JPH11305949A - Remote transfer method for file controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a remote direct access storage device(DASD) function for writing data from a regular center side host only to a sub center side volume while using a remote file control unit(FCU) in a current state. SOLUTION: The machine number of a virtual volume to be virtually handled as a volume, which does not really exists but exists under the control of an FCU 10A, is previously defined inside the FCU 10A on the regular center 1A side and when the FCU 10A on the regular center 1A side receives a write command designating the machine number of the virtual volume from a host 2A on the regular center 1A side, data to be written by the write command are transferred through a communication line 6 to an FCU 10B on the sub center 1B side without being written in the volume on the side of the regular center 1A, and written through the FCU 10B on the sub center 1B side into a volume 4B really existent under the control of that FCU 10B.

Description

DETAILED DESCRIPTION OF THE INVENTION

(Contents) Technical field to which the invention pertains Prior art (FIGS. 3 to 8) Problems to be Solved by the Invention Means for Solving the Problems Embodiments of the Invention (FIGS. 1 and 2) Effects of the Invention

[0002]

BACKGROUND OF THE INVENTION Generally, a sub-center (backup system) is installed at a location (remote location) different from the installation location of a main center (business system) for performing essential business, and the work of the main center is performed by the sub-center. In a system configured to be able to back up, a file control device having a remote transfer function [hereinafter referred to as a remote FCU (File C
ontrol Unit)].

According to the present invention, a remote DASD (Direct Access Strategies) is used to transfer and write data from a host computer on the primary center side only to a volume (magnetic disk device) on the secondary center side using the remote FCU described above.
orage Device) remote transfer method to realize the function.

[0004]

2. Description of the Related Art In recent years, in the case where the operation of a main center (business system) for performing essential business is stopped due to a disaster such as an earthquake or a sudden failure, as shown in FIG. It is common to install a sub-center (backup system) 1B at a remote location different from the above.

[0005] As described above, the remote center 1B in the remote place
With reference to FIG. 3, a description will be given of the configuration of a system that allows backup of the business of the main center 1A.
In FIG. 3, the components that perform the same function in the main center 1 </ b> A and the sub center 1 </ b> B are denoted by the same reference numerals, and the reference numerals indicating the components belonging to the main center 1 </ b> A are denoted by “A”. In addition, the reference numerals indicating the components belonging to the sub-center 1B are denoted by “B”.

The main center 1A is connected to a host computer (C
PU; hereinafter abbreviated as host) 2A, file control unit [hereinafter referred to as FCU (File Control Unit)] 3A,
Volume (magnetic disk device) 4A and adapter 5
A. The host 2A performs processing for the original business, and is connected to the communication line 6 via the adapter 5A. FCU 3A is host 2A
It is interposed between the host and the volume 4A, and performs write / read control on the volume 4A in accordance with an input / output signal (hereinafter sometimes simply referred to as I / O) from the host 2A.

[0007] Similarly to the main center 1A, the sub center 1B also has a host computer (CPU; hereinafter abbreviated as host) 2
B, FCU 3B, volume 4B, and adapter 5B. The host 2B takes over the business process from the main center 1A during backup and is connected to the communication line 6 via the adapter 5B. The FCU 3B is interposed between the host 2B and the volume 4B, and performs write / read control on the volume 4B according to input / output signals from the host 2B.

When the data of the volume 4A is changed in the main center 1A with the execution of the business, information on the changed data is sent to the communication line 6 through the host 2A and the adapter 5A. It is transmitted to the sub center 1B via the communication line 6. The information is received by the host 2B from the communication line 6 through the adapter 5B in the sub center 1B.
Outputs I / O to FCU3B,
The same change as the data of the volume 4A of the main center 1A is performed on the data of the volume 4B. Thus, the same data is always held in the volume 4A of the primary center 1A and the volume 4B of the secondary center 1B. That is, the volume 4B of the sub center 1B is always constructed to be equivalent to the volume 4A of the main center 1A.

Therefore, if the operation of the main center 1A stops due to a disaster such as an earthquake or a sudden failure, a volume 4B equivalent to the volume 4A of the main center 1A is constructed in the sub center 1B. So, Deputy Center 1
B immediately takes over the operation of the main center 1A,
The business by the main center 1A can be backed up.

