JPH04299435A - Data base equivalent system - Google Patents

Abstract

PURPOSE:To perform the data base equivalent processing in a short period of time and with high efficiency. CONSTITUTION:In a working system the data base control parts 11 and 21 update the data bases 14 and 24 contained in their own computer systems 1 and 2 respectively and transfer the updating information to the computer systems 2 and 1 of a stand-by system through the communication control parts 13 and 23. If this transfer of information fits, the access keys of the date base records are stored in the untransferred data base record access key store files 15 and 25. When the rise information are received from the systems 2 and 1 of a stand-by system, the updating information corresponding to the access keys of both files 15 and 25 are transferred to the systems 2 and 1 of the stand-by system through the parts 13 and 23. In the stand-by system, however, the parts 11 and 21, update the bases 14 and 24 based on the updating information transferred from the systems 2 and 1 of the working system respectively after the stop state of the stand-by system is restored.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a database equivalence method in a standby switching computer system.

0002

[Background Art] Online data processing systems are equipped with two computer systems, one of which is used as a regular system and the other as a standby system, in order to ensure system reliability and continuity of operation against failures. A redundant configuration is adopted.

In such standby switching computer systems, not only the processing units but also the databases are often duplicated from the viewpoint of further improving reliability.

By the way, in a standby switching computer system in which the database is duplicated, it is necessary to make the standby database equivalent to the regular database. If this is not done, the operation will not be able to continue when switching to the standby computer system in the event of a failure in the regular computer system.

In this regard, while the standby computer system is operating, all input information to the regular computer system is sent to the standby system, or the updated contents of the regular database are sent to the standby system. By transferring the data to the computer system, equivalence of the databases between both computer systems is guaranteed.

However, while the standby computer system is out of operation, the databases of both computer systems cannot be updated almost simultaneously as described above, so the database on the regular computer system cannot be updated. If updated, there will be a difference between the two.

Conventionally, when one computer system is stopped or moved from an offline state to a standby system, the contents of all databases that may be updated while online are transferred from the regular system, and the database The equivalence of was realized.

[0008]

[Problems to be Solved by the Invention] As mentioned above, in the database equivalence method in the conventional standby switching computer system, it is difficult to determine how much the database was actually updated while one computer system was stopped. Regardless, when the computer system starts up and moves to the standby system, all database contents that may be updated will be transferred from the regular system, so there is a lot of waste in processing and the processing time is long. There was a drawback that it took a long time.

The present invention has been proposed in view of the above points, and its purpose is to provide a database equivalence method that is efficient and requires less processing time by transferring data to the minimum necessary level. There is a particular thing.

0010

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a standby switching computer system having a computer system operating as a regular system and a computer system operating as a standby system. , a communication management unit that executes and manages data communication between computer systems, and in the case of a regular system, updates the database within the own system, and transfers the updated information to a standby computer system by the communication management unit, and then Store the access key of the failed database record in the untransferred database record access key storage file, and correspond to the access key of the untransferred database record access key storage file when receiving notification that the standby computer system has started up. A database management unit that transfers update information to a standby computer system by a communication management unit, and updates the database based on the update information transferred from the regular computer system in the case of a standby system or when recovering from a stopped state. , monitors and controls the operating status of the computer system, processes the transition to the regular system or standby system, and when the computer system recovers from the stopped state, the communication management unit notifies the regular computer system that the system has started up. The system also includes a system status monitoring control unit that notifies the user of the system status.

[0011]

[Operation] In the database equivalence method of the present invention, when the database management unit is a regular system, it updates the database in its own system, and the communication management unit transfers the updated information to the standby computer system. If the transfer fails, the access key of the database record is stored in the untransferred database record access key storage file, and when a notification that the standby computer system has started up is received, the untransferred database record access key storage file is stored. Update information corresponding to the access key is transferred to the standby computer system by the communication management unit. Also, in the case of a standby system or when recovering from a stopped state,
The database management unit updates the database based on update information transferred from the regular computer system. On the other hand, the system status monitoring control unit monitors and controls the operating status of the computer system, processes the transition to the regular system or standby system, and when the computer system recovers from the stopped state, the communication management unit automatically switches the computer system to the regular system. Notify that the system has started up.

0012

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing an embodiment of a standby switching computer system to which the database equivalence method of the present invention is applied.

In FIG. 1, this embodiment has a computer system 1 and a computer system 2, and each computer system 1, 2 has a database management section 11, 2.
1, system status monitoring control unit 12, 22, and communication management unit 1
3, 23, databases 14, 24, and untransferred database record access key storage files 15, 25 are provided. Note that the functions of each part will be explained through the following operations to avoid duplication.

The operation of the above embodiment will be explained below with reference to the flowcharts of FIGS. 2 and 3.

Now, suppose that computer system 1 is a regular system, computer system 2 is a standby system, and both computer systems 1 and 2 are in operation.

When online database update processing is performed in this state, first, the regular computer system 1
, the database management unit 11 updates the database 14 in response to a processing request from a user (step 101), and sends update information indicating the content of the update to the communication management unit 13.
give to

The communication management unit 13 transfers the updated information to the standby computer system 2 (step 102).

