JP2018173915A - Backup system, storage device, data transfer method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a backup system that backs up data on a main site onto a remote site, and reduces the capacity of data to be transmitted and received between the main site and the remote site.SOLUTION: The backup system includes a master storage and a plurality of cloud storages. The master storage compresses data by one of a plurality of compression methods and stores the compressed data in a master volume. The plurality of cloud storages are installed at sites different from the master storage, and each has a backup volume. The master storage transmits the compressed data to one of the plurality of cloud storages. The cloud storage stores data acquired from the master storage in the backup volume.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a backup system, a storage device, a data transfer method, and a program.

  In a business system that includes a host computer and a storage device, a disaster recovery system may be constructed. In the disaster recovery system, backup is performed by transferring data at the main site to the remote site, and in the event of a disaster at the main site, the data is acquired from the remote site and the work is performed. For example, Patent Document 1 describes that when a failure of a master server occurs, another slave server takes as short an interruption time as possible and appropriately takes over the service of the master server.

  In data exchange between devices, data is transferred or compressed after the data is compressed for the purpose of suppressing the data transfer amount and the data storage amount. For example, in Patent Document 2, before data is transferred to the shared memory, the data is compressed locally. It is described that the memory stores the compressed data in the same arrangement as when the data is not compressed. Further, in Patent Document 3, when a desired compression rate cannot be obtained as a result of compression at a certain compression level, the compression level is increased and recompression is performed by using a compression parameter at that level. It is described that a high compression ratio can be obtained.

  On the other hand, in recent years, due to the development of network technology and the like, there is an environment where inexpensive cloud servers and cloud storage can be used. Therefore, in a disaster recovery system, such external server storage (cloud server, cloud storage) may be used to perform data backup operation or recovery in the event of a disaster (disaster recovery operation).

JP 2000-163300 A JP 2010-92499 A JP 2000-227844 A

  Each disclosure of the above prior art document is incorporated herein by reference. The following analysis was made by the present inventors.

  As described above, there is a disaster countermeasure operation in which data in the storage device at the main site is transferred to an external cloud server or cloud storage, and operations can be continued when the main site is damaged. In such disaster countermeasure operation, since business data is transferred to an external site, it is desired to reduce the data transfer amount and reduce the network load. It is also necessary to reduce the capacity of the cloud storage used.

  As described above, data is compressed in order to suppress data transfer between devices, but this method can be used on the premise that the same compression method is supported between devices that transmit and receive data. It is. In other words, in order to reduce the amount of data transferred for disaster countermeasure operation, it is conceivable that compressed data is sent from the main site to storage at a remote site connected via a network, and the compressed data is expanded at the remote site. However, such an operation is not applicable to cloud storage that requires storage devices having the same function at the main site and the remote site and may not have the same function.

  The present invention provides a backup system, a data transfer method, and a program that contribute to reducing the data capacity transmitted and received between the main site and the remote site in a backup system that backs up data at the main site to the remote site. Objective.

  According to a first aspect of the present invention, a master storage that compresses data by any one of a plurality of compression methods and stores the compressed data in a master volume, and is installed at a site different from the master storage A plurality of cloud storages each having a backup volume, the master storage sends the compressed data to any one of the plurality of cloud storages, the cloud storage, A backup system is provided that stores data acquired from the master storage in the backup volume.

  According to the second aspect of the present invention, the storage device is connected to a plurality of cloud storages and installed at a site different from the plurality of cloud storages, and the data is compressed by any one of a plurality of compression methods. And a data output unit that transmits the compressed data to any one of the plurality of cloud storages.

  According to a third aspect of the present invention, the master storage that compresses data by any one of a plurality of compression methods and stores the compressed data in a master volume, and is installed at a site different from the master storage A plurality of cloud storages each having a backup volume, and transmitting the compressed data to any one of the plurality of cloud storages, and obtaining from the master storage Storing the processed data in the backup volume.

According to the fourth aspect of the present invention, any of a plurality of compression methods can be used to store data in a computer connected to a plurality of cloud storages and installed in a storage device installed at a site different from the plurality of cloud storages. And a program for executing the process of transmitting the compressed data to any one of the plurality of cloud storages.
This program can be recorded on a computer-readable storage medium. The storage medium may be non-transient such as a semiconductor memory, a hard disk, a magnetic recording medium, an optical recording medium, or the like. The present invention can also be embodied as a computer program product.

