as the main frame 101, and is issued by the host computer such as the main frame 101. This information is also included in the read / write request.

  The own control device connection information 401 is information indicating whether or not the disk device corresponding to the control device connection disk information 314 is actually connected to the control device.

  The other control device connection pointer 402 indicates whether this control device connection disk information 314 is assigned to a disk device connected to another control device.

  If it is assigned, the pointer points to the corresponding other control device connection disk information 315. If not assigned, the pointer is null.

  Therefore, when the other control device connection pointer 402 is valid (when the device address 400 is assigned to a disk device connected to another control device), the own control device connection information 401 is not assigned. It is in.

  When the other control device connection pointer 402 is invalid (when the device address 400 is not assigned to a disk device connected to another control device), the own control device connection information 401 is assigned. It may indicate a state of no.

  That is, the device address 400 may not be assigned to a disk device connected to the own control device, or may not be assigned to a disk device connected to another control device.

  The attribute 403 is device-specific information such as the interface, function, data format type, and block length of the corresponding disk device.

  The other control device connection disk information 315 shown in FIG. 5 is information corresponding to a disk device not directly connected to the disk control device A104.

  The other control device connection disk information 315 is pointed from any one of the own control device connection disk information 314.

  The connection control device address 500 stores the address of the control device to which the disk device corresponding to the other control device connection disk information 315 is connected. In this embodiment, the disk controller B113 is stored.

  A disk address 501 indicates an address assigned to a corresponding disk device in a control device actually connected.

  The own control device connection disk information 314 and the other control device connection disk information 315 are set by the service processor 109, for example.

  In this embodiment, as shown in FIG. 6, the main frame 101 receives a disk from the self-control device connection disk information 314 and the other control device connection disk information 315 shown in FIGS. 4 and 5. It is recognized that the disk device group B114 (disk C, disk D) connected via the control device B113 is also connected to the disk control device A104.

  This is because the disk controller A104 assigns an address of an empty disk device in the disk controller A104 to the disk device of the open I / O subsystem.

  Hereinafter, the processing content of the backup processing will be described with reference to FIG. 1, FIG. 7, and FIG.

  Specifically, in FIG. 1, the data in the disk device group B 114 of the open system of the processing system B is backed up to the MT library system 116 via the disk control device A 104 of the processing system A and the main frame 101.

  Conversely, the data backed up in the MT library system 116 is restored to the disk device group B 114 of the open system of the processing system B via the main frame 101 of the processing system A and the disk controller A104.

The above backup and restore are executed in accordance with an instruction from the mainframe 101. First, data in the disk device group B114 of the open system of the processing system B is transferred to the MT via the disk control device A104 of the processing system A and the mainframe 101. A case of backing up to the library system 116 will be described.

  As already described, the main frame 101 recognizes that the disk device group B 114 (disk C, disk D) is also connected to the disk device A 104.

  Therefore, the operation of the main frame 101 is not particularly described because it simply issues a read request to the disk controller A104 and backs up the received data to the MT library system 116.

  When performing backup to the MT library system 116, the mainframe 101 issues a read request to the disk controller A104. In response to the read request from the main frame 101, the disk controller A104 executes processing according to the flowchart of FIG.

  First, in step 700, the corresponding self-control device connection disk information 314 is found from the address of the disk device specified in the read request.

  In step 701, it is checked whether the designated disk device is connected to the disk controller A104.

  If it is connected to the disk control device A104, in step 702, the corresponding data is read from the disk device.

  If it is not connected to the disk controller A104, it is checked in step 703 whether the specified disk device is connected to another disk controller (disk controller B113). That is, it is checked whether the other control device connection pointer 402 has a null value.

  As a result of the check, if it is null and not connected, an error report is made in step 704.

  The operation particularly related to the present invention is the operation after step 705 executed when the designated disk device is connected to another disk control device (disk control device B113).

  First, as a result of the check, if it is not null and connected, in step 705, based on the value of the other controller connection pointer 402, the other controller connected disk corresponding to the designated disk device. The information 315 is found, and the address of the disk control device (disk control device B113) to which the specified disk device is actually connected based on the found other control device connection disk information 315, the disk connected to the disk control device The address of the disk device in the device group B is acquired.

  Next, in step 706, the address of the data to be read received by the read request is converted into the format of the disk device connected to the disk controller B113.

  In a read / write request from the main frame 101, the address of data to be read / written is normally specified by a cylinder number, a head number, and a record number in accordance with the CKD format.

  Hereinafter, a record address represented by a cylinder number, a head number, and a record number is referred to as CCHHR.

  On the other hand, the disk device connected to the disk controller B113 has an access interface specified by LBA (Logical Block Address) according to the FBA format.

  Accordingly, in step 706, the access address of the read target data is converted from the CKD format to the FBA format.

