JPH08153030A - File controller and file control system - Google Patents

Abstract

PURPOSE: To avoid that data quantity transferred between centers temporarily exceeds transfer ability between file controllers and a response cannot be made to a file update request from the host by interrupting transfer of update content between the controllers in accordance with the use situation of transmission line between the controllers and storing it only in a storage device. CONSTITUTION: Software A instructs a file controller FCUA to update a file accompanying the update of a remote file. The file controller FCUA updates the remote file and transfers the file to the file controller FCUB. When the update of the file temporarily increases or when the update of the file in software A is delayed owing to the delay of file transfer, remote file transfer is interrupted, and only the writing of an original center-side is executed. The file is accumulated in a volume VOLA, and the file is read out of the volume VOLA when the load of file update is dropped so as to transfer it to an auxiliary center-side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file control device and its control system for storing the equivalent contents of a storage device connected to a computer system on a storage device connected to another computer system.

Occurrence of a disaster such as an earthquake in an area may impair the function of the computer center. In order to prevent this, it is required that a sub-center be installed in a region different from the center (primary center) of a computer system, and that the sub-center take over the function when the primary center fails. In this case, it is necessary to equip the sub center side with a file equivalent to the file of the main center. Such a function is called a remote file, and the present invention relates to a remote file control device and control system.

[0003]

2. Description of the Related Art Conventionally, in order to realize a remote file, file transfer is performed by communication between central processing units (CPUs) of the primary and secondary centers, and file transfer between file control units that control files of the primary and secondary centers. A method of moving a file between the primary and secondary centers by a replaceable medium such as a magnetic tape (MT) has been considered.

At present, there is a file transfer method between the file control devices for the purpose of minimizing the time lag of the file contents of the primary and secondary centers, changing the application program, and minimizing the load increase due to the file transfer of the CPU of the center. Attention has been paid.

The purpose of the remote file is to build an equivalent file at two points. For this reason, it is necessary to have a function of writing equivalent contents to the volumes of the centers that make up the remote file. This way
Even if one of the centers does not function, the latest files can be accessed from the remaining centers.

[0006]

However, the conventional techniques have the following problems. The method of transferring files by CPU communication between the primary and secondary centers increases the load on the CPUs of the primary and secondary centers.
The processing speed of the computer of each center was reduced, and it was necessary to change the application program for writing a file to its own volume or transferring it to another center.

In the remote file control method based on file transfer between file controllers, if the file controller is requested to perform processing that temporarily exceeds the file transfer capability between file controllers, the file transfer will be delayed and the host However, it was not considered to avoid it.

In the method of moving a file using a replaceable medium such as a magnetic tape (MT), since the medium is moved, there is a large time delay until the synchronization of remote files (the time when the files have equivalent contents). Was there.

The present invention solves such a conventional problem, and in the remote file control method by file transfer between file controllers, the amount of data transferred between centers temporarily increases the transfer capability between file controllers. The purpose is to prevent the host from being unable to respond to the file update request from the host and to guarantee the equivalence of volume contents with a time lag.

[0010]

FIG. 1 is a diagram illustrating the principle of the present invention. In FIG. 1, A is a host system (computer system) on the primary center side, B is a host system on the secondary center side, A1 is host software on the primary center side, B1 is host software on the secondary center side, and A2 is a primary center side. A router for line connection, B2 is a router for line connection on the secondary center side, RFILEA is a remote file on the primary center side,
RFILEB is the remote center's remote file, VOL.
A is a volume that is a storage device that stores remote files on the primary center side, and VOLB is a volume that is a storage device that stores remote files on the secondary center side, FCUA
Indicates a file control device (controller) which is a control device for files on the main center side, and FCUB indicates a file control device (controller) which is a control device for files on the sub center side.

In the system configuration of the remote file shown in FIG. 1, the file controller FCUA and FCUB are used to connect the router A to the router A between the primary center and the secondary center, which are located apart from each other.
2, the remote file is transferred via B2, and the remote center file RFILEA of the main center is copied to the remote center file RFILEB of the sub center.