  According to each aspect of the present invention, in a backup system that backs up data at a main site to a remote site, the backup system, a data transfer method, and a program that contribute to reducing the data capacity transmitted and received between the main site and the remote site Is provided.

It is a figure for demonstrating the outline | summary of one Embodiment. It is a figure which shows an example of schematic structure of the backup system which concerns on 1st Embodiment. It is a figure which shows an example of a compression management table. It is a figure which shows an example of an address management table. It is a figure which shows an example of a storage location management table. It is a flowchart which shows an example of operation | movement of a 1st compression part. It is a flowchart which shows an example of operation | movement of a 2nd compression part. It is a flowchart which shows an example of operation | movement of a data output part. It is a flowchart which shows an example of operation | movement of a remote compression expansion | deployment part. It is a flowchart which shows an example of operation | movement of a remote access part.

  First, an outline of one embodiment will be described. Note that the reference numerals of the drawings attached to the outline are attached to the respective elements for convenience as an example for facilitating understanding, and the description of the outline is not intended to be any limitation. In addition, the connection lines between the blocks in each drawing include both bidirectional and unidirectional directions. The unidirectional arrow schematically shows the main signal (data) flow and does not exclude bidirectionality.

  The backup system according to an embodiment includes a master storage 101 and a plurality of cloud storages 102 (see FIG. 1). The master storage 101 compresses data by any one of a plurality of compression methods, and stores the compressed data in the master volume. The plurality of cloud storages 102 are installed at a different site from the master storage 101, and each has a backup volume. The master storage 101 transmits the compressed data to any one of the plurality of cloud storages 102. The cloud storage 102 stores the data acquired from the master storage 101 in a backup volume.

  As described above, the master storage 101 of the backup system according to the embodiment compresses data using different compression methods. At that time, the master storage 101 compresses the data using a compression method having a high compression rate (for example, a post-process compression method) as necessary, and transmits the data to the cloud storage 102, so that the master storage (main site) Can reduce the amount of data sent to cloud storage (remote site).

  Hereinafter, specific embodiments will be described in more detail with reference to the drawings. In addition, in each embodiment, the same code | symbol is attached | subjected to the same component and the description is abbreviate | omitted.

[First Embodiment]
The first embodiment will be described in more detail with reference to the drawings.

  FIG. 2 is a diagram illustrating an example of a schematic configuration of the backup system according to the first embodiment. Referring to FIG. 2, the backup system includes a main site and a remote site. The backup system shown in FIG. 2 is a system that transfers master storage data at a main site to a cloud storage at a remote site connected via a network so that it can be read and written from a cloud server for disaster countermeasure operation.

  In the backup system shown in FIG. 2, the master storage 20 is arranged at the main site, and the cloud storages 40-1 and 40-2 are arranged at the remote sites at remote locations. In the backup system, the data stored in the master volume on the master storage 20 is copied (copied) to the cloud storage 40 to prevent data loss when the main site is damaged, for example.

  The main site includes a main server 10 and a master storage 20 connected to the main server 10 via a network.

  The main server 10 is a device that accesses data stored in the master storage 20 in response to a request from a host terminal (not shown) and provides services to the host terminal.

  The master storage 20 forms a pool that is a virtual storage area from a set of magnetic disks (HDD; Hard Disk Drive) and semiconductor disks (SSD: Solid State Drive), cuts out a plurality of logical disks from the pool, 10 is a storage device that can be read from and written to.

  The remote site (site different from the main site) includes a plurality of cloud servers 30-1 and 30-2 and a plurality of cloud storages 40-1 and 40-2 connected to these cloud servers via a network. It is. The cloud server 30-1 is configured to be accessible to the cloud storage 40-1, and the cloud server 30-2 is configured to be accessible to the cloud storage 40-2.

  2 shows two sets of cloud servers and cloud storages, the number of cloud servers and the like arranged at the remote site is not limited to two. It is sufficient that two or more cloud servers or the like are installed at the remote site. Further, each device such as a cloud server does not need to be installed at the same remote site.

  In the following description, when there is no particular reason for distinguishing between the cloud servers 30-1 and 30-2, it is simply expressed as “cloud server 30”. Similarly, other configurations are represented by the numbers described before the hyphen (-) as a representative.

  The master storage 20 at the main site includes a master volume 21 that can be accessed (read / written) from the main server 10, a controller 22, and a storage medium that stores table information. In FIG. 2, a compression management table 23 is shown as table information.

  The controller 22 is a module (means) that controls the entire master storage 20. The controller 22 performs access control for the master volume 21. Further, the controller 22 controls a NIC (Network Interface Card) that is a communication interface built in the master storage 20 to realize mutual communication with an external device.