The conversion formula is, for example,
LBA = (CC * number of heads + HH) * track length + record number * record length.

  In step 707, a request is issued to the disk controller B113 to read data from the area calculated in step 706 of the corresponding disk device.

  Step 708 waits for the requested data from the disk controller B113.

  In step 709, the data received from the disk controller B113 is sent to the main frame 101, and the process is completed.

  Since the disk controller 113B only reads the data requested from the disk controller A104 from the corresponding disk device and sends it to the disk controller A104, no particular processing flow is described.

  Next, a case where the data backed up in the MT library system 116 is restored to the disk device group B 114 of the open system of the processing system B via the disk control device A 104 of the processing system A and the main frame 101 will be described.

  As described above, the main frame 101 recognizes that the disk control device group B 113 (disk C, disk D) is also connected to the disk device A 104.

  Accordingly, the operation of the main frame 101 is not particularly described because it only issues a write request to write data read from the MT library system 116 to the disk controller A104.

  In response to the write request from the main frame 101, the disk controller A104 executes processing according to the flowchart of FIG.

  In the processing flow of FIG. 8, the processing in steps 800 to 801 and steps 803 to 806 is the same as the processing in steps 700 to 701 and steps 703 to 706 in FIG. Step 802 is a normal write process because the request from the main frame 101 is a write request.

  Only the parts different from FIG. 7 will be described below.

  In step 807, a request for writing data in the area calculated in step 807 of the corresponding disk device is issued to the disk controller B113.

  Next, at step 808, write data is received from the main frame 1101 and sent to the disk controller B113.

  Next, in step 809, the disk controller B113 waits for a write request completion report. When a completion report is received, the completion report is sent to the main frame 101 to complete the process.

  Since the control device 113B only reads the data requested from the disk control device A104 from the corresponding disk device and sends it to the disk control device A104, no particular processing flow is described.

  The system for backing up the data in the disk device group B 114 of the open system of the processing system B by the processing system A has been described above. A composite I / O system may be configured in which two I / O subsystems having different interfaces are connected to the mainframe. In this case, three or more I / O subsystems may be connected.

It is a figure which shows an example of the outline | summary of the system of an Example. It is a figure which shows another example of the outline | summary of the system of an Example. It is a figure which shows the structure of a disk control apparatus. It is a figure which shows the structure of self-control apparatus connection disk information. It is a figure which shows the structure of other control apparatus connection disk information. It is a figure which shows the connection relation of the disk apparatus seen from the main frame. It is a figure which shows an example of the processing flow of the disk control apparatus A at the time of backing up the data of an open type I / O subsystem to the MT library system of a mainframe. It is a figure which shows an example of the processing flow of the disk control apparatus A at the time of restoring data from the MT library system of a mainframe to an open type I / O subsystem.

Explanation of symbols

101 Main frame 102, 103, 122 Channel interface 111, 121 Open system host 112 SCSI interface 104, 113, 123 Disk controller 105, 114, 124 Disk device group 106 Magnetic tape controller 107 Magnetic tape library 108 Communication path 109, 115 125 Service processor 116 MT library system 130 Library control device 301 Memory device 302 MPU
303 Host data transfer device 304 Disk cache device 305 I / O inter-subsystem data transfer device 306 Disk transfer device 307 Control system process 312 Microprogram 313 Data 314 Self-control device connection disk information 315 Other control device connection disk information

Claims (3)

A system for storing data,
A first storage device system having a first disk controller connected to the first computer via a first interface and a first disk connected to the first disk controller;
A second storage system having a second disk controller connected to the second computer via a second interface and a second disk connected to the second disk controller;
Connected to the first disk controller via a third interface, connected to the second disk controller via a fourth interface, and a third computer and the third interface type and the fourth interface And a control device for controlling an input / output request from the third computer to the disk.
here,
The format of the first interface and the format of the second interface are the same, the format of the third interface and the format of the fourth interface are the same, and
The first computer accesses the first disk via the first interface and the first disk controller, and the second computer connects the second interface and the second disk controller. Access the second disk via
The control device stores a correspondence relationship between the first disk identification information, the disk controller identification information, and the second disk identification information , receives a request from the third computer, and receives the request. The disk controller connected to the disk indicated by the first disk identification information included in the selected disk controller is selected, and the identification information of the selected disk controller and the disk indicated by the first disk identification information are selected by the selected disk controller. Interface for connecting the request to the selected disk controller using the disk controller identification information and the second disk identification information. Is sent to the selected disk controller,
The selected disk controller uses the transmitted second disk identification information to access a disk of a storage device system to which the selected disk controller belongs. The system of claim 1 , comprising:
The correspondence relationship is set from a service processor connected to the control device. The system of claim 1 , comprising:
The system wherein the first interface and the second interface are SCSI interfaces, and the third interface and the fourth interface are Fiber Channel interfaces.

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