JPH0459649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for moving data stored in a direct access storage device to another direct access storage device with different specifications, and in particular to a method for moving data stored in a direct access storage device to another direct access storage device with different specifications. The present invention relates to a data movement method suitable for moving data using a certain magnetic tape or the like as a medium.

[Prior art]

Transfer data stored in a direct access storage device (old device) to another direct access storage device with different specifications (new device), generally a direct access storage device with a large storage capacity, such as magnetic tape, which is a sequential access storage device. If the data is moved using the old device as a medium, the specifications of the old device and the new device are different, so if the data is simply moved, there is a problem that the data storage area (storage area) of the new device cannot be used effectively. Specifically, old devices, such as magnetic disks (referred to as old magnetic disks), have fixed specifications such as track length and number of tracks per cylinder depending on the model. New devices, such as magnetic disks (referred to as new magnetic disks),
Track length, number of tracks per cylinder, etc. have fixed specifications depending on the model. If the specifications of the old magnetic disk and the new magnetic disk are different, the information that manages the data on the old magnetic disk, such as the cylinder number and head number that indicate where on the old magnetic disk the data is stored, will be lost to the new magnetic disk. If you use the new magnetic disk to store data on the new magnetic disk, especially if the new magnetic disk has a large capacity, you will not be able to use enough storage space on the new magnetic disk.
Inefficient.

For this reason, the conventional solution for effectively using the storage area of a new device is to either have the operator perform desk calculations to allocate the storage area of the new device, or to go further and save the data stored on the old magnetic disk. When moving and storing data on a new magnetic disk, when saving data from the old magnetic disk, data area information (cylinder number, cylinder number,
The area required for the new magnetic disk is calculated based on the area information of the new magnetic disk given with the saved data (head number, etc.) and the area information about the old magnetic disk, and the area required for the new magnetic disk is calculated based on the area. There is a data movement method that moves data to disk.

Incidentally, related data transfer methods of this type include, for example, Japanese Patent Application Laid-open No. 43736/1983.

[Problem that the invention seeks to solve]

In the above-mentioned conventional technology, in preparation for a failure or the like occurring during data movement, a backup magnetic tape is generally prepared in addition to the magnetic tape used as a medium between the old device and the new device. This will be explained using FIG. old magnetic disk 1
1 has a directory block in which data is stored in the form of member blocks and manages the recording positions of the member blocks as area information. The mediating magnetic tape 12 is output in the order of members A, B, and C managed by the directory block of the old magnetic disk 11. On the other hand, on the backup magnetic tape 13, members are recorded in the order in which they are recorded, here C, A, B, regardless of the directory. The operator is
Taking into consideration the storage capacity of the new magnetic disk 14, the storage area for the data members is calculated, and the members are stored and managed in a new directory.

In this way, the conventional data movement method uses two magnetic tapes: the magnetic tape 12 that mediates data from the old magnetic disk to the new magnetic disk, and the magnetic tape 13 for backup as a backup. It was the economy.

Further, the old magnetic disk 11 reads data from the member block in the order of the beginning of the directory, in the order of A, B, C in FIG. Therefore, there was a problem in that it took longer to record than the backup magnetic tape 13, which records data directly in the order of member blocks. Furthermore, considering the data usage frequency and data access time, data C,
Members of the new magnetic disk 14 in the order of A and B.
If it is desired to store data in the order of C, A, B in the block as well, it is very inconvenient to use the medium magnetic tape 12. This is because data members are recorded on the medium magnetic tape 12 as A, B, and C in the directory order of the old magnetic disk 11.
C on the member block of new magnetic disk 14,
If you want to store data in the order of A, B, then operate the medium magnetic tape 12 to store data C, A,
Since the data will be read in the order of B, it will take a considerable amount of time to migrate the data.

The above-mentioned conventional technology has problems in that data migration is uneconomical and requires a lot of time.

The purpose of the invention is to be economical, time saving and
The purpose is to provide a hassle-free data movement method.