  The controller 22 includes three processing modules: a first compression unit 201, a second compression unit 202, and a data output unit 203.

  The first compression unit 201 is a means for performing inline compression that has a low data amount reduction effect but has a high compression processing speed among various existing data compression techniques. The first compression unit 201 is an in-disk compression unit that compresses and stores data in a certain unit (block) written from the main server 10 when writing to the master volume 21.

  The second compression unit 202 is a unit that performs post-process compression that has a large data amount reduction effect but has a slow compression processing speed. The second compression unit 202 is data compressed by the first compression unit 201, and is an inter-disk compression unit that further compresses data from a set of blocks between a plurality of disks (logical volumes). As described above, the compression method employed by the second compression unit 202 is a method for further compressing (recompressing) a plurality of data compressed by the first compression unit 201. An arbitrary algorithm can be used as the compression algorithm by the first compression unit 201 and the second compression unit 202. For example, the LZ method or the zlib method can be used.

  In the master storage 20, when the data acquired from the main server 10 can be compressed, either one or both of the two compression methods are used. Note that data compression may not be possible depending on data characteristics (for example, size). In such a case, the controller 22 writes the uncompressed data as it is in the master volume 21. In the following description, the compression method by the first compression unit 201 is expressed as compression method 1, and the compression method by the second compression unit 202 is expressed as compression method 2, respectively.

  As described above, the first compression unit 201 compresses data by the compression method 1. That is, in the main site inline compression method, a set of a plurality of blocks in the same volume written in a short time is compressed as a compression target. Further, the second compression unit 202 compresses data from the data of the compression method 1 across the plurality of disks to the compression method 2. In other words, in the post-process compression method, a set of blocks extending over a plurality of volumes is set as a compression target, and further compressed as compared with the inline method. Reduce capacity.

  The data output unit 203 is means for asynchronously transmitting the data compressed by the first compression unit 201 and the second compression unit 202 or uncompressed data (uncompressed data) to the cloud storage 40. The data output unit 203 reads data from the master volume 21 and stores the data in the backup volume 41 of the cloud storage 40 as backup data. At that time, the data output unit 203 distributes and outputs the data (compressed data, uncompressed data) stored in the master volume 21 to the plurality of cloud storages 40 according to the information stored in the compression management table 23.

  In addition, the data output unit 203 transmits information regarding the location of the backup data to all the cloud storages 40. The information on the location of the backup data includes information on the compression method (including uncompressed) when the master storage 20 compresses the data, information on the address of the transmitted compressed data (including uncompressed data), and transmission And information on the storage location of the compressed data.

  The compression management table 23 is table information indicating the compression status of data stored in the master volume 21. The compression management table 23 manages the mapping information of the master volume 21, and records the compression status of each data and the data transfer destination.

  FIG. 3 is a diagram illustrating an example of the compression management table. The area of the master volume 21 is divided in units of predetermined blocks, and data is managed in the compression management table 23 in units of the blocks. Referring to FIG. 3, the address field indicates address information obtained by dividing the master volume 21 into predetermined block units.

  The controller 22 writes the data (original data) acquired from the main server 10 as the original data (writes uncompressed data) or writes compressed data. Further, the controller 22 compresses the data using the compression method 1 and the compression method 2 separately. At that time, the controller 22 (the first compression unit 201 and the second compression unit 202) sets the compression status (non-compression, compression method 1, compression method 2) of the data written in the master volume 21 in the compression management table 23. Write to the corresponding compression status field.

  Further, when the controller 22 writes the data compression status in the compression management table 23, the controller 22 writes the identification information of the cloud storage 40 that is the output destination of the data (backup data transfer destination) in the corresponding transfer destination field of each data. .

  In FIG. 3, the code shown in FIG. 2 is used as the identifier of the cloud storage 40. However, the IP (Internet Protocol) address or the like of each cloud storage 40 may actually be used.

  In the first embodiment, the controller 22 writes information such that uncompressed data and data related to the compression method 1 are transferred to the cloud storage 40-1.

  On the other hand, the controller 22 writes information related to the data related to the compression method 2 so as to be transferred to either the cloud storage 40-1 or 40-2. For example, referring to FIG. 3, the uncompressed data in the first and second rows and the data related to the compression method 1 are scheduled to be transferred to the cloud storage 40-1, but the third and fourth rows. It is unknown whether the data related to the second compression method 2 is transferred to the cloud storage 40-1 or 40-2.