However, since the host 2A performs processing for the original business and has a heavy load from the beginning, when the host 2A of the primary center 1A transfers data to the secondary center 1B as described above, too large data is required. Could not be transferred and efficient transfer could not be performed. Therefore, in each of the main center 1A and the sub center 1B, instead of the FCUs 3A and 3B shown in FIG. 3, as shown in FIG. 4, FCUs 10A and 10B having a remote transfer function (hereinafter, referred to as remote FCUs) are provided. Communication line 6 between the remote FCUs 10A and 10B
Has been proposed and used. In this system, the data transfer (remote transfer) from the primary center 1A to the secondary center 1B is performed by the remote FCU 10A, so that the load on the host 2A is distributed,
Data transfer can be performed efficiently.

As the communication line 6 connecting the remote FCUs 10A and 10B, for example, a high-speed digital line or an ATM line is used. In addition, host 2
A, 2B and the remote FCUs 10A, 10B are connected by a channel interface,
P between the CUs 10A and 10B and the volumes 4A and 4B
CI (Peripheral Component Interconnect) interface or SCSI (Small Computer System Interface)
ce) Connected by interface.

The configuration of the remote FCUs 10A and 10B will be described with reference to FIG. As shown in FIG.
Each of the remote FCUs 10A and 10B has a CA (Cha
nnelAdapter) 11, RM (Resource Manager) 12, S
A (Service Adapter) 13, RA (Remort Adapter) 1
4, CFE (Cache Function Engine) 15, SS (Share
d Storage) 16, DA (Device Adapter) 17, and C-
A BUS (Control-BUS) 18 is provided.

The CA 11 is a functional unit (module) responsible for interface control (connection control) with the hosts 2A and 2B, which are higher-level devices. The RM 12 is a functional unit for controlling internal resources, and is a control table. (Hereinafter, referred to as TS (Table Storage)) 12a. Further, the SA 13 is a remote FCU 10
A is a function unit that is in charge of maintenance of A and 10B.
Is connected to the other remote FCU (10
B or 10A), and the CFE 15 is a functional unit in charge of managing (controlling) the cache memory in the SS 16, and has a memory (hereinafter, referred to as TS) 13a that forms a control table. I have.

The DA 17 is a functional unit that is responsible for interface control (connection control) with the lower-level devices (magnetic disk devices) 4A and 4B, and is a C-BUS.
Reference numeral 18 denotes a route through which the above-described functional units (reference numerals 11 to 17) communicate with each other, and is used for transmitting and receiving control information between the functional units. Here, the shared memory unit including the cache memory and the like is collectively referred to as SS (reference numeral 16). Each functional unit (reference numerals 11 to 17) is an MPU (Micro Processing Uniform).
t), and operates by incorporating microprogram code. Furthermore, one remote FCU
10A (or 10B) multiple (eg up to 8)
RA14 can be mounted, and a plurality of (for example, up to eight) communication lines 6 can be laid between the main center 1A and the subcenter 1B. 6 and 7
In the example shown in (1), four RAs 14 are mounted on each of the remote FCUs 10A and 10B, and four communication lines 6 are laid.

As described above, the RA 14 in the remote FCU 10A is connected to the RA 14 in the remote FCU 10B in the remote sub-center 1B via the communication line 6, and as shown by the arrow in FIG. Remote FCU that received data from CA2A by CA11
10A writes the data from the DA 17 to the volume 4A connected to it,
From the remote FCU 10B via the communication line 6
A14 is transferred as backup data. Such data transfer is called “remote transfer”. Similarly to the remote FCU 10A, the remote FCU 10B of the sub-center 1B that has received the data by the remote transfer writes the data from the DA 17 to the volume 4B connected under it. In FIG. 6, the data transfer path is shown as a shaded area.

Next, the operation of the entire system (host 2A and remote FCUs 10A and 10B) shown in FIG. 4 will be described with reference to FIG. In the main center 1A, the host 2A (software) uses the RA 14 and the sub center 1B on the main center 1A side.
The corresponding relationship with the RA 14 on the side and the corresponding relationship between the volume 4A on the main center 1A side and the volume 4B on the sub center 1B side are set as a table inside the remote FCU 10A.