[Means to solve the problem]

In the past, attention was paid to backup magnetic tapes that were prepared as a backup in case of failures, etc., and data was moved using a single backup magnetic tape. However, even if you simply store the data recorded on magnetic tape in the member block order of the old magnetic disk to the member blocks of the new magnetic disk, the directory that manages the area information for each member on the new magnetic disk will not be created. cannot be created. Therefore, the backup magnetic tape is made to hold the directory of the old magnetic disk, that is, the data area information, and the data members of the directory are arranged in the order in which the data is stored.
A member management table sorted in block order is created inside the processing device involved in data movement work. After storing the data on the new magnetic disk, the information regarding the area of the new magnetic disk is made to correspond to the member management table, and is rewritten with the area information of the old magnetic disk. Furthermore, the member management table is rearranged in the order of the members of the directory of the old magnetic disk, and this is updated as the directory of the new magnetic disk, thereby completing the data movement.

By implementing the solution described above, the object of the present invention is achieved.

[Effect]

The data movement method of the present invention moves data from an old device to a new device, and records the data on a sequential access storage device, such as a magnetic tape, in the order in which data is stored in the old device. , also records the data index and data area information of the old device, stores the data in the new device, associates the information about the stored data area with the data index of the old device, and stores the data of the old device. By rewriting the area information, a data index and area information for the new device are created and used as the index area for the new device, making it possible to move data reliably and easily.

〔Example〕

Hereinafter, one embodiment of the present invention will be described using FIGS. 1 to 4.

FIG. 3 is a schematic diagram of a system configuration in which the data movement method of the present invention is implemented. 21 is an old magnetic disk that contains the data to be moved. The magnetic disk has a directory block and a member block, as shown in FIG. A member block is a set of data members, and a directory block is a part that manages area information regarding areas in which individual data members are stored. Furthermore, the directory has an index section that manages data member names, and a storage area information section that holds information indicating where each data member is stored, such as relative track number (hereinafter referred to as TTR). It consists of Reference numeral 25 denotes a data processing unit, which is a part where the data movement method of the present invention is mainly carried out.
The data processing section 25 also includes a data saving processing section 22 and a data restoration processing section 24. The data save processing unit 22 saves data from the old magnetic disk 21 and records it on the magnetic tape 23. The data restoration processing unit 24 restores the data recorded on the magnetic tape 23 and stores the data on the new magnetic disk 26.
This is what you write in.

Next, regarding the process of data movement,
This will be explained using the schematic diagram in FIG. 1 and the flowchart in FIG.

The old magnetic disk 21 is in the form of a partitioned data set, in which directories are recorded in key order and members are recorded arbitrarily. Generally, the member with the greater number of I/Os is placed at the top. Here, the directories are in the order A, B, C, and the members are C, A,
The order is B. When backing up data on the old magnetic disk 21 to the magnetic tape 23, the directory portion is recorded as is, for example at the beginning of the magnetic tape. The directory member names are A,
The order is B and C. Further, the member block portions are also recorded on the magnetic tape 23 as they are in the order of the recorded positions. Therefore, on the magnetic tape 23, the order of members is C, A, and B.

Next, a processing procedure for moving data from the backup magnetic tape 23 to the new magnetic disk 26 in the data processing section 25 will be explained.
Start the data movement process (step number
100). First, a portion of the backup magnetic tape 23 corresponding to the directory is copied to the directory 8 of the new magnetic disk 26 (101). At this time, in the data processing section, the member name and
A member management table 4 having TTR (relative track number) information is created and chained in order of member names (101). In this case, the member management table 4 has the order of A, B, and C. When the above processing is completed for all directories (102), the member management table is sorted in order of TTR (103). In FIG. 1, when the member management table is sorted in order of TTR, the order is C, A, and B.