  That is, in the case of non-compressed data or data related to the compression method 1, the backup destination of the data is fixed to one cloud storage 40, but in the case of data related to the compression method 2, the transfer destination candidate of the data is Multiple. This is because the compressed data by the compression method 2 is data associated with a plurality of disks (because data straddling a plurality of storage media is used), and therefore the transfer destination cannot be arbitrarily determined.

  Returning to FIG. 2, the cloud server 30 is a device on the remote site side corresponding to the main server 10.

  When the main site is damaged, the cloud server 30 provides the host terminal (not shown) with the service provided by the main server 10 instead of the main server 10. Note that the host terminal can receive service provision equivalent to the service provided by the main server 10 regardless of which of the cloud servers 30-1 and 30-2 is accessed.

  The cloud server 30 acquires data (backup data of the master storage 20) from the cloud storage 40, and provides a service using the acquired data.

  The cloud server 30 includes a controller 31. The controller 31 is a module (means) that controls the entire cloud server 30. The controller 31 controls a NIC (Network Interface Card) that is a communication interface built in the cloud server 30 to realize mutual communication with an external device.

  The controller 31 includes a remote compression / decompression unit 301 and a remote access unit 302.

  The remote compression / decompression unit 301 is a unit that decompresses the compressed data and enables reading / writing of data stored in the volume of the cloud storage 40 from the cloud server 30.

  Specifically, the remote compression / decompression unit 301 decompresses the compressed data stored in the cloud storage 40 and acquires original data. Alternatively, the remote compression / decompression unit 301 compresses the original data acquired from the cloud server 30. The compressed original data is written to the backup volume 41 by the remote access unit 302.

  The remote access unit 302 is a means for accessing data stored in the cloud storage 40 in response to a request from the remote compression / decompression unit 301 or a request from the remote access unit 302 incorporated in another cloud server 30. is there. When the necessary data does not exist in the cloud storage 40 corresponding to the own device (cloud server 30), the remote access unit 302 applies to the cloud storage 40 corresponding to another cloud server 30 that holds the necessary data. Request data output (data acquisition) and acquire necessary data. For example, when the cloud server 30-1 requests data that is not stored in the cloud storage 40-1 from the host terminal, the cloud corresponding to the cloud storage (for example, the cloud storage 40-2) that stores the data The server 30-2 is requested to acquire the data.

  The cloud server 30-1 and the cloud server 30-2 can have the same configuration. The cloud server 30 includes a storage medium for storing data and the like, but these are not shown in FIG.

  The cloud storage 40 is a device that holds backup data of the master storage 20.

  The cloud storage 40 includes a backup volume 41, a controller 42, and a storage medium that stores table information. In FIG. 2, an address management table 43 and a storage location management table 44 are shown as table information.

  The backup volume 41 holds backup data of the master volume 21.

  The controller 42 is a module (means) that controls the entire cloud storage 40. The controller 42 controls a NIC (Network Interface Card) which is a communication interface built in the cloud storage 40 and realizes mutual communication with an external device. The controller 42 includes an access control unit 401 and a table management unit 402.

  The access control unit 401 is a means for processing requests from the master storage 20 and the cloud server 30. Specifically, when the access control unit 401 acquires backup data from the master storage 20, the access control unit 401 stores the data in the backup volume 41 of its own device. At that time, the access control unit 401 updates the address management table 43.

  FIG. 4 is a diagram illustrating an example of the address management table 43. As described above, data is transmitted from the master storage 20. Since the data includes address information in the master volume 21, the address (master data address) in the master volume 21 is managed by the address management table 43 in association with the data storage destination address of the backup volume 41. The By referring to the address management table 43, the access control unit 401 can know at which address the backup data to be accessed is stored.

  4A shows an example of the address management table 43-1 in the cloud storage 40-1, and FIG. 4B shows an example of the address management table 43-2 in the cloud storage 40-2. .

  Further, the access control unit 401 processes an access request (data write / read) from the cloud server 30 corresponding to the own device. For example, the access control unit 401 reads the data specified by the address information (that is, the master data address) of the backup data to be read from the backup volume 41 and outputs it to the cloud server 30.

  The table management unit 402 is means for acquiring information related to the location of backup data from the master storage 20 and updating the storage location management table 44 with the acquired information.

  The storage location management table 44 is table information for managing the address of the backup data (master data address), the compression status of the relevant data, and the storage location of the relevant data.