To update the remote file, the host software (hereinafter, referred to as "software") A1 of the host system (hereinafter, referred to as "host") A instructs the file controller FCUA. At this time, this remote file R
Depending on the usage condition of the transmission path, such as when the amount of data of the file transferred to the sub-center side temporarily exceeds the file transfer capability between the file control devices due to the update of FILEA, by the instruction of the host A, or File controller F
The CUA interrupts the file transfer of the updated contents between the file control devices and stores it in the volume VOLA only.

After that, the instruction from the host A or the file control unit FCUA sends the updated contents stored in the volume VOLA to the transmission line between the file control units according to the use status of the transmission line between the file control units. Volume VO
Transfer to LB.

Further, by replacing the roles of the primary and secondary centers with each other, the transmission / reception direction of the update contents is exchanged, and a system for bidirectional transmission / reception in which the primary and secondary centers mutually transfer remote files is configured.

Further, a plurality of control means for controlling remote files are provided in the file control device. Also, a plurality of transmission lines are provided between the file control devices.

Further, a plurality of volumes and a plurality of file control devices are provided. Note that the routers A2 and B2
Is required when data is transferred between the file control units FCUA and FCUB of the primary and secondary centers that are located at a distance from each other through a dedicated line or public line. However, if the transfer distance is short, these routers can be omitted. , The file control devices FCUA and FCUB are directly connected.

[0017]

The operation of the present invention will be described below with reference to FIG. (1) Instruction of remote file (see FIG. 1 (a)) In order to operate the remote file, as a preparation, communication between software A1 and software B1 between host A and host B of the primary and secondary center which is a computer system Defines the relationship of remote files. This is executed by notifying the volume correspondence table (see FIG. 2A). Next, the hosts A and B of each center are shown in the device correspondence table (see FIG. 2).
(See (B)), the file control unit FCU of each center
Notify A and FCUB. After this, the file controller F
The CUA and FCUB can start remote copying of a specified file through communication between file control devices.

As another preparation method, the host A
Sends the device correspondence table (see FIG. 2 (B)) to the file control device FCUA, and then, in the communication between the file control devices,
The device correspondence table can be sent to the file control device FCUB.

(2) File update (see FIG. 1B) With the update of the remote file, the software A instructs the file controller FCUA to update the file.

(3) File Transfer (see FIG. 1C) The file control device FCUA transfers the file to the file control device FCUB, which is the copy destination of the remote file, along with the remote file update.

File controller FC that received the file
The UB writes it to the subordinate volume VOLB according to the definition of the remote file. (4) File reference (see FIG. 1D) When the transfer of the remote file is completed and the writing to the volume VOLB is completed, the volume VO by the host B
By referring to the remote file RFILEB in the LB, data equivalent to the remote file RFILEA in the volume VOLA is obtained.

At this time, if the data amount of the file transferred to the sub-center side temporarily exceeds the file transfer capacity between the file control devices due to the file update of (2), the file control device FCUA is transferred from the host A. Will not be able to answer the file update request. In this case, the delay in the file update of the host A will have an influence on the host A such as a delay in the processing and an increase in the amount of use of the file buffer.

In order to prevent the influence on the host A, when the file update is temporarily increased or when the file update of the host is delayed due to the delay of the file transfer, the remote file transfer is interrupted and only the writing on the main center side is performed. And store this file in the volume VOLA,
When the load of file update is reduced, this file is read from the volume VOLA and transferred to the sub center side.

Further, by providing a plurality of remote file control means in the file control device, when one control means is unusable, it is switched to another control means for processing.

Further, by providing a plurality of transmission lines, volumes, and file control devices, when one transmission line, volume, file control device, etc. cannot be used, they can be switched to different ones for processing. it can.

As described above, it is possible to avoid that the amount of data transferred between the centers temporarily exceeds the transfer capability between the file control devices and cannot respond to the file update request from the host.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. 2 to 9 are views showing an embodiment of the present invention,
2 to 9, the same parts as those in FIG. 1 are designated by the same reference numerals.

