Data restoring method and an apparatus using journal data and an identification information

• US 7,185,227 B2
• Filed: 04/30/2003
• Issued: 02/27/2007
• Est. Priority Date: 02/20/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mogi, Kazuhiko, Oeda, Takashi, Yamamoto, Yasutomo, Eguchi, Yoshiaki, Arai, Kouji
• Primary Examiner(s): Beausoliel; Robert
• Assistant Examiner(s): GUYTON, PHILIP A
• Application Number:
  US10/428,204
• Publication Number:
  US 20040193945A1
• Time in Patent Office: 1,399 Days
• Field of Search: None
• US Class Current: 714/15
• CPC Class Codes: G06F 11/142 Reconfiguring to eliminate the error group management mechanisms in a peer-to-peer network H04L67/1044
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A host and a storage system each keep a shared identifier indicating a state of a system. The storage system acquires, at update of data, a data pair including data for a change through processing of the host and data before the update. The storage system relates the data pair to a shared identifier. When the host indicates an identifier, the storage system restores data using the data pair.

Claims

1. An information processing system comprising:

a computer; and

a storage system, coupled to the computer, which receives a write request from the computer;

wherein the storage system further comprises;

a control unit processing the write request from the computer;

a first storage, coupled to the control unit, which stores data related to the write request targeted to the first storage from the computer;

a second storage, coupled to the control unit, which stores a copy of data of the first storage at a first point in time; and

a third storage, coupled to the control unit, which records, write data related to the write request targeted to the first storage from the computer with time information and/or sequence numbers, and a plurality of checkpoints in time for recovery received from the computer, as journal data of the first storage, wherein the checkpoints uniquely identify a system state in the computer and the storage system;

wherein when the control unit receives a restoration request including a desired checkpoint information specifying one of the plurality of checkpoints, the information processing system generates an image of the first storage at a desired point in time specified with the desired checkpoint information based upon the copied data stored in the second storage, and journal data which are stored in the third storage and which are specified by the desired checkpoint and the first point in time.

2. An information processing system according to claim 1, wherein the first, second, and third storages are logical storages.

3. An information processing system according to claim 2, further comprising a second computer coupled to the storage system,

wherein the write request is sent from the second computer to the storage system.

4. An information processing system according to claim 1, wherein the computer comprises a storage and records the checkpoint information in the storage of the computer.

5. An information processing system according to claim 1, wherein the information processing system further comprises a management terminal including a display for displaying thereon information regarding the checkpoint information.

6. An information processing system according to claim 5, wherein the management terminal includes an input unit and transmits the checkpoint information specified by information inputted from the input unit to the storage system.

7. An information processing system according to claim 1, wherein at least some of the checkpoints are created by the computer when the computer receives a notification from the control unit indicating completion of a write request to write dirty data from the computer to the storage system.

8. A storage system coupled to a computer comprising:

a control unit processing a write request from the computer;

a first storage, coupled to the control unit, which stores data related to the write request targeted to the first storage from the computer;

a second storage, coupled to the control unit, which stores a copied data of the first storage; and

a third storage, coupled to the control unit, which records, write data related to the write request targeted to the first storage from the computer with time information and/or sequence numbers, and a plurality of checkpoints in time for recovery received from the computer, as journal data of the first storage, wherein the checkpoints uniquely identify a system state in the computer and the storage system;

wherein the control unit receives checkpoint information indicating timing information from the computer, and stores the checkpoint information in the storage system, and

wherein when the control unit receives a restoration request including a desired checkpoint information specifying one of the checkpoints, the control unit executes the restoration in response to the restoration request so that an image of the first storage at a desired point in time specified with the desired checkpoint information is created based upon the copied data stored in the second storage, and journal data which are stored in the third storage and which are specified by the desired checkpoint.

9. A storage system according to claim 8, wherein the first, second, and third storages are logical storages.

10. A storage system according to claim 9, further comprising a second computer coupled to the storage system,

wherein the write update request is sent from the second computer to the storage system.

11. A storage system according to claim 8, wherein at least some of the checkpoints are created by the computer when the computer receives a notification from the control unit indicating completion of a write request to write dirty data from the computer to the storage system.