  FIG. 5 is a diagram illustrating an example of the storage location management table 44. Referring to FIG. 5, the compression status field stores the compression status (non-compression, compression method 1, compression method 2) of each data (block).

  The storage destination field indicates the storage destination of each data (block). For example, referring to FIG. 5, data stored at the address “100” of the master volume 21 (backup data corresponding to the address) is stored in the cloud storage 40-1 without being compressed.

  On the other hand, the data stored at the address “102” is compressed by the compression method 2 and indicates that the compressed data is stored in the cloud storage 40-2.

  As described above, since the information regarding the location of the same backup data is transmitted from the master storage 20 to all the cloud storages 40, the contents of the storage location management table 44 constructed in each cloud storage 40 are the same.

  Subsequently, the operation of each device constituting the first embodiment will be described with reference to the drawings.

  FIG. 6 is a flowchart illustrating an example of the operation of the first compression unit 201.

  The first compression unit 201 operates when write data is received from the main server 10. The first compression unit 201 writes original data (data before compression) into a predetermined area (predetermined volume) of the master volume 21 (step S01).

  After that, the first compression unit 201 specifies a location to be compressed from the block set in the storage medium written in step S01 (step S02). That is, the first compression unit 201 identifies a block in which data is written in step S01 among a plurality of blocks constituting the storage medium in which the data is written.

  Thereafter, the first compression unit 201 compresses the data in the identified block and updates the compression management table 23 (step S03). The first compression unit 201 compresses the data at a timing (inline) when the original data is received, and stores the compressed data in a predetermined block of the master volume 21.

  FIG. 7 is a flowchart illustrating an example of the operation of the second compression unit 202.

  The second compression unit 202 periodically operates to create compressed data by the compression method 2.

  The second compression unit 202 collates the relevance between the data stored in the plurality of volumes for the data compressed by the first compression unit 201 (data by the compression method 1) (step S11).

  Based on the collation, it is determined whether there is data that can further increase the compression rate of the compression method 1. For example, the above determination is performed depending on whether or not there is an area (area having the same binary data) common to data (blocks) compressed by the compression method 1 in a predetermined ratio or more.

  When data having a predetermined relationship (a plurality of data by the compression method 1) is found, the second compression unit 202 specifies addresses of the plurality of data (step S12).

  The second compression unit 202 compresses the data by applying the compression method 2 to the plurality of identified data, and updates the compression management table 23. At that time, the second compression unit 202 sets either the cloud storage 40-1 or 40-2 in the output destination field of the compression management table. The second compression unit 202 deletes the compressed data before re-compression (a plurality of data by the compression method 1) (step S13). That is, if the second compression unit 202 further compresses the plurality of data by the compression method 1 and determines that the data amount can be reduced, the second compression unit 202 further recompresses the plurality of data.

  FIG. 8 is a flowchart showing an example of the operation of the data output unit 203.

  The data output unit 203 operates periodically and outputs the data stored in the block of the master volume 21 to the cloud storage 40 that is the backup destination asynchronously with writing to the master volume 21. The data is transmitted in units of blocks. The data output unit 203 selects one of the plurality of cloud storages 40 according to the type of data (non-compression, compression method 1, compression method 2) and transmits the data.

  The data output unit 203 refers to the compression management table 23 and confirms the block (transfer target block) of the transfer target master volume 21 (step S21).

  Next, the data output unit 203 determines the cloud storage 40 to be transferred (step S22). Specifically, the data output unit 203 refers to the output destination field of the compression management table 23 and determines the data output destination. For example, referring to the compression management table 23 shown in FIG. 3, the output destination of data by the non-compression, compression method 1 is limited to one of the cloud storage 40-1. On the other hand, either the cloud storage 40-1 or the cloud storage 40-2 is the output destination for the data by the compression method 2. That is, for the data compressed by the compression method 2, the data output unit 203 selects one of the cloud storage 40-1 and the cloud storage 40-2, and uses the selected cloud storage 40 as the data transmission destination. To decide. It is desirable that the determination be made so that no extreme bias or the like occurs.

  The data output unit 203 outputs data to the previously determined cloud storage 40 (step S23).

  Thereafter, the data output unit 203 transmits information regarding the location of the backup data to all the cloud storages 40 (step S24). Specifically, the data output unit 203 transmits the address information of the output data (block), the compression status of the data, and information regarding the output destination (data storage destination) of the data to all the cloud storages 40. To do. For example, referring to FIG. 3, when the data output unit 203 transmits the data stored at the address “100” to the cloud storage 40-1, the address information “100” and the data compression status “uncompressed”. , Information including “cloud storage 40-1” as the output destination is transmitted to the cloud storages 40-1 and 40-2.