In the computer system 2, the communication management section 2
3 receives update information (step 201) and provides the update information to the database management section 21.

The database management unit 21 updates its own database 24 according to the update information (step 2
02).

The above is the normal database update process and equivalent process.

Next, suppose that the computer system 1 stops operating for some reason in this state (step 103).

The system status monitoring control unit 22 of the computer system 2 detects the stoppage of the computer system 1 (step 2).
03), the own computer system 2 is transferred to the regular system (step 204).

If it becomes necessary to update the database in this state, the database management unit 21 of the computer system 2 that has become the regular system updates the database 24 in response to the processing request (step 205), and transmits the updated information through communication management. Part 2
Give to 3.

The communication management unit 23 attempts to transfer the update information to the computer system 1 (step 206).

However, since the computer system 1 has stopped operating, the data cannot be accepted and the transfer will fail. The communication management unit 23 detects this (step 207) and sends the data to the database management unit 21. convey the message.

The database management unit 21 writes the access key of the database record whose transfer failed to the untransferred database record access key storage file 25 (step 208). Note that if the database update occurs multiple times, steps 205 to 208 will be repeated. However, if the same database record is updated multiple times, the access key will be newly stored in the untransferred database record access key storage file 25. There is no need to register.

After that, when the computer system 1 starts up again (step 104 in FIG. 3), the system status monitoring control unit 12 sends a communication request to have the computer system 2 transfer the database update information for transition to the standby system. The management unit 13 is ordered to notify the computer system 2 of start-up information.

The communication management unit 13 notifies the computer system 2 of start-up information in response to the command (step 105).
.

The communication management unit 23 of the computer system 2 receives the information (step 209) and starts the database management unit 21.

The database management unit 21 reads the contents of the untransferred database record access key storage file 25 (step 210), and retrieves the access key of the database record for which transfer has failed (step 211).
), reads the contents of the corresponding record in the database 24 (step 212), and provides the contents to the communication management section 23.

The communication management unit 23 transfers the contents of the database record whose transfer failed to the computer system 1 (step 213).

When one transfer is completed, the database management unit 21 refers to the contents of the previously read untransferred database record access key storage file 25 to determine whether the transfer of all necessary records has been completed. Confirm (step 214), and if there are other records that need to be transferred, repeat steps 211 to 214, and if all are completed, notify the communication management unit 23 to that effect, and the communication management unit 23 will send a message to the computer system 1. to notify the end of the transfer (step 215).

Then, the database management unit 21 clears the untransferred database record access key storage file 25 (step 216).

On the other hand, the communication management section 13 of the computer system 1
waits for the update information to be received from the computer system 2, and when the data is received (step 106), it determines whether the content is the database update content or a transfer completion notification (step 107), and if the data is the database update content, the database The management unit 11 updates the database 14 (
In step 108), the communication management unit 13 waits for data reception again.

If the content received from the computer system 2 is a transfer end notification, the system status monitoring control unit 12 performs other processing to become a standby system, and
is transferred to the standby system (step 109).

Through the above processing, computer systems 1 and 2
Equivalence processing of the databases 14 and 24 is performed.

[0037]

[Effects of the Invention] As explained above, in the database equivalence method of the present invention, when both the regular and standby computer systems are operating, the database is updated almost simultaneously, and the standby and standby computer systems are updated at the same time. If the target computer system is not operating, store the access key of the updated database record in the regular untransferred database record access key storage file.
When the computer system that has been stopped is started up, the update information is retrieved and transferred based on the access key stored in the untransferred database record access key storage file, and the database is updated, so the minimum data transfer is possible. This has the effect that unnecessary data transfer can be omitted and the time required for database equivalence processing can be shortened.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a standby switching computer system to which the database equivalence method of the present invention is applied.

FIG. 2 is a flowchart showing an example of the operation of the embodiment.

FIG. 3 is a flowchart following FIG. 2;

[Explanation of symbols]

1, 2...Computer system 11, 21...Database management unit 12, 22...System status monitoring control unit 13, 23...Communication management unit 14, 24...Database 15, 25...Untransferred database record access key storage file

Claims (1)

[Claims] Claim 1: In a standby switching computer system having a computer system operating as a regular system and a computer system operating as a standby system, each computer system includes a communication management unit that executes and manages data communication between the computer systems. In the case of a regular system, the database within the own system is updated, the updated information is transferred to the standby computer system by the communication management section, and the access key of the database record that failed to be transferred is stored as the access key of the untransferred database record. The update information corresponding to the access key in the untransferred database record access key storage file is transferred to the standby computer system by the communication management section when the standby computer system receives a notification that the access key has been started up. , a database management unit that updates the database based on update information transferred from the regular computer system in the case of a standby system or when recovering from a stopped state, and a database management unit that monitors and controls the operating status of the computer system and Alternatively, the computer system is characterized by comprising a system status monitoring control unit that processes the transition to a standby system, and when the computer system recovers from a stopped state, the communication management unit notifies the regular computer system that the system has started up. database equivalence method.