Next, the members of the backup magnetic tape 23 are
The portion corresponding to the block is copied to the member block of the new magnetic disk 26 (104). In other words, member records are copied in TTR order. Therefore, the data on the new magnetic disk 26
In the block, data members are stored in the order of C, A, and B. During this data movement, information regarding the TTR of the old magnetic disk 21 is extracted to the data processing unit 25, and information about the TTR of the old magnetic disk 21 is extracted.
Create a TTR list (this is called the old TTR list 6). The old TTR list 6 has member records C, A, and B in this order. Furthermore, when a data member is stored in the member block of the new magnetic disk 26, the TTR of the new magnetic disk 26
A list (new TTR list 7) is created and compared with old TTR list 6 (104). The new TTR list 7 is
Although no member names are given, the order of the members should be C, A, and B. When copying all members and creating the TTR list are completed (105), an EOF record is output at the end of the data to indicate the end of the file (106).

Next, updating of the directory 8 of the new magnetic disk 26 will be explained. The member management table 5 mentioned above is sorted in TTR order, but the TTR information it holds is related to the old magnetic disk 21. Therefore, the TTR information regarding the new magnetic disk 26 in the new TTR list 7 is rewritten in the member management table 5. (106) Both member management table 5 and new TTR list 7 have members C, A, and B.
Since they are arranged in the order of , and can be associated with each other, rewriting can be done easily. After the new TTR information is rewritten in the member management table 5 in TTR order (106), this member management table 5 is again sorted in order of member name (107). Now, the information necessary to create the directory 8 of the new magnetic disk 26 is complete. Since the directory of the old magnetic disk 21 is copied as is to the directory 8 of the new magnetic disk 26 (101), the directory 8 that manages the member blocks of the new magnetic disk 26 is created according to the member management table 9 ordered by member name. Update (108). This completes the data movement process (109).

According to this embodiment, when data is moved via magnetic tape, there is no need to record it on the magnetic tape in the order of directory blocks, so data can be recorded on standard backup magnetic tape in the order of the recording position of the data blocks. Because data can be moved to new magnetic disks, there is no need for both conventional magnetic tape for media and magnetic tape for backup, and only one type of magnetic tape for backup is sufficient, reducing the number of magnetic tapes. will be reduced. Furthermore, data can be moved to the new magnetic disk in the same directory order and member storage order as the old magnetic disk, and the system migration process can be completed in a short time, making the process simple and time-saving. It has the effect of just doing the work.

〔Effect of the invention〕

According to the present invention, data can be moved using only the backup magnetic tape without using two types of conventional media magnetic tape and backup backup magnetic tape. Since the block portion is recorded as it is on the magnetic tape and the member block portion is stored as is on the new magnetic disk, it is economical, time saving, and labor-saving.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an overview of data movement processing in the data processing unit, Fig. 2 is an explanatory diagram of a conventional data movement method, and Fig. 3 is a hardware configuration of an application of the data movement method according to an embodiment of the present invention. 4 are flowcharts of a data movement method according to an embodiment of the present invention. Explanation of symbols, 4...Member management table in order of member name, 5...Member management table in order of TTR,
6... Old TTR list, 7... New TTR list, 2
1... Old magnetic disk, 22... Data backup processing unit, 23... Backup magnetic tape, 24...
Data restoration processing section, 25...Data processing section, 26
...New magnetic disk.

Claims (1)

[Scope of Claims] A sequential access storage device starting from one direct access storage device having a data storage section for storing data and an area information section for managing area information indicating a storage area of the data in the data storage section. In a migration method of moving data to another direct access storage device using a storage device as a medium, the area information is recorded in the sequential access storage device, and the data is transferred in the order in which the data is recorded in the sequential access storage device. record,
Further, the area information of the first direct access storage device stored in the sequential access storage device is extracted and rearranged in the data storage recording order, and the data recorded in the sequential access storage device is directly transferred to the other direct access storage device. At this time, information regarding the data storage area in the other direct access storage device is generated, and the area information rearranged in the order of data storage recording is rewritten with the generated information. A data movement method characterized in that area information is written as area information of the other direct access storage device.