  Alternatively, when the data output unit 203 transmits the data stored at the address “102” to the cloud storage 40-2, the address information “102”, the data compression status “compression method 2”, and the output destination “ Information including “cloud storage 40-2” is transmitted to the cloud storages 40-1 and 40-2.

  The table management unit 402 of the cloud storage 40 that has received the information updates the storage location management table 44.

  FIG. 9 is a flowchart illustrating an example of the operation of the remote compression / decompression unit 301.

  The remote compression / decompression unit 301 operates on the cloud server 30 and operates when accessing the backup volume 41 of the cloud storage 40 from the cloud server 30.

  The remote compression / decompression unit 301 specifies a block to be accessed (step S31). For example, the remote compression / decompression unit 301 identifies backup data that needs to be acquired based on an access request from a host terminal connected to the cloud server 30.

  Thereafter, the remote compression / decompression unit 301 designates necessary backup data by the address information (master data address) of the identified backup data, and requests the remote access unit 302 to acquire the data (step S32).

  The remote access unit 302 acquires the requested data from the cloud storage 40 and delivers the acquired data to the remote compression / decompression unit 301.

  Thereafter, if the acquired data is compressed, the remote compression / decompression unit 301 expands the compressed data into readable / writable original data (step S33). The developed original data is used for a service provided to the host terminal.

  FIG. 10 is a flowchart illustrating an example of the operation of the remote access unit 302.

  The remote access unit 302 operates in response to a request from the remote compression / decompression unit 301 in its own device or a request from the remote access unit 302 in another cloud server 30. The request includes address information (master data address) of data to be acquired.

  FIG. 10A shows an example of the operation of the remote access unit 302 when it is activated in response to a request from the remote compression / decompression unit 301 in its own apparatus.

  The remote access unit 302 refers to the storage location management table 44 via the controller 42 of the cloud storage 40 corresponding to the own device (cloud server 30), and identifies the cloud storage 40 in which the target block exists (step S41).

  Thereafter, the remote access unit 302 determines whether the block (backup data) to be accessed exists in the cloud storage 40 corresponding to the own device (step S42). For example, if the target block is non-compressed data or compressed data by the compression method 1, the block exists in the backup volume 41-1 of the cloud storage 40-1. On the other hand, in the case of compressed data by the compression method 2, it is certain whether the block exists in the cloud storage 40 corresponding to the own device (cloud server 30) or in the cloud storage 40 not compatible with the own device. Absent.

  Therefore, the remote access unit 302 refers to the storage location management table 44 and checks whether necessary data exists in the cloud storage 40 corresponding to the own device or in another cloud storage 40. In the example of FIG. 5, the remote access unit 302 includes the compressed data in the compression method 2 at the address “103” in the cloud storage 40-1 and the compressed data in the compression method 2 at the address “102” in the cloud storage 40-2. Grasp that exists.

  When the data exists in the cloud storage 40 corresponding to the own device (step S42, Yes branch), the remote access unit 302 specifies the address information of the data to be acquired and corresponds to the acquisition of the data to the own device. A request is made to the cloud storage 40 (step S43).

  Upon receiving the request, the controller 42 of the cloud storage 40 reads the backup data corresponding to the specified address information (master data address) from the backup volume 41 with reference to the address management table 43. The read data is transmitted to the remote access unit 302, and the remote access unit 302 acquires the data requested from the remote compression / decompression unit 301.

  When the data does not exist in the cloud storage 40 corresponding to its own device (step S42, No branch), the remote access unit 302 sends the address information of the data to be acquired to the remote access unit 302 of the other cloud server 30. Is requested to acquire the data (step S44).

  Upon receiving the request, the remote access unit 302 acquires data from the cloud storage 40 (backup volume 41) and transmits the data to the requesting remote access unit 302.

  The remote access unit 302 provides (outputs) the acquired data to the remote compression / decompression unit 301 (step S45).

  FIG. 10B shows an example of the operation of the remote access unit 302 when activated by a request from the remote access unit 302 of another cloud server 30.

  The remote access unit 302 receives a data acquisition request from the remote access unit 302 of the other cloud server 30 (step S51).

  Thereafter, the remote access unit 302 refers to the storage location management table 44 of the cloud storage 40 corresponding to the own device, and confirms that the requested data exists in the cloud storage 40 corresponding to the own device (step S52). .

