JP2012068891A - Hierarchical storage system and data archive method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a hierarchical storage system capable of transferring data efficiently and properly from a primary storage to a secondary storage taking into account a difference between archive and backup.SOLUTION: A hierarchical storage system comprises: a backup control part which backs up data recorded in a primary storage; and a file information management part which manages information relative to the kind and operation of the data. A secondary storage comprises: an optical disk device which performs recording and reproduction with an optical disk exchangeable with a hard disk; and an archive control part which records a part of the data backed up in a hard disk in an optical disk based on the information relative to the kind and operation of the data.

Description

  The present invention relates to a storage apparatus, and more particularly to a data migration method in a hierarchical storage system.

  As a background art, for example, there is a technique described in Patent Document 1 (Japanese Patent Laid-Open No. 2008-40699). In Patent Document 1, “as data snapshot creation processing, file data that has not been archived out of file data in the primary storage 1 is saved to the secondary storage 2” and “record in the name space information table 142” Among them, a record whose target generation number is included in the valid generation number range is extracted, and a file corresponding to the extracted record is set as a restore target file.

JP 2008-40699 A

  Hierarchical storage systems include high-transfer-rate storage (primary storage) such as hard disk devices, and storage (secondary storage) such as optical disk devices and magnetic tape devices that record and reproduce information on interchangeable information recording media. In combination, it constitutes an inexpensive and large capacity file system.

  In the tiered storage system, data that has just been generated or data that is frequently accessed is stored in the primary storage, but data that has been accessed less frequently is transferred to the secondary storage and stored. It is desirable that the secondary storage has a longer media life than the primary storage, and data migration from the primary storage to the secondary storage is called archive.

  On the other hand, for primary storage, a copy of the data is regularly created (backed up) in preparation for data loss due to human error such as user error, external attack via network, disaster, etc. Used for data recovery. Especially for data with many changes, backup can be performed with snapshots that save the state at a certain point in time, and it is possible to recover to the state of any generation by holding snapshots at multiple points in time (generation) To do.

  Japanese Patent Laid-Open No. 2008-40699 described above is an example of a prior art that enables data to be archived when a backup is performed using a snapshot, and that the data can be recovered using the archived data.

  In order to improve backup efficiency, a full backup, which is a backup of all data at a certain point in time, is performed, and after that, only data that has changed such as addition, deletion, rewriting, etc. is backed up. There is a technique called incremental backup.

  In a tiered storage system, secondary storage is used for two different purposes: archiving to store data that has been used less frequently for a long period of time and backup to prepare for unforeseen circumstances. The required storage period differs between data for backup and data, and the former is a period of several to several tens of years, for example. A week may be sufficient.

  In addition, data that requires archiving and data that requires backup are not necessarily the same type of data. The former is centered on user-created content, whereas the latter is frequently updated. Data that is automatically generated and used by an operating system (OS) and application programs is important.

  The technique described in Patent Document 1 described above is a technique that makes it possible to perform archiving and backup in a unified manner, but the difference between the two data as described above is not taken into consideration, and all the data is stored. It was only accumulated cumulatively in secondary storage without distinction. As the accumulated data increases, data management becomes more difficult.

  The present invention has been made in view of the above, and an object of the present invention is to enable efficient and appropriate data migration from primary storage to secondary storage in consideration of the difference between archive and backup. It is to realize a tiered storage system.

  In order to solve the above-described problems, the present invention uses the configuration described in the claims as an example.

  According to the present invention, it is possible to realize a hierarchical storage system that can efficiently and appropriately transfer data from a primary storage to a secondary storage in consideration of the difference between archive and backup.

Flow chart of backup operation in the first embodiment Block diagram of the hierarchical storage system in the first embodiment Block diagram of the hierarchical storage system in the second embodiment Flow chart of backup operation in the second embodiment

  Embodiments of a hierarchical storage system according to the present invention will be described below with reference to the drawings.

  The configuration and operation of the hierarchical storage system as the first embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 2 is a block diagram of the hierarchical storage system in the first embodiment. The hierarchical storage system of this embodiment is configured across two devices. One is the host computer 10 and the other is the secondary storage device 20.

  The host computer 10 includes a primary storage 12 that is a hard disk device as an internal storage device, and a controller 11 that controls the primary storage.

  As part of the controller 11, the file information manager 14 manages file information of files recorded in the primary storage 12. The file information includes the directory structure and file name for identifying the file, the file type, the backup candidate flag indicating whether or not it is a backup candidate, the number of times each file has been played during a predetermined period, and whether or not an archive file has been created. And a unique file ID for the archive destination file. The backup candidate flag is turned on / off according to the operation type and operation date / time for each file. File operations include generation, deletion, name change, and overwrite. The predetermined period is the shorter of the period after the previous backup is performed and the period after the file is generated or overwritten. The file information database is recorded in the primary storage as a metafile. Note that the file information is retained while retaining the directory structure before deletion even for a file archived in the secondary storage and deleted from the primary storage.

