JPH07105065A - Back-up method for data - Google Patents

Abstract

PURPOSE:To uniformly execute back-up without being restricted by the number of volumes by deciding the execution order of back-up for the respective volumes and executing update with the execution order of the volume whose back-up is failed as the head. CONSTITUTION:A magnetic disk device 12 is provided with a system volume 12a and a user volume 12b. A magnetic tape for back-up is mounted on a magnetic tape device 13. Identification information showing the high-order volume is extracted from an order table 21 and an execution table 22 is generated. Then, the volume concerned is backed up based on the execution table 22. When back-up is succeeded, the record of identification information is updated after the order table 21. When back-up is failed, the record of the identification information is updated first. Thus, the back-up of the volume, which is failed, is taken precedence in next back-up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of backing up data stored in a magnetic disk device or the like in a plurality of units in units of volumes.

In a computer system, regular backup is indispensable for important data stored in a magnetic disk device or the like. Backup is generally performed in logical volume units, but if the entire logical volume that is the backup target cannot be backed up once (1 day), it can be divided into multiple times (multiple days) to selectively perform backup. There is a need to do. In that case, it is desirable that backup be performed as evenly as possible for all logical volumes.

[0003]

2. Description of the Related Art Conventionally, a day of the week is used as a key for performing selective backup.

That is, for example, all the volumes to be backed up are divided into seven times from Monday to Sunday, and the volumes assigned on each day of the week are backed up.

The backup is automatically executed after the work of the day is completed, for example, by the operator mounting a magnetic tape corresponding to the volume of the day on the magnetic tape device. The number of volumes for one time (one day) is determined in consideration of the processing capacity of the computer system so that the backup is completed by the start of the work on the next day.

[0006]

However, according to the above-mentioned conventional method, when the backup is unsuccessful, the volume is not backed up for one week until the next same day. .

For example, if a predetermined magnetic tape for backup is not properly mounted in the magnetic tape device, or if the volume is still used after the work is completed, the backup cannot be collected. Such a backup failure sometimes occurs, but in that case, the backup of the volume must be waited until the next week, and the backup for each volume is not even.

Further, in the method of dividing the backup target of the current day by the day of the week, the schedule can be created only for a maximum of seven patterns. Therefore, there is a limit to the number of volumes that can be backed up, and if there are more volumes than that, a schedule cannot be created. For example, if the number of backups that can be performed at one time is 3, and if the volume exceeds 21 (= 7 × 3), a schedule cannot be created.

In this case, it is conceivable to create a schedule every other week or every month, but in that case, the backup interval may be too long,
It is not possible to create a detailed schedule according to the number of target volumes. Further, since the schedule becomes complicated, it is easy for a magnetic tape mount error for backup to occur.

The present invention has been made in view of the above-mentioned problems, and provides a backup method in which the number of volumes that can be backed up is not limited and backups are evenly performed to the target volumes. The purpose is to provide.

[0011]

According to a first aspect of the present invention, there is provided a method of backing up data stored in a plurality of volumes to be backed up on a volume-by-volume basis. The order is determined in advance, and each time the backup is executed, the backup is executed for the specified number of volumes that are in the higher order of execution, and the backup is not performed because the execution order of the volume for which the backup was successful is the last. This is a backup method in which the execution order of the volume that has been successful is updated first, and the next backup is executed according to the updated execution order.

In the method according to the second aspect of the present invention, as shown in FIGS. 1 to 3, the identification information NV indicating each volume is set as one record, and the execution order of backup is indicated by these plural records. The ranking table 21 is created, and each time the backup is executed, the backup of the volume corresponding to the predetermined number of records in the higher execution order is executed, and the records of the volumes for which the backup was successful are executed. A backup method in which the order table 21 is updated so that the order of execution is the last and the order of execution of the volume for which the backup was unsuccessful is first, and the next backup is executed based on the updated order table 21. Is.

In the method according to the third aspect of the present invention, each time a backup is executed, a predetermined number of records in the higher order of execution are extracted from the order table 21 to create the execution table 22, and the execution table 22 is executed. The backup of each volume is executed based on the table 22, and the execution order of the record of the volume for which the backup was successful is at the end, and the execution order of the volume for which the backup is unsuccessful is at the top. The ranking table 21 is updated, and the updated ranking table 21
It is a backup method that executes the next backup based on.

[0014]

The identification information (for example, volume name) NV indicating a predetermined number of high order volumes is extracted from the order table 21, and the execution table 22 is created by the extracted identification information NV, for example.

Backup of the corresponding volume is executed based on the execution table 22. When the backup is successful, the record of the identification information NV is updated so as to be the tail of the ranking table 21, and when the backup is unsuccessful, the record of the identification information NV is the head of the ranking table 21. Will be updated.

Therefore, in the next backup, the backup of the volume that failed in the current backup is preferentially performed again.

[0017]

1 is a block diagram of a computer system 1 according to the present invention. The computer system 1 is composed of a host 11, a magnetic disk device 12, a magnetic tape device 13, a terminal device 14, and the like.

The magnetic disk device 12 is provided with a system volume 12a and a plurality of user volumes 12b as logical volumes, and the data processed by the host 11 for the user is one of the user volumes. It is stored in 12b. An order table 21 (21a, b ...) Is stored in the system volume 12a, and an execution table 22 (22a, b ...) Created when the computer system 1 is started up.
Is stored.

A magnetic tape for backing up the user volume 12b is mounted on the magnetic tape device 13. The mount of the magnetic tape is performed by the operator for the backup of the day before the end of the work. A label indicating the volume name NV is attached to the backup magnetic tape. 1
When multiple magnetic tapes are required for each volume, for example, "usr7
A serial number is added after the volume name, such as "1""usr72".