  Thereafter, the remote access unit 302 acquires the requested data from the cloud storage 40 corresponding to the own device (step S53).

  The remote access unit 302 outputs the acquired data to the request source (remote access unit 302 of the other cloud server 30) that transmitted the data acquisition request (step S54).

  The controller included in the master storage 20 or the like uses the hardware of a computer (for example, a CPU (Central Processing Unit) or the like) installed in the master storage 20 or the like to process the processing module of each controller described above. It can also be realized by a computer program that executes

  As described above, in the backup system according to the first embodiment, the first compression unit 201 (in-disk compression unit) compresses data by the compression method 1 when writing data. Further, the second compression unit 202 (inter-disk compression means) compresses data over a plurality of disks compressed by the compression method 1 by the compression method 2 having a higher compression rate. The data output in this way is asynchronously transferred by the data output unit 203 to the external cloud storage 40. When the target data is the compression method 1, the data is fixedly transmitted to the cloud storage 40, and the data of the compression method 2 is output to any one of the cloud storages 40. Furthermore, when the compressed data cannot be expanded at the remote site (cloud server 30, cloud storage 40) (when the original data cannot be restored), the original data is referred to the data of other cloud storage 40. Restore. Further, the master storage 20 transfers the mapping information between the original data and the compressed data to the management data area of the cloud storage 40 that is all output destinations. For example, when the remote compression / decompression unit 301-1 on the cloud server 30-1 reads / writes the backup volume 41-1 constructed on the cloud storage 40-1 from the cloud server 30-1, the data of the compression method 1 If so, the data can be converted to the original data. On the other hand, in the case of data of the compression method 2, if data exists on the target cloud storage 40-1, it can be converted to original data. If it does not exist, the remote access unit 302-1 acquires the data. Request. In response to a request from the remote compression / decompression unit 301-1, the remote access unit 302-1 confirms whether the requested data exists on the other cloud storage 40-2, and acquires the data.

  With the above configuration, it is possible to provide a backup system that enables disaster countermeasure operation using an inexpensive cloud cloud server and cloud storage at the remote site without installing a storage system having the same function as the main site at the remote site. In other words, by combining a plurality of compression methods, it is possible to reduce the amount of data stored in the master storage 20 at the main site and to reduce the amount of data transferred from the main site to the remote site.

  The configuration, operation, and the like of the backup system described in the above embodiment are merely examples, and are not intended to limit the system configuration. For example, in the above embodiment, the compression method 1 data is fixedly transmitted to the cloud storage 40-1. However, the compression method 2 data is fixedly transmitted to the cloud storage 40-2, for example. May be. In this case, the cloud storage 40-1 stores uncompressed data and compression method 1 data, and the cloud storage 40-2 stores uncompressed data, compression method 1 data, and compression method 2 data. become. In addition, a situation is considered in which the remote compression / decompression unit 301-1 is compatible only with the compression method 1, and the remote compression / decompression unit 301-2 is compatible with the compression methods 1 and 2. When the compression method 2 data is required, the remote compression / decompression unit 301-1 requests the cloud server 30-2 to acquire the compression method 2 data stored in the cloud storage 40-2. Upon receiving the request, the remote compression / decompression unit 301-2 of the cloud server 30-2 acquires the data of the compression method 2 from the backup volume 41-2, decompresses the data by the compression method 2, and then converts the original data to the cloud server. To 30-1. With such a correspondence, the remote compression / decompression unit 301-1 can obtain original data compressed by the compression method 2 not supported by itself.