  Further, as a part of the controller 11, the backup manager 13 manages the backup of the primary storage. Backup by snapshot is performed in accordance with the backup policy set by the user, and generation management information for generation management of data of the primary storage 12 and backup is created and output to the secondary storage apparatus 20. For example, a full backup is performed once a month, the changed data is extracted from the latest full backup with reference to the backup candidate flag of the file information described above, and a differential backup is executed every day at a predetermined time. The generation management information includes a generation number of a base full backup, a current generation number of a differential backup, a list of differential files including files that have been deleted or renamed, and file operation information. In addition, the file information related to the file is included. Note that all files are targeted for full backup.

  The secondary storage device 20 is an external storage device for the host computer 10, and includes a hard disk device 22 that functions as a buffer, an optical disk device 23 that performs recording and reproduction on an optical disk that is a replaceable information recording medium, and these hard disk devices 22. And a secondary storage controller 21 for controlling the optical disk device 23.

  As part of the secondary storage controller 21, the archive manager 24 manages archiving processing to the write-once optical disc 1 for files recorded in the hard disk device 22. A database of archive management information, which is an execution result of archive processing, is recorded in the hard disk device 22 as a metafile. The archive management information includes, as file information in the secondary storage device 20, a directory structure and file name for identifying a file, a file type, a backup generation number, an archived flag, and a unique file ID for the archived file. And archive destination information such as an optical disk ID.

  As part of the secondary storage controller 21, the recovery manager 25 generates generation management information and archives from a group of files recorded separately on the hard disk device 22 and the write-once optical disk 1 in response to a request from the host computer 1. Extract files for recovery to any generation by referring to the management information.

FIG. 1 is a flowchart of the backup operation in the first embodiment.
The backup manager 13 creates a snapshot of the current file system of the primary storage 12 in S10.

  In S11, the current backup branches depending on whether it is a differential backup or a full backup. If the backup is a differential backup, in S12, a backup candidate flag in the file information is referenced to extract a file to be subjected to differential backup. In the case of full backup, the process of S12 is skipped.

  In S 13, generation management information is generated, output to the secondary storage device 20, and passed to the secondary storage controller 21. In step S14, the extracted differential backup target file is output to the secondary storage apparatus 20. In the secondary storage device 20, the received generation management information and the backup target file are recorded in the hard disk device 22.

  In S15, the archive manager 24 checks whether or not each newly recorded file on the hard disk device 22 is to be archived based on the file information in the generation management information received by the secondary storage controller 21 in S13. The file type is pre-registered data such as content created by the user, the number of times each file is played in a predetermined period is less than or equal to the predetermined number (for example, 0), and the archived flag is off Make the file an archive target.

  In S16, the process branches for each file according to the inspection result in S15. The archive candidate file is recorded on the write-once optical disc 1 by the optical disc device 23 in S17. For files that are not archive candidates, the process of S17 is skipped.

  Next, in S18, the process branches depending on whether or not the old generation backup is deleted. The number of backup generations to keep depends on the backup policy. For example, when 5 generations are held, the backup data of 5 generations before is deleted when a new backup is created. If there is no backup data to be deleted, the following processing from S19 to S22 is skipped.

  In S19, the archive manager 24 checks the backup data file to be deleted. Archive candidates are extracted from the backup data to be deleted based on the file information in the generation management information of the backup data and the archive management information. A file whose file type is data registered in advance such as content created by the user and whose archived flag is off is set as an archive candidate.

  In S20, the process branches for each file according to the inspection result in S19. The archive candidate file is recorded on the write-once optical disc 1 by the optical disc device 23 in S21. For files that are not archive candidates, the process of S21 is skipped.

  Thereafter, in S22, the old generation backup data is deleted from the hard disk device 22.

  In S23, the above-described archive management information is updated by reflecting the information recorded in the write-once optical disc 1 in S17 and S21. Further, the archive management information is passed to the host computer 10. Based on the received archive information, the host computer 10 updates archive destination information such as an archived flag in the file information, a unique file ID for the archived file, and an optical disk ID.

  According to this embodiment, necessary data can be archived appropriately and efficiently in cooperation with a backup operation for performing generation management.

  The configuration and operation of the hierarchical storage system as the second embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 3 is a block diagram of the hierarchical storage system in the second embodiment. The difference from the first embodiment is that in the secondary storage device 20, a storage for recording / reproducing information on a replaceable information recording medium is constituted by an optical disk changer 26.

