Snapshot acquisition method, storage system and disk apparatus

• US 7,120,768 B2
• Filed: 10/24/2002
• Issued: 10/10/2006
• Est. Priority Date: 03/22/2002
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Sonoda, Koji, Mizuno, Yoichi, Kitamura, Manabu, Matsunami, Naoto, Kishima, Shinichi
• Primary Examiner(s): GOODARZI, NASSER MOAZZAMI
• Application Number:
  US10/279,581
• Publication Number:
  US 20030229651A1
• Time in Patent Office: 1,447 Days
• Field of Search: 711/162, 711/161, 707203-204
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A network attached storage (NAS) system includes a disk array unit equipped with a copy device that copies data, and a NAS processing unit that provides file service via a network and is connected via a communication path to the disk array unit. The NAS processing unit is equipped with a snapshot management device that manages snapshots. The snapshot management device of the NAS processing unit designates a physical block to be copied as a snapshot. The copy device on the disk array unit copies the designated physical block within the disk array unit to create a snapshot and stores the snapshot in a separated region. The snapshot management device of the NAS processing unit manages meta data of the snapshot data in a manner accessible by the user depending on requirements.

Claims

1. A snapshot acquisition method in a storage system including a storage apparatus for storing data and a NAS processing apparatus that provides file service via a communication path and is connected to the storage apparatus, the snapshot acquisition method comprising:

managing snapshots by the NAS processing apparatus;

upon receiving at the NAS processing apparatus a data renewal request to renew data targeted for snapshot, issuing from the NAS processing apparatus a data copy instruction to a copy apparatus of the storage apparatus to copy the data targeted for snapshot; and

preserving by the copy apparatus the data in a separate region of the storage apparatus based on the received data copy instruction sent from the NAS processing apparatus;

wherein the preserving step is performed by the copy apparatus of the storage apparatus.

2. A snapshot acquisition method according to claim 1, wherein the communication path is a network.

3. A snapshot acquisition method according to claim 1, wherein the data includes a plurality of files, and each of the files includes at least one block, wherein the data renewal request is an instruction to renew said at least one block in one of the files, wherein the storage apparatus copies said at least one block in the separate region.

4. A snapshot acquisition method according to claim 1, wherein the data copy instruction designates a physical address of the data, a block length of the data, and a physical address at a copy destination where the data is copied.

5. A snapshot acquisition method according to claim 3, wherein the data copy instruction designates a physical address of said at least one block, a block length of said at least one block, and a physical address at a copy destination where said at least one block is copied.

6. A storage system comprising:

a storage apparatus for storing data, the storage apparatus including a copy device that copies data; and

a NAS processing apparatus that provides file service via a communication path and is connected to the storage apparatus, the NAS processing apparatus including a snapshot management device that manages snapshots,

wherein, upon receiving a data renewal request to renew data targeted for snapshot, the snapshot management device issues a data copy instruction to the copy device of the storage apparatus to copy the data targeted for snapshot; and

the copy device receives the data copy instruction from the snapshot management device and copies the data based on the received data copy instruction, and preserves the data in a separate region of the storage apparatus.

7. A storage system according to claim 6, wherein the communication path is a network.

8. A storage system according to claim 6, wherein the data includes a plurality of files, and each of the files includes at least one block, wherein the data renewal request is an instruction to renew the at least one block in one of the files, wherein the storage apparatus copies said at least one block in the separate region.

9. A storage system according to claim 6, wherein the data copy instruction designates a physical address of the data, a block length of the data, and a physical address at a copy destination where the data is copied.

10. A storage system according to claim 8, wherein the data copy instruction designates a physical address of said at least one block, a block length of said at least one block, and a physical address at a copy destination where said at least one block is copied.

11. A snapshot acquisition method in a storage system including a storage apparatus for storing data and a NAS processing apparatus that provides file service via a communication path and is connected to the storage apparatus, the snapshot acquisition method comprising:

managing snapshots by the NAS processing apparatus;

issuing from the NAS processing apparatus a physical address of data targeted for duplication;

duplicating by a copy unit of the storage apparatus the data targeted for duplication based on the physical address of the data targeted for duplicating, in a separate region of the storage apparatus;

wherein the duplicating step is performed by the copy unit of the storage apparatus;

isolating by the copy unit of the storage apparatus the duplicated data based on an instruction from the NAS processing apparatus; and

setting by the copy unit of the storage apparatus one of the duplicated data as a snapshot.

12. A snapshot acquisition method according to claim 11, wherein the data is duplicated in units of data blocks.

13. A snapshot acquisition method according to claim 11, wherein the communication path is a network.

14. A storage system comprising:

a storage apparatus for storing data, the storage apparatus including a data duplicating device that duplicates data; and

a NAS processing apparatus that provides file service via a communication path and is connected to the storage apparatus, the NAS processing apparatus including a snapshot management device that manages snapshots,

wherein the snapshot management device issues to the data duplicating device a duplication instruction including a physical address of data targeted for duplication;

the duplicating device of the storage apparatus receives the duplication instruction from the snapshot management device and duplicates the data targeted for duplication based on the physical address of the data targeted for duplication issued from the snapshot management device of the NAS processing apparatus, isolates the duplicated data based on the duplication instruction from the NAS processing apparatus, and sets one of the duplicated data as a snapshot.

15. A snapshot acquisition method according to claim 14, wherein the communication path is a network.

16. A storage system according to claim 14, wherein the data is duplicated in units of data blocks.

17. A storage apparatus in combination that is controllable by a NAS processing apparatus that provides file service through a communication path, the storage apparatus comprising a copy device that copies data, wherein, upon receiving a data renewal request to renew data targeted for snapshot, the NAS processing apparatus issues a data copy instruction to the copy device of the storage apparatus to copy the data targeted for snapshot, and the copy device of the storage apparatus copies the data based on the received data copy instruction, and the copy device of the storage apparatus preserves the data in a separate region of the storage apparatus.

18. A snapshot acquisition method according to claim 17, wherein the data includes a plurality of files, and each of the files includes at least one block, wherein the data renewal request is an instruction to renew said at least one block in one of the files, wherein the copy device copies said at least one block in the separate region.

19. A snapshot acquisition method according to claim 17, wherein the data copy instruction designates a physical address of the data, a block length of the data, and a physical address at a copy destination where the data is copied.

20. A storage apparatus in combination that is controllable by a NAS processing apparatus that provides me service through a communication path, the storage apparatus comprising a duplicating device that duplicates data, wherein the duplicating device duplicates the data targeted for duplication based on a duplication instruction and physical address of the data targeted for duplication issued from the NAS processing apparatus, isolates the duplicated data based on the received duplication an instruction from the NAS processing apparatus, and sets one of the duplicated data as a snapshot.

21. A storage system according to claim 20, wherein the data is duplicated in units of data blocks.