The host 2A of the main center 1A specifies the set volume number of the main center 1A and issues a remote transfer designation write command to the remote FCU 10A of the main center 1A (arrow A1). reference).
The command issued from the host 2A in the main center 1A is, for example, DX (Define Extent), LR (Locat
e Record), C consisting of WCKD (Write Count, Key, Data)
It is a CW (Channel Command Word) chain. And
When the host 2A of the primary center 1A performs a write process involving data backup (that is, remote transfer), a write command for the remote shadow volume (a backup write command to the volume 4B of the secondary center 1B)
Is activated from the host 2A to the CA of the remote FCU 10A.
11 is performed by DX of CCW.

Main center 1A that receives the write command
The remote FCU 10A on the side stores the data in the cache area (TRK1 to TRK4) secured in the SS 16 therein (see arrow A1), and then the remote FCU 10A on the main center 1A side.
Volume under CU10A (volume of designated machine number)
Write data to 4A (see arrow A2). In parallel with the above items, the remote FCU 10A on the primary center 1A refers to the RA correspondence table and the volume correspondence table in the main center 1A, and from the RA 14, the remote FCU 10B (RA 14) on the sub center 1B side.
(See arrows A3 and A4).

On the side of the sub-center 1B, the remote FCU 10B, which has received the data by the RA 14, temporarily stores the data in a predetermined cache area (TRK1 to TRK1) in the SS 16.
TRK4) (see arrow A5), and refers to the volume correspondence table to write data from SS16 to the specified volume (see arrow A6). After the writing is completed, the remote FCU 10B
A write completion (normal end) notification is sent to U10A.

On the main center 1A side, the remote FCU 10A receiving the completion notification by the RA 14 notifies the host 2A on the main center 1A of the processing end (normal end) through the CA 11, and performs a series of writing processing. finish. As described above, the remote FCUs 10A and 10B
Remote transfer from the main center 1A to the sub-center 1B for one I / O (one set of CCW chains) is performed, and by performing such a remote transfer, the host 2A in the main center 1A controls the volume 4A. Even if changes such as writing are made, equivalent volumes 4A and 4B are always constructed in the primary center 1A and the secondary center 1B.

Next, the conventional remote MT (Magnet
ic Tape) will be described with reference to FIG. In FIG. 8, the same reference numerals as those described above indicate the same or similar portions, and thus description thereof will be omitted. As shown by an arrow in FIG. 8, the host 2A reads data read from the volume 4A to the RAM 3a in the FCU 3A via the DA 17 on the primary center 1A side, as indicated by an arrow in FIG. The data is transferred to the center 1B and written to the magnetic tape device (MT) 22B of the sub-center 1B, thereby backing up the data of the main center 1A.

For this reason, in a system for realizing a remote MT, as shown in FIG. 8, dedicated converters 20A and 20B are provided in a main center 1A and a sub center 1B.
And each of these dedicated converters 20A
And 20B are connected by a communication line 6 such as a high-speed digital line or an ATM line. The dedicated converter 20A in the main center 1A sends out data sent from the host 2A through the channel to the communication line 6, and the dedicated converter 20B in the sub center 1B is sent from the main center 1A through the communication line 6. The received data is sent to a magnetic tape controller (MTC: Magnetic Tape Controller) 21B in the sub center 1B.

The MTC 21B controls data writing to the MT 22B and data reading from the MT 22B.
a, a RAM 21b and an FMT (Fomatter) 21c. The HIC 21a is a functional unit that is connected to the dedicated converter 20B and is in charge of channel interface control (connection control) with the dedicated converter 20B. The RAM 21b stores data from the main center 1A to M
This is for temporarily storing data to be written to T22B and data read from MT22B. F
The MT 21c is a functional unit in charge of interface control (connection control) with the MT 22B.

[0024]

In recent years, as a system succeeding the above-mentioned remote MT, a sub-center 1 has been proposed.
The backup on the B side is performed using a magnetic disk instead of a magnetic tape.
rage Device). At first, the MTC 21B on the side of the sub-center 1B shown in FIG.
It was supposed to be realized by replacing and supporting.