A part or all of the above embodiments can be described as in the following supplementary notes, but is not limited thereto.
[Appendix 1]
This is the same as the backup system according to the first aspect described above.
[Appendix 2]
A plurality of cloud servers corresponding to each of the plurality of cloud storages;
The first cloud server out of the plurality of cloud servers, when the necessary data is not stored in the cloud storage corresponding to its own device, the acquisition of the necessary data among the plurality of cloud servers Request to a second cloud server different from the first cloud server,
The backup system according to appendix 1, wherein the second cloud server acquires the requested data from the cloud storage corresponding to its own device, and outputs the acquired data to the first cloud server.
[Appendix 3]
The master storage is information relating to the location of backup data, including information relating to a compression method when data is compressed, information relating to an address of the transmitted compressed data, and information relating to a storage destination of the transmitted compressed data. The backup system according to appendix 2, wherein: is transmitted to the plurality of cloud storages.
[Appendix 4]
The backup system according to appendix 3, wherein the cloud server determines whether or not the necessary data exists in the cloud storage corresponding to the own device based on information on the location of the backup data.
[Appendix 5]
The backup system according to any one of appendices 2 to 4, wherein when the data acquired from the cloud storage is compressed, the cloud server expands the acquired data and acquires original data.
[Appendix 6]
The backup system according to any one of appendices 1 to 5, wherein the master storage compresses data by an inline method.
[Appendix 7]
The backup system according to any one of appendices 1 to 6, wherein the master storage compresses data by a post-process method.
[Appendix 8]
The storage device according to the second aspect described above.
[Appendix 9]
This is as the data transfer method according to the third aspect described above.
[Appendix 10]
It is as the program which concerns on the above-mentioned 4th viewpoint.
Note that the forms of Supplementary Note 8 to Supplementary Note 10 can be expanded to the forms of Supplementary Note 2 to Supplementary Note 7 as with the form of Supplementary Note 1.

  Each disclosure of the cited patent documents and the like cited above is incorporated herein by reference. Within the scope of the entire disclosure (including claims) of the present invention, the embodiments and examples can be changed and adjusted based on the basic technical concept. In addition, various combinations or selections of various disclosed elements (including each element in each claim, each element in each embodiment or example, each element in each drawing, etc.) within the scope of the entire disclosure of the present invention. Is possible. That is, the present invention of course includes various variations and modifications that could be made by those skilled in the art according to the entire disclosure including the claims and the technical idea. In particular, with respect to the numerical ranges described in this document, any numerical value or small range included in the range should be construed as being specifically described even if there is no specific description.

10 Main server 20, 101 Master storage 21 Master volume 22, 31, 31-1, 31-2, 42, 42-1, 42-2 Controller 23 Compression management table 30, 30-1, 30-2 Cloud server 40, 40-1, 40-2, 102 Cloud storage 41, 41-1, 41-2 Backup volume 43, 43-1, 43-2 Address management table 44, 44-1, 44-2 Storage destination management table 201 1st Compression unit 202 Second compression unit 203 Data output unit 301, 301-1, 301-2 Remote compression / decompression unit 302, 302-1 and 302-2

Claims (10)

Master storage for compressing data by one of a plurality of compression methods and storing the compressed data in a master volume;
A plurality of cloud storages installed at different sites from the master storage, each having a backup volume;
Including
The master storage sends the compressed data to any one of the plurality of cloud storages,
The cloud storage is a backup system that stores data acquired from the master storage in the backup volume. A plurality of cloud servers corresponding to each of the plurality of cloud storages;
The first cloud server out of the plurality of cloud servers, when the necessary data is not stored in the cloud storage corresponding to its own device, the acquisition of the necessary data among the plurality of cloud servers Request to a second cloud server different from the first cloud server,
The backup system according to claim 1, wherein the second cloud server acquires the requested data from the cloud storage corresponding to its own device, and outputs the acquired data to the first cloud server.   The master storage is information relating to the location of backup data, including information relating to a compression method when data is compressed, information relating to an address of the transmitted compressed data, and information relating to a storage destination of the transmitted compressed data. Is transmitted to the plurality of cloud storages.   The backup system according to claim 3, wherein the cloud server determines whether the necessary data exists in the cloud storage corresponding to the own device based on information regarding the location of the backup data.   The backup system according to any one of claims 2 to 4, wherein, when the data acquired from the cloud storage is compressed, the cloud server expands the acquired data and acquires original data. .   The backup system according to claim 1, wherein the master storage compresses data by an inline method.   The backup system according to any one of claims 1 to 6, wherein the master storage compresses data by a post-process method. A storage device connected to a plurality of cloud storages and installed at a different site from the plurality of cloud storages,
A compression unit that compresses data using one of a plurality of compression methods;
A data output unit that transmits the compressed data to any one of the plurality of cloud storages; and
A storage apparatus. Master storage for compressing data by one of a plurality of compression methods and storing the compressed data in a master volume;
A plurality of cloud storages installed at different sites from the master storage, each having a backup volume;
In the backup system including
Transmitting the compressed data to any one of the plurality of cloud storages;
Storing the data acquired from the master storage in the backup volume; and
Including data transfer method. A computer connected to a plurality of cloud storages and installed in a storage device installed at a site different from the plurality of cloud storages.
A process of compressing data with one of a plurality of compression methods;
A process of transmitting the compressed data to any one of the plurality of cloud storages;
A program that executes

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