(1) Description of Remote File Correspondence Table FIG. 2 is an explanatory diagram of the remote file correspondence table.
2A shows a volume correspondence table, and FIG. 2B shows a device correspondence table. 2A, for example, No. 01,
Volume name LOGVL1 of host A, machine number (number defined on the file control unit FCU side) 301, and host B
Indicates that the volume name VOL001 and the machine number 501 are equivalent.

In FIG. 2B, for example, No. This indicates that the primary center side machine number 301 of 01 and the sub center side machine number 501 are equivalent. In order to operate the remote file, as a preliminary preparation, the volume correspondence table shown in FIG. 2 (A) is passed by software communication between the primary and secondary centers, and the host of each center uses the device correspondence table of FIG. 2 (B). , The file control device of each center is notified.

As another method of advance preparation, the device correspondence table of FIG.
It is also possible to send it to the UA and then send the device correspondence table to the file control device FCUB by communication between the file control devices.

(2) Data flow at the time of remote file transfer (see FIG. 3) FIG. 3 is an explanatory diagram of remote file transfer. Writing a remote file to the copy source volume VOLA is the same as a normal input / output (IO) process.

When the file controller FCUA which has received the write command from the host A determines that it is a write to the volume that constitutes the remote file, it simultaneously writes the write data to the designated volume VOLA Volume file control unit FCU
Data is transferred to B through the router A2, a transmission line such as a communication line, and the router B2.

The file control unit FCUB of the copy destination receives the data received through the transmission path from the designated volume V.
Write to OLB. (3) Data flow when updating only the main center side file (see FIG. 4) FIG. 4 is an explanatory diagram of updating only the main center side file.

As shown in FIG. 3, when the remote file is being updated while the remote file is being transferred between the primary and secondary centers, the amount of data to be transferred may temporarily exceed the transfer capability between the file control units. When it occurs, the remote file transfer is interrupted and the process is switched to the process of updating only the main center side file.

This switching of processing is performed by an instruction from the host A or by the file control unit FCUA monitoring the status of file transfer and detecting that the transfer capacity has been exceeded.

(4) Data flow when transferring files between centers (see FIG. 5) FIG. 5 is an explanatory diagram of file transfer between centers. When the load of the file update request from the host decreases and remote file transfer becomes possible due to the transfer capability between the file control devices, the file control device FCUA sets the volume VOL.
The file RFILEA to be transferred is read from A to the file control unit FCUB, router A2, transmission line, router B
Transfer through 2.

File controller F that received this data
The CUB stores it in the corresponding volume VOLB. By this data transfer, the contents of the remote file RFILEA and the remote file RFILEB of the primary and secondary centers become equivalent.

If the host A notifies the host B that the contents of this file have become equivalent, the host B can refer to the remote file RFILEB as a file equivalent to the remote file RFILEA on the main center side.

This center-to-center file transfer is started by an instruction from the host A or the file control unit FCUA monitoring the status of file transfer and detecting that transfer is possible.

(5) Description by Flowchart FIG. 6 is a flowchart for continuation / interruption processing of remote file transfer. Hereinafter, this process will be referred to as process numbers S1 to S4.
Follow the instructions below.

S1: The host issues an instruction to update the remote file to the file control device, and this processing is started. At this time, the host or the file control device determines the usage status of the transmission line by determining whether the amount of data transferred on the transmission line temporarily exceeds the transfer capability between the file control devices, and the process proceeds to step S2. Move.

S2: The host or the file control device judges whether the amount of data transferred on the transmission line does not temporarily exceed the transfer capability between the file control devices and remote file transfer is possible. If it is determined that remote file transfer is possible (YES), the process proceeds to step S3. If this file transfer is not possible (NO), the process proceeds to step S4.

S3: The file control device continues the transfer of the remote file between the file control devices and ends this processing. S4: If the amount of data transferred on the transmission path temporarily exceeds the transfer capability between the file control devices and the remote file transfer is impossible in the judgment of the processing S2 (N
O), an instruction from the host or the file control device interrupts the remote file transfer between the file control devices, and this processing ends. In this case, only the main center side file is updated.