However, the remote D
When constructing an ASD, there are the following problems. (1-1) I / O to DASD is I / O to MT
Because it is more complicated than I / O, the software for remote MT cannot be used as it is for the remote DASD, and the software must be greatly modified.

(1-2) The dedicated converter 20B existing between the host 2A on the main center 1A side and the MTC 21A on the sub center 1B cannot support the complex I / O of DASD, and the dedicated converter 20B It also requires extensive remodeling. Therefore, the remote DAS relayed by the remote FCUs 10A and 10B shown in FIGS.
Although the D method is also conceivable, the original remote FCU 10A,
Considering the function of 10B, there are the following problems.

(2-1) Remote FCUs 10A and 10B
Has the function of writing data to be written to the volume of the main center 1A also to the volume of the sub center 1B, and has the function of writing only to the volume (magnetic disk) of the sub center 1B like a remote DASD. Not. (2-2) In the main center 1A, the I / O (write command) issued by the host 2A must be transmitted to the remote FCU.
A volume machine number that exists under 10A must be specified. Accordingly, if the host 2A issues an I / O designating a device number that does not exist in the main center 1A because data does not need to be written to the volume in the main center 1A, an error occurs. That is,
With the current remote FCUs 10A and 10B, the function of writing data only to the volume on the sub-center 1B side cannot be realized.

The present invention has been made in view of such a problem, and uses a current file controller (remote FCU) with a remote transfer function to transfer data from a main center host to only a sub center volume. It is an object of the present invention to provide a remote transfer method by a file control device, which can realize a remote DASD function for writing a file.

[0029]

In order to achieve the above object, a remote transfer method by a file control device according to the present invention (claim 1) is directed to a file with a remote transfer function which operates in accordance with a command from a host on a main center side. A control device is provided, and on the sub-center side,
In the system in which the file control device on the sub-center side is connected to the file control device on the main center side via a communication line so that data from the file control device on the main center side can be written to the volume, Inside the file control device, the machine number of a virtual volume that is not actually present but is virtually handled as being under the main center file control device is defined in advance,
When the main center file control device receives a write command specifying the virtual volume machine number from the main center host, the data to be written by the write command is transmitted to the communication line without writing to the main center volume. The data is transferred to the sub-center-side file control device via the sub-center-side file control device, and is written by the sub-center-side file control device to a volume existing under the sub-center-side file control device.

In the above-described remote transfer method according to the present invention (claim 1), only the machine number of the virtual volume is valid in the main center file control device, and the main host on the main center side transmits the virtual volume number to the main center file control device. When a write command for designating the volume number is issued, the write data according to the write command is relayed by the main center file controller between the main center host and the sub center file controller. And the data is written to a volume existing on the sub-center side.

That is, in the remote transfer method of the present invention,
In addition to suppressing data writing to the main center side volume, the software (primary center side host) makes it appear that a virtual machine number (virtual volume) that does not actually exist under the main center side file control device exists virtually. Issue a write command by designating the virtual machine number. As a result, a remote DASD function of writing data from the main center host to only the sub center volume can be realized using the current file control device with a remote transfer function as it is.

In the primary center file control device, when a write command designating a virtual volume machine number is received from the primary center host, an area of the nonvolatile memory for data to be written by the write command is received. , A dedicated cache area for storing the data may be secured (claim 2). That is, since it is not necessary to store the write data by the write command in the main center file control device for a long time, only the dedicated cache area is secured and the area of the nonvolatile memory is not secured. In addition, unnecessary overhead can be reduced.

When the transfer of the data to the sub-center file control device is completed in the main center file control device, the dedicated cache area storing the data may be immediately released. Claim 3).
In other words, after the data transfer to the secondary center file control device is completed, there is no need to keep the data inside the primary center file control device. The area can be used effectively.

[0034]

Embodiments of the present invention will be described below with reference to the drawings. A system to which a remote transfer method by a file control device according to an embodiment of the present invention is applied is configured, for example, as shown in FIG. In FIG. 1, the same reference numerals as those described above denote the same or similar parts, and a detailed description thereof will be omitted. Further, the file control device with a remote transfer function according to the present embodiment, that is, the remote FCUs 10A and 10B
Is also configured in the same manner as that shown in FIG. 5, and a detailed description thereof will be omitted.