  The optical disc changer 26 records and reproduces data on the write once optical disc 1 and the rewritable optical disc 2 mounted on the optical disc magazine 3. In this embodiment, as will be described later, the write-once optical disk 1 is used for archiving data, and the rewritable optical disk 2 is used for data backup. By using the write-once optical disc 1, tampering with archived data can be prevented. Further, the write-once optical disk 1 can be expected to be cheaper, record at a higher speed, and have a higher reproduction tolerance than the rewritable optical disk 2, so that an archive that needs to be expanded and stored for a long period of time corresponding to the cumulatively increasing data. Suitable for use. On the other hand, since the backup is assumed to be deleted after a certain period, the rewritable optical disk 2 that can be used repeatedly is suitable from the viewpoint of operation cost and resource saving. Other configurations are the same as those of the first embodiment, and the description thereof is omitted.

FIG. 4 is a flowchart of the backup operation in the second embodiment. The processing from S10 to S16 is the same as that in the first embodiment.
As a result of determining the file in S16, if it is an archive candidate, the file is recorded on the write-once optical disc 1 of the optical disc magazine 3 by the optical disc changer 26 in S24.

  If it is not an archive candidate, the file is recorded on the rewritable optical disc 2 of the optical disc magazine 3 by the optical disc changer 26 in S25. That is, all generations of backup data are recorded on a replaceable optical disk. In order to cope with a disaster (disaster recovery), data backup is preferably stored at a remote location, and this embodiment enables this.

  The processing from S18 to S20 is the same as that in the first embodiment. As a result of determining the file in S20, the archive candidate file is recorded on the write-once optical disc 1 of the optical disc magazine 3 by the optical disc changer 26 in S26. For files that are not archive candidates, the process of S26 is skipped.

  In S 27, the old generation backup data is deleted from the hard disk device 22. In the case of remote storage, although not limited to this, it is not necessary to store backups of all generations cumulatively. In the present embodiment, for example, it is assumed that a full backup is stored, and a differential backup is deleted when the number of generations to be stored is exceeded.

  The process of S23 is the same as that of the first embodiment.

  As described above, according to the present embodiment, similarly to the first embodiment, it is possible to appropriately and efficiently archive necessary data in cooperation with the backup operation for performing generation management. It can also support backup for disaster recovery.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of each embodiment.

  In addition, each of the above-described configurations may be configured such that some or all of them are configured by hardware, or are implemented by executing a program by a processor. Further, the control lines and information lines indicate what is considered necessary for the explanation, and not all the control lines and information lines on the product are necessarily shown. Actually, it may be considered that almost all the components are connected to each other.

DESCRIPTION OF SYMBOLS 1 ... Write-once optical disk, 2 ... Rewritable optical disk, 3 ... Optical disk magazine

Claims (6)

A hierarchical storage system having a first information recording device, a second information recording device, and a third information recording device that records and reproduces information on a replaceable information recording medium,
A backup control unit for transmitting data recorded in the first information recording device to the second information recording device;
A file information management unit for managing information on the type and operation of data recorded in the first information recording device;
An archive control unit for recording data recorded in the second information recording device in the third information recording device;
The archive control unit records a part of the data recorded in the second information recording device on the information recording medium by the third information recording device based on the information on the type and operation of the data. A tiered storage system characterized by   The archive control unit records the information on the information recording medium by the third information recording device when the data is data created by a user and the reference frequency in the first information recording device is a predetermined number of times or less. 2. The hierarchical storage system according to claim 1, wherein control is performed as follows.   The backup control unit performs backup generation management, and deletes the old generation backup data from the second information recording apparatus in the previous period, the user-created data among the old generation backup data, and the information 3. The hierarchical storage system according to claim 1, wherein data not recorded on a recording medium is recorded on the information recording medium by the third information recording apparatus.   4. The hierarchical storage system according to claim 2, wherein the third information recording device is an optical disc device, and the information recording medium is a write-once optical disc.   The archiving control unit is a rewritable optical disc in the third information recording device when the data is not data created by a user or when the reference frequency in the first information recording device is a predetermined number of times or more. 5. The hierarchical storage system according to claim 4, wherein the storage system is recorded in the storage system. A data archiving method for a hierarchical storage system, comprising: a first information recording device; a second information recording device; and a third information recording device that records and reproduces information on a replaceable information recording medium. ,
Transmitting data recorded in the first information recording device to the second information recording device;
Managing information on the type and operation of data recorded in the first information recording device;
A data archive in which a part of data recorded in the second information recording device is recorded on an information recording medium by the third information recording device based on the information on the type and operation of the data Method.

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