FIG. 7 is a flow chart of file transfer processing between centers. Hereinafter, this process will be referred to as process numbers S11 to S.
13 will be described. S11: When the remote file transfer is interrupted in the process S4 of FIG. 6, an instruction from the host or the file control device
The load of the file update request from the host is reduced, and it is determined whether or not the transfer between the file control devices is possible, and the usage status of the transmission path is determined.

S12: The host or file control device
It is judged whether the load of the file update request from the host is reduced and the remote file transfer between the file control devices is possible. If the remote file transfer is possible by this determination (YES), the process proceeds to step S13, and if the file transfer is not possible (NO), this process ends.

S13: The remote file transfer between the centers is started, and this processing ends. (6) Description of a case where a plurality of transmission lines are provided FIG. 8 is an explanatory diagram of a case where a plurality of transmission lines are provided.
In FIG. 8, two routers A21 and A22, two transmission lines, and two routers B21 and B22 are provided between the file control device FCUA and the file control device FCUB.

For example, when the route of the router A21, the transmission line, and the router B21 is unusable due to a failure or the like, the process can be performed by switching to the route of the router A22, the transmission line, and the router B22.

As described above, a plurality of transmission lines are provided between the file control devices, and when a certain transmission line is unusable, it can be switched to another transmission line to perform processing. You can gain credibility.

(7) Description of a case where a plurality of volumes and a file control device are provided FIG. 9 is an explanatory view of a case where a plurality of volumes and a file control device are provided. In FIG. 9, two volumes A and A'and a file controller FC are provided on the main center side.
UA and FCUA 'are provided.

For example, if the volume A or the file control unit FCUA becomes unusable for some reason while the volume A and the file control unit FCUA are in use, another volume A'and the file control unit FCUA 'are switched to perform the processing. It can be done and even more system reliability can be obtained.

In the above embodiment, the case where only one control means for executing the remote file is included in the file control device has been shown, but a plurality of this control means can be included in the file control device. . Thereby, when a certain control means is unusable, it can be switched to another means for processing. For example, two interface modules (not shown) in the file control device FCUA for transmitting to the router A2 are provided, and when one is unavailable, the other is switched to the other for processing.

In this way, further system reliability can be obtained. When a plurality of means for executing a remote file are included, in addition to the above-described embodiment, not only two primary and secondary centers but also a plurality of files (three or more) between the centers should be copied. Will also be possible. This also helps improve the reliability of the system.

Further, in the above-mentioned embodiments, the file transfer direction is only one direction, but it is also possible to switch the transfer direction or simultaneously transfer in both directions. As a result, the equivalent update content can be stored in each volume connected to two or more computer systems.

[0054]

As described above, the present invention has the following effects. In the remote file control method by file transfer between file controllers, it is possible to avoid that the amount of data to be transferred temporarily exceeds the transfer capacity between file controllers and cannot respond to the file update request from the host. It is possible to guarantee the equivalence of the contents of a certain volume.

Further, the file control device interrupts the transfer between the file control devices or performs the transfer between the file control devices according to the use status of the transmission path between the file control devices. The processing load can be reduced.

Furthermore, by exchanging the transmission / reception direction of the update contents and bidirectional transmission / reception, it is possible to store the equivalent update contents in each volume connected to two or more computer systems.

Further, by providing a plurality of control means for controlling the remote file in the file control device,
The reliability of the system can be improved. Furthermore, by providing a plurality of volumes and file controllers connected to the transmission path between the file controllers or the host,
The reliability of the system can be further improved.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is an explanatory diagram of a remote file correspondence table according to the embodiment.

FIG. 3 is an explanatory diagram of remote file transfer in an embodiment.

FIG. 4 is an explanatory diagram of updating only a file on the main center side in the embodiment.

FIG. 5 is an explanatory diagram of file transfer between centers in the embodiment.

FIG. 6 Continuation of remote file transfer in the embodiment
It is an interruption processing flowchart.

FIG. 7 is a flowchart of a file transfer process between centers in the embodiment.