In the present embodiment, however, as shown in FIG. 1, a real volume 4A is provided on the primary center 1A side, and access (read / write) to the real volume 4A is performed by remote transfer from the host 2A. This is performed via a normal FCU 3A having no function (see FIG. 3). The real volume 4A stores a database and the like used for various processes (business) in the main center 1A.

In this embodiment, the host 2A on the primary center 1A is connected to the remote FCU 10 on the secondary center 1B side.
B and the real volume 4B as remote DASD, the remote FCU 10A on the primary center 1A side
Relaying remote transfer. At this time, although the real volume does not exist under the remote FCU 10A, the device number of the remote DASD virtual volume (hereinafter, referred to as a virtual volume) virtually treated as existing under the remote FCU 10A is FCU
Predefined inside 10A. That is, remote F
The CU 10A executes the IPL (Initial Program Load) after the definition.
ing), it is recognized that the virtual volume is a volume that is valid only for the device number and does not exist.

After the system is started, the host (software) 2A of the main center 1A communicates with the RA 14 of the remote FCU 10A of the main center 1A and the RA 14 of the remote FCU 10B of the sub center 1B, and the main center. 1A side volume and sub center 1
The correspondence with the volume 4B on the B side is
Set as a table inside 10A. When setting the volume correspondence, the above-mentioned virtual volume is designated as the volume on the main center 1A side.

Further, the host 2A on the primary center 1A side
When using the remote DASD function realized by the present embodiment, specify the machine number of the virtual volume,
A write command (write command) for designating remote transfer is issued to the remote FCU 10A. The remote FCU 10A that has received the write command from the host 2A temporarily stores the write data to be written by the write command in the cache area secured in the internal SS 16 (see FIG. 5). Thereafter, the remote FCU 10A transfers the data stored in the cache area to the remote FCU 10B on the sub center 1B side via the communication line 6 without writing the data on the volume on the main center 1A side.
The operation is performed such that the data is written to the real volume 4B that actually exists under the subordinate by 0B. Here, the data transferred to the sub-center 1B includes data read from the real volume 4A through the FCU 3A, a difference log associated with updating data in the real volume 4A, and the like.

On the other hand, the remote FCU 10B of the sub center 1B receiving the data writes the data to the designated volume 4B, and the remote FCU 10B of the main center 1A.
It has a function of notifying U10A of a write completion response. Then, the remote FCU 10 on the main center 1A side
Upon receiving a write completion response from the remote FCU 10B on the side of the sub-center 1B, A has a function of notifying the host 2A of the normal end when the writing is normally completed.

Next, the procedure of a remote transfer method by the remote FCU 10A performed in the present embodiment will be described in detail with reference to FIGS.
FIG. 2 shows the remote FCU 10A on the main center 1A side.
FIG. 6 is a sequence diagram for explaining a series of flows of remote transfer processing (remote DASD function) according to the first embodiment. When the host 2A uses the remote DASD function of the present embodiment, the host 2A specifies a virtual machine number (virtual volume),
A remote transfer designation write command (that is, a remote DASD operation command) is issued to the remote FCU 10A (see arrow A11).

In the remote FCU 10A, the CA 11 receiving the write command from the channel notifies the RM 12 of the activation from the channel (see arrow A12).
The RM 12 notifies the CA 11 that the designated machine number is a virtual volume (virtual machine number) (see arrow A13). The CA 11 that recognizes that the designated machine number is a virtual volume requests the CFE 15 to secure a cache area for storing data (write data to be written by the write command) (see an arrow A14). The CFE 15 recognizes that the data is not to be written to a volume under the present device (remote FCU 10A), secures a dedicated cache area in SS16, and notifies the CA 11 of completion of securing the cache area. (Arrow A15). At this time,
Since it is not necessary to store the data for a long time in the remote FCU 10A on the main center 1A side, an area of a non-volatile memory (NVS: NonVolatile Storage) is not secured.

Thereafter, when the CA 11 notifies the host 2A of the operability (see the arrow A16), the host 2A
Is written to SS16 through CA11 (see arrow A17). Upon completion of receiving the data from the host 2A, the CA 11 notifies the host 2A of the completion.
A and RM 12 are notified (see arrows A18 and A19).