12. A data restoration method in an information processing system comprising the steps of:

receiving a write request from a computer at a storage system;

storing data related to the write request targeted to a volume in the storage system;

storing write data of journal data related to the write request targeted to the volume from the computer in a storing area in the storage system;

generating a copy of the volume in the storage system;

recording data which contains time information and/or sequence numbers received from the computer, associated with the write request received at the storage system;

recording a plurality of checkpoints in time for recovery that are received from the computer, and which identify system states in the computer and the storage system, respectively;

managing a relationship between a plurality of checkpoints and the recorded data in a portion of the information processing system outside of the computer;

receiving a restore request specifying checkpoint information of one of the checkpoints; and

restoring, in the portion of the information processing system outside of the computer and in response to the restore request, an image of the volume based upon the copy of the volume in the storage system, and based upon the write data of the journal data associated with the recorded data specified by the checkpoint information.

13. A data restoration method according to claim 12, wherein the checkpoint information contains information corresponding to the recorded time information and/or sequence numbers.

14. A data restoration method according to claim 12, wherein the system state is one in which the computer and the storage system are consistent.

15. A data restoration method according to claim 12, wherein the restoring the image of the first storing area is performed in response to a restore request from a management computer.

16. A data restoration method according to claim 15, further comprising displaying information regarding the checkpoint information which is recorded in the computer.

17. A data restoration method according to claim 12, wherein at least some of the checkpoints are created by the computer when the computer receives a notification from the control unit indicating completion of a write request to write dirty data from the computer to the storage system.

18. A data restoration method in an information processing system comprising the steps of:

receiving a write request from a computer at a storage system;

storing data related to the write request targeted to a volume in the storage system;

storing write data of journal data related to the write request targeted to the volume from the computer in a storing area in the storage system;

generating a copy of the volume in the storage system;

recording data which contains time information and/or sequence numbers received from the computer, associated with the write request received at the storage system;

recording a plurality of checkpoints in time for recovery received from the computer;

managing a relationship between a plurality of checkpoints and the recorded data in a portion of the information processing system outside of the computer, at least some of the checkpoints are created by the computer to particularly identify points in time at which the data in the storage system matches the data in the computer;

receiving a restore request specifying checkpoint information of one of the checkpoints; and

restoring, in the portion of the information processing system outside of the computer and in response to the restore request, an image of the volume based upon the copy of the volume in the storage system, and the write data of the journal data associated with the recorded data which are specified by the checkpoint information.

19. A data restoration method according to claim 18, wherein the checkpoint information contains information corresponding to the recorded time information and/or sequence numbers.

20. A data restoration method according to claim 19, wherein the system state is one in which the computer and the storage system are consistent.

21. A data restoration method according to claim 18, wherein the restoring the image of the first storing area is performed in response to a restore request from a management computer.

22. A data restoration method according to claim 21, further comprising displaying information regarding the checkpoint information stored in the computer.

23. A data restoration method according to claim 18, wherein at least some of the checkpoints are created by the computer when the computer receives a notification from the control unit indicating completion of a write request to write dirty data from the computer to the storage system.

24. A data restoration method in an information processing system comprising the step of:

receiving a write request from a computer at a storage system;

storing data related to the write request targeted to a volume in the storage system;

storing write data of journal data related to the write request targeted to the volume from the computer in a storing area in the storage system;

generating a copy of the volume in the storage system at a first point in time;

recording data which contains time information and/or sequence numbers received from the computer, associated with the write request received at the storage system;

recording a plurality of checkpoints in time for recovery received from the computer;

managing a relationship between a plurality of checkpoints and the recorded data in the storage system, wherein the checkpoint indicates a system state in which the computer and the storage system are consistent;

receiving a restore request specifying checkpoint information of one of the checkpoints; and

restoring, in the storage system and in response to the restore request, an image of the volume based upon the copy of the volume in the storage system at the first point in time, and the write data of the journal data associated with the recorded data which are specified by the checkpoint information and the first point in time.

25. A data restoration method according to claim 24, wherein the checkpoint information contains information corresponding to the recorded time information and/or sequence numbers.

26. A data restoration method according to claim 24, wherein the restoring the image of the first storing area is performed in response to a restore request from a management computer.

27. A data restoration method according to claim 26, further comprising displaying information regarding the checkpoint information stored in the computer.

28. A data restoration method according to claim 24, wherein at least some of the checkpoints are created by the computer when the computer receives a notification from the control unit indicating completion of a write request to write dirty data from the computer to the storage system.