FIG. 8 is an explanatory diagram of a case where a plurality of transmission lines are provided in the embodiment.

FIG. 9 is an explanatory diagram when a plurality of volumes and a file control device are provided in the embodiment.

[Explanation of symbols]

 A, B Host system (computer system) A1, B1 Host software A2, B2 Router RFILEA, RFILEB Remote file VOLA, VOLB volume (storage device) FCUA, FCUB File control device (control device)

Claims (17)

[Claims] 1. A computer system, a control device connected to the computer system, and a storage device controlled by the control device. One equivalent content of the storage device connected to the computer system is provided. In order to store in the storage device connected to the other computer system described above, the control device that receives the instruction to update the content of the storage device from this computer system stores the update content in the storage device connected to the control device. In parallel with the processing, when sending the equivalent contents to a control device that controls a storage device connected to one or more other computer systems that should store the equivalent contents via a transmission line connecting the control devices, It is characterized in that the transfer of update contents between control devices is interrupted according to the usage status of the transmission path between the devices, and is stored only in the storage device connected to the computer system. File control device. 2. The update content stored in the storage device is transferred to another control device connected to the control device according to the usage status of the transmission path between the control devices. File controller described. 3. A file control system in which a storage device connected to a computer system and the equivalent contents of this storage device are also stored in a storage device connected to one or more other computer systems. In the case of updating the contents in the storage device connected to the system, the control device controlling the storage device performs one operation in parallel with the process of storing the updated contents in the storage device connected to the control device. When sending the update contents to the control device that controls the storage device connected to the other computer system described above through the transmission path connecting the control devices, the instructions of the computer system are sent according to the usage status of the transmission path. A file characterized in that the transfer of the update contents between the control devices is interrupted, and the update contents are stored only in the storage device connected to the computer system. Control system. 4. The computer system instructs transfer of the update contents stored in the storage device to another control device connected to the control device of the storage device, in accordance with the usage status of the transmission path between the control devices. 4. The file control system according to claim 3, wherein the equivalent update content is stored in a storage device connected to another computer system. 5. The control device connected to the computer system transfers the update contents stored in the storage device to another control device connected to the control device according to the usage status of the transmission path between the control devices. 4. The file control system according to claim 3, wherein the equivalent update content is stored in a storage device connected to another computer system. 6. A storage system connected to a computer system, and a file control system for storing the equivalent contents of this storage system also in a storage device connected to one or more other computer systems. When updating the contents of the storage device connected to the system, the control device controlling the storage device performs one or more operations in parallel with the process of storing the updated contents in the storage device connected to the control device. When the update contents are sent to the control device that controls the storage device connected to another computer system through the transmission path connecting the control devices, the control device updates the update information according to the usage status of the transmission path. A file control system characterized in that transfer of contents between control devices is interrupted, and the updated contents are stored only in a storage device connected to the computer system. 7. The computer system instructs the transfer of the update contents stored in the storage device to another control device connected to the control device of the storage device, according to the usage status of the transmission path between the control devices. The file control system according to claim 6, wherein the equivalent update content is stored in a storage device connected to another computer system. 8. A control device connected to a computer system transfers updated contents stored in a storage device to another control device connected to the control device according to the usage status of a transmission path between the control devices. 7. The file control system according to claim 6, wherein the equivalent update content is stored in a storage device connected to another computer system. 9. A file control system in which a storage device connected to a computer system and the equivalent contents of the storage device are also stored in a storage device connected to one or more other computer systems. In the case of updating the contents of the storage device connected to the storage device, the control device controlling the storage device, in parallel with the process of storing the updated contents in the storage device connected to the control device, executes one or more other When sending the update contents to the control device controlling the storage device connected to the computer system through the transmission path connecting the control devices by exchanging the transmission / reception direction between the storage devices and transmitting / receiving in both directions. In addition, depending on the usage status of the transmission path, the transfer of the update contents between the control devices is interrupted by the instruction of the computer system, and only the storage device connected to the computer system is interrupted. A file control system for storing the updated contents. 10. The computer system instructs the transfer of the update contents stored in the storage device to another control device connected to the control device of the storage device, according to the usage status of the transmission path between the control devices. 