Upon receiving the data reception completion notification, the RM 12
Since it is recognized that the designated machine number is a virtual volume, it instructs RA 14 to start remote transfer without instructing DA 17 to write data (see arrow A20). RA14 receiving this instruction
Reads the data to be transferred from the cache area of SS16, and transfers the data to the remote FCU 10B on the sub-center 1B side via the communication line 6 (see arrow A21).

On the sub center 1B side, the remote FCU 10
B, the data is written to the designated volume 4B, and when the data writing is completed normally, the primary center 1
The normal end is notified to the RA 14 of the remote FCU 10A on the A side (see arrow A22). When the remote FCU 10A on the main center 1A receives the normal end notification from the remote FCU 10B on the sub center 1B side at the RA 14, the RA 14 notifies the RM 12 that the remote transfer has been normally completed (see the arrow A23). ), The RM 12 notifies the data transfer completion to the CA 11 (see arrow A24). Further, CA11 is CFE15
Is requested to release the cache area (see arrow A25), and upon receipt of the notification of the completion of the release of the cache area from the CFE 15 (see arrow A26), the host 2A is notified that the remote DASD operation has been normally completed (see arrow A26). (See arrow A27).

As described above, according to the remote transfer method of the present embodiment, only the device number (virtual device number) of the virtual volume is valid in the remote FCU 10A on the main center 1A side, and the host 2A transmits a virtual volume number to the remote FCU 10A. When a write command designating a device number is issued, the write data according to the write command is transmitted to the host 2A on the primary center 1A and the remote FCU on the secondary center 1B.
10B is relayed and transferred by the remote 10A on the primary center 1A side, and written to the volume 4B existing on the secondary center 1B side.

That is, data writing to the volume of the main center 1A is suppressed, and a virtual machine number (virtual volume) that does not actually exist under the remote FCU 10A of the main center 1A appears to exist virtually. The software (the host 2A of the main center 1A) designates the virtual machine number and issues a write command, so that the current remote FCU 10A is used as it is and the main center 1A is used.
A remote DASD system in which data is written from the host 2A on the side to only the volume 4B on the side of the sub-center 1B can be realized.

The host 10A on the primary center 1A side
It is only necessary to issue a write command for designating a virtual machine number to the remote FCU 10A on the main center 1A side, so that conventional software for remote FCU can be used as it is, and software is newly developed separately. Eliminates the need. Further, the remote FCU 10A on the primary center 1A side and the remote FCU 1A on the secondary center 1B side
0B, a communication line 6 such as an ATM line from the RA 14
Therefore, there is no need to modify and provide dedicated converters for channels (reference numerals 20A and 20B in FIG. 8).

In this embodiment, it is not necessary to store write data by a write command specifying a virtual machine number in the remote FCU 10A for a long time.
By securing only the dedicated cache area in 16 and not securing the area of the nonvolatile memory (NVS), unnecessary overhead can be greatly reduced. Further, in the present embodiment, the remote FCU on the sub center 1B side
After the data transfer to the remote center 10A is completed, there is no need to leave the transfer data inside the remote FCU 10A on the primary center 1A side. Therefore, the cache area is more effectively used by immediately releasing the dedicated cache area in SS16. Can be used.

Further, according to the present embodiment, for example, when the main center 1A executes a business while updating the data in the volume 4A, and when the difference log accompanying the data update is stored as backup data, the above description is made. By using the remote DASD function, the backup data can be stored in the real volume 4B of the sub center 1B without storing it in the main center 1A. Therefore, it is necessary to provide a backup volume in the main center 1A. Is eliminated, which also contributes to cost reduction of the system.

It should be noted that the present invention is not limited to the above-described embodiment, and can be implemented with various modifications without departing from the spirit of the present invention.

[0051]

As described in detail above, according to the remote transfer method by the file control device of the present invention (claims 1 to 3), the following effects and advantages can be obtained. (1) As a method succeeding the remote MT, a remote DASD method of relaying by a file control device with a remote transfer function (remote FCU) can be realized.