When the operator inputs a command, the terminal device 14 displays the volume name NV to be backed up on the day, that is, the contents of the execution table 22 on the screen HG.

FIG. 2 is a diagram showing the ranking table 21, and FIG. 3 is a diagram showing transition states of the contents of the ranking table 21 and the execution table 22. In FIG. 2, the ranking table 21
For each volume to be backed up in the user volume 12b, each volume name NV is set as one record, and those records are arranged according to the backup execution order.

In the example of FIG. 2, the volume name NV "usr7" of the volume for which the backup is given the highest priority is located at the head, and the second and subsequent volumes are "usr2" and "usr1".
… Continued.

Next, a backup method in the computer system 1 will be described with reference to the flowcharts shown in FIGS. 3 and 4. Note that, here, the number n of volumes to be backed up at one time is “3”.

First, the upper three records of the ranking table 21 are extracted, the execution table 22a is created by the extracted records and stored in the system volume 12a (# 1).

The record extracted from the ranking table 21 is deleted, and this becomes the ranking table 21a (#
2). If there is a record in the execution table 22 (# 3
And yes) read one record (# 4). In the example of FIG. 3, “usr7” is read from the execution table 22a.

The backup of the volume indicated by the read record is executed (# 5). In the example of FIG. 1, the user tape 12b to the magnetic tape device 13
Is backed up.

When the backup is completed normally (Yes in # 6), the record is placed in the ranking table 21a.
Insert it at the end (# 7). In the example of FIG. 3, “usr
Since the backup of "7" is normally completed, the rank table 21a becomes the rank table 21b, and the execution table 22a becomes the execution table 22b.

When the backup is not normally completed (No in # 6), the record is placed in the ranking table 21.
To the beginning (# 8). In the example of FIG. 3, since the backup of “usr2” has not been normally completed, the ranking table 21b becomes the ranking table 21c.

Then, step # 3 and subsequent steps are repeated,
When there are no records in the execution table 22 (No in # 3), the processing is terminated and the computer system 1 is stopped. In the example of FIG. 3, the backup of “usr1” also ends normally, and the final ranking table 21d is created.

When the backup is performed next time (next day), the upper three records of the ranking table 21d are extracted, and the execution table 22 arranged in the order of "usr2", "usr5", and "usr6" is created. It Therefore, next time, backup is performed again for "usr2" for which backup acquisition failed last time. The execution table 22 is automatically created when the computer system 1 is started up at the start of work on the next day.

As described above, since the volume for which the backup has failed is backed up again in the next time, the backup is equally performed for all the volumes regardless of the success or failure of the backup. There is no backup available for a week. Further, there is no limit to the number of volumes to be backed up, and by registering the volume name NV in the ranking table 21, even backup is performed regardless of the number of volumes. Therefore,
You can freely create a schedule without being restricted by the days of the week as in the past.

If backup of the same volume fails in succession, some kind of warning may be displayed. By doing so, the failure of the magnetic tape for backup can be found early.

In the above-described embodiment, the backup order is determined and executed based on the order table 21 and the execution table 22, so that the backup process can be performed reliably, but the order table and the execution table having different configurations from those described above. Backup may be performed with or without such a table.

In the above embodiment, the computer system 1
Each unit may be composed of one unit or a plurality of units. The configurations of the rank table 21 and the execution table 22, the contents and order of the flowchart, the configuration of the computer system 1, and the like can be variously changed in accordance with the gist of the present invention.

[0035]

As described above, according to the present invention, it is possible to provide a backup method in which the number of volumes that can be backed up is not limited, and backups are evenly performed to the target volumes.

According to the third aspect of the present invention, the backup process can be reliably performed.

[Brief description of drawings]

FIG. 1 is a block diagram of a computer system according to the present invention.

FIG. 2 is a diagram showing a ranking table.

FIG. 3 is a diagram showing a transition state of contents of a ranking table and an execution table.

FIG. 4 is a flowchart showing a backup procedure.

[Explanation of symbols]

 21 Order table 22 Execution table NV volume name (identification information)

Claims (3)

[Claims] 1. A method of backing up data stored in a plurality of volumes to be backed up on a volume-by-volume basis, wherein a backup execution order is determined for each volume, and backup is executed each time the backup is executed. , Backup is performed for a specified number of volumes that are higher in the execution order, and the execution order of the volume for which the backup was successful is updated at the end, and the execution order of the volume for which the backup is unsuccessful is updated at the beginning. Then, the data backup method is characterized in that the next backup is executed according to the updated execution order. 2. A method of backing up data stored in a plurality of volumes to be backed up in volume units, wherein identification information (NV) indicating each volume is set as one record, and backup is executed by these plurality of records. A rank table (21) indicating the rank is created, and each time the backup is executed, the backup of the volume corresponding to the predetermined number of records in the higher execution order is executed, and the backup is successful. The order table (21) is updated so that the execution order of the record for the volume is at the end and the execution order of the volume for which the backup was unsuccessful is at the top, and based on the updated order table (21) Backup of data characterized by performing the next backup Up method. 3. A method for backing up data stored in a plurality of volumes to be backed up on a volume-by-volume basis, wherein identification information (NV) indicating each volume is defined as one record, and backup is executed by these plurality of records. A ranking table (21) indicating the ranking is created, and a predetermined number of records in the higher ranking of execution are extracted from the ranking table (21) each time a backup is executed, and the execution table (22) is created. Create and execute a backup of each volume based on the execution table (22), and execute the volume for which the backup was unsuccessful so that the order of record execution for the volume for which the backup was successful is at the end. Update the ranking table (21) so that the ranking is at the top, and Backup method of data and executes the next backup based on ranking table (21) which is.