10. The file control system according to claim 9, wherein the equivalent update content is stored in a storage device connected to another computer system. 11. A control device connected to a computer system sends updated contents stored in a storage device to another control device connected to the control device according to the usage status of a transmission path between the control devices. 10. The file control system according to claim 9, wherein the equivalent update content is stored in a storage device connected to another computer system by transferring. 12. A file control system in which a storage device connected to a computer system and the equivalent contents of the storage device are also stored in a storage device connected to one or more other computer systems. In the case of updating the contents of the storage device connected to the storage device, the control device controlling the storage device, in parallel with the process of storing the updated contents in the storage device connected to the control device, executes one or more other When sending the update contents to the control device controlling the storage device connected to the computer system through the transmission path connecting the control devices by exchanging the transmission / reception direction between the storage devices and transmitting / receiving in both directions. In addition, the control device connected to the computer system interrupts the transfer of the update contents between the control devices according to the usage status of the transmission line, and the storage device connected to the computer system. A file control system characterized in that only the device stores the updated contents. 13. The computer system instructs the transfer of the update contents stored in the storage device to another control device connected to the control device of the storage device, according to the usage status of the transmission path between the control devices. 13. The file control system according to claim 12, wherein the equivalent update content is stored in a storage device connected to another computer system. 14. A control device connected to a computer system transfers updated contents stored in a storage device to another control device connected to the control device according to the usage status of a transmission path between the control devices. 13. The file control system according to claim 12, wherein the equivalent update content is stored in a storage device connected to another computer system by doing so. 15. A file control system in which a storage device connected to a computer system and the equivalent contents of the storage device are also stored in a storage device connected to one or more other computer systems. When updating the contents of a storage device connected to the storage device, one or more other computer systems are installed in parallel with the process of storing the updated contents in the storage device of the control device in the control device that controls the storage device. When the update contents are transferred to the control device controlling the storage device connected to the control device via the transmission line connecting the control devices, the update contents are transferred between the control devices according to the usage status of the transmission line. The update contents are stored only in the storage device connected to the computer system after interruption, and then the update contents stored in the storage device are stored in the storage device according to the usage status of the transmission path. File control system includes a plurality of control means, certain control means when unavailable, was characterized by conducting processing by switching to a different controller for transfer control device connected to another control device for. 16. A file control system in which a storage device connected to a computer system and the equivalent contents of the storage device are also stored in a storage device connected to one or more other computer systems. When updating the contents of a storage device connected to a storage device, the control device that controls the storage device stores the updated contents in the storage device of the control device in parallel with one or more other computer systems. When transferring the update contents to the control device controlling the connected storage device via the transmission path connecting the control devices, the transfer of the update contents between the control devices is interrupted depending on the usage status of the transmission path. Then, the update contents are stored only in the storage device connected to the computer system, and thereafter, the update contents stored in the storage device are stored in the storage device according to the usage status of the transmission path. The transfer is performed to another control device connected to the control device, and a plurality of transmission lines between the control devices are provided, and when one transmission line is unusable, it is possible to switch to another transmission line for processing. Characterized file control system. 17. A computer in a file control system, wherein a storage device connected to a computer system and the equivalent contents of the storage device are also stored in a storage device connected to one or more other computer systems. When updating the contents of the storage device connected to the system, the control device controlling the storage device stores the updated contents in the storage device of the control device in parallel with one or more other computer systems. When the update contents are transferred to the control device controlling the storage device connected to the control device via the transmission line connecting the control devices, the update contents are transferred between the control devices according to the usage status of the transmission line. The update contents are stored only in the storage device connected to the computer system, and then the update contents stored in the storage device are stored according to the usage status of the transmission path. So as to transfer to another control device connected to the control unit of the location, the storage device and a control device of the certain computer system,
A file control system which is provided with a plurality of storage devices, respectively, and when a certain storage device or its control device becomes unusable, it is switched to another storage device and its control device for processing.