(2) The host on the main center only needs to issue a write command for designating the machine number of the virtual volume to the file controller on the main center. Software can be diverted, and there is no need to separately develop software (claim 1). (3) The main center file control device and the sub center file control device are connected from the remote adapter module via a communication line such as a high-speed digital line or an ATM line, similarly to a normal backup system. It is not necessary to modify and provide a dedicated converter for the channel (claim 1).

(4) Since the write data by the write command specifying the virtual volume machine number does not need to be stored for a long time in the primary center-side file control device, only the dedicated cache area is secured and the data is nonvolatile. By not securing a memory area, unnecessary overhead is significantly reduced (claim 2). (5) After the data transfer to the secondary center file control device is completed in response to the write command specifying the virtual volume machine number, there is no need to leave the transfer data inside the primary center file control device, so immediately By releasing the dedicated cache area, the cache area can be utilized very effectively (claim 3).

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of a system to which a remote transfer method according to an embodiment of the present invention is applied.

FIG. 2 is a sequence diagram illustrating a procedure (remote DASD function) of a remote transfer method by a file control device according to an embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional configuration of a system including a main center for performing essential business and a sub-center for backup.

FIG. 4 shows remote FCs at a main center and a sub center
1 is a block diagram illustrating an example of a general configuration of a system in which U is connected by a communication line.

FIG. 5 is a block diagram showing a configuration of a general remote FCU.

FIG. 6 is a diagram for explaining a data flow at the time of remote transfer in the system shown in FIG. 4;

FIG. 7 is a diagram for explaining a remote transfer procedure in the system shown in FIG. 4;

FIG. 8 is a block diagram showing an example of a general configuration of a system employing a remote MT system.

[Explanation of symbols]

1A Primary center (business system) 1B Secondary center (backup system) 2A Primary center host computer (CPU) 2B Secondary center host computer (CPU) 3A Primary center FCU 4A Primary center volume (real volume) 4B Secondary center Volume (actual volume) 6 Communication line 10A Primary center remote FCU (primary center file controller, file controller with remote transfer function) 10B Secondary center remote FCU (sub center file controller, file control with remote transfer function) 11) CA (Channel Adapter) 12 RM (Resource Manager) 12a TS (Table Storage) 13 SA (Service Adapter) 13a TS (Table Storage) 14 RA (Remote Adapter) 15 CFE (Cache Function Engine) 16 SS (Shared Storage) ) 17 DA (Dev ice Adapter) 18 C-BUS (Control-BUS)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideo Takahashi 2-4-1-19 Shin-Yokohama, Kohoku-ku, Yokohama, Kanagawa Prefecture Inside Fujitsu Program Giken (72) Inventor Hideki Yamanaka 2-4-2, Shin-Yokohama, Kohoku-ku, Yokohama, Kanagawa No. 19 Inside Fujitsu Program Giken Co., Ltd. (72) Inventor Naomi Fujimoto 2-4-1 Shin Yokohama, Kohoku-ku, Yokohama City, Kanagawa Prefecture Inside Fujitsu Program Giken Co., Ltd.

Claims (3)

[Claims] 1. A file control device with a remote transfer function that operates in accordance with a command from a host computer on a main center side, and a file control device on the sub center side is a file control device on the main center side In the system connected to the control device via a communication line and configured to be able to write data from the file control device on the main center side to the volume, the system does not exist inside the file control device on the main center side. Is defined in advance as a device number of a virtual volume that is virtually treated as existing under the file control device of the main center, and the file control device of the main center defines the device number of the virtual volume as When the designated write command is received from the host computer on the main center, the write command Therefore, the data to be written is transferred to the sub-center side file control device via the communication line without writing to the main center side volume, and the sub-center side file control device causes the volume under the sub-center side to exist. A remote transfer method by a file control device, characterized in that the file is written to a file. 2. When a write command designating a device number of the virtual volume is received from the host computer on the main center in the file control device on the main center, the data to be written by the write command is received. 2. The remote transfer method according to claim 1, wherein only a dedicated cache area for storing the data is secured without securing a non-volatile memory area. 3. When the transfer of the data to the file control device of the sub-center is completed in the file control device of the main center, the dedicated cache area storing the data is immediately released. 3. The remote transfer method by the file control device according to claim 2, wherein: