Method and apparatus for managing replication volumes

• US 20040260873A1
• Filed: 06/17/2003
• Published: 12/23/2004
• Est. Priority Date: 06/17/2003
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Watanabe, Naoki
• Granted Patent: US 7,302,536 B2
• Time in Patent Office: Days
• US Class Current: 711/114
• CPC Class Codes: G06F 11/1456 Hardware arrangements for backup
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover

Abstract

Aspects of the invention provide for at least one first data portion of a first storage device in a system to be updated to a second storage and further replicating the update to a second data storage portion of the second storage device if a substantial system error fails to occur during the updating of the first data storage portion. Aspects can, for example, include facilitating restoration of a primary or secondary volume of a primary storage device or of a first or second secondary storage via secondary storage device copying, and/or alternative, alternating or internal/external application driven first and second (and/or further) secondary storage portion utilization. Aspects can also include state driven synchronization or re-synchronization of local and remote copies, or one or more of storage devices utilized can, for example, include a disk array.

Claims

1. A method, comprising:

receiving, by a secondary storage, a data update including primary storage data stored in a primary storage area of a primary storage;

synchronizing a first secondary storage area with the primary storage data;

determining if the synchronizing has been substantially successfully completed; and

synchronizing a second secondary storage area with first secondary storage area data of the first secondary storage area, if the synchronizing of the first secondary storage area has been substantially successfully completed.

2. A method according to claim 1, wherein at least one of the primary storage and the secondary storage comprises a disk array.

3. A method according to claim 2, wherein the disk array is configured as at least one of a redundant array of independent disks (“

RAID”

) and just a bunch of disks (“

JBOD”

).

4. A method according to claim 2, wherein the primary storage area comprises at least one of a primary volume, a primary volume group, a secondary volume and a secondary volume group.

5. A method according to claim 1, wherein the data update includes at least one of unmodified primary storage data in the primary storage area, and one or more modifications to the primary storage data.

6. A method according to claim 1, wherein the data update further includes a modification indicator indicating modifications made to one or more data portions of the primary storage area.

7. A method according to claim 6, wherein the modification indicator includes a modification map.

8. A method according to claim 6, wherein the data portions include at least one of data blocks and tracks.

9. A method according to claim 1, wherein the data update includes a data backup indicator.

10. A method according to claim 1, wherein the synchronizing a first secondary storage area includes copying one or more data portions of the primary storage data to one or more corresponding portions of the first secondary storage area.

11. A method according to claim 1, wherein the synchronizing a second secondary storage area includes replicating one or more data portions the first secondary storage data to one or more corresponding portions of the second secondary storage area.

12. Secondary storage data produced according to the method of claim 1.

13. A method according to claim 1, wherein the synchronizing of the second secondary storage area is conducted while the second secondary storage area is isolated from the first secondary storage area.

14. A secondary storage, comprising:

a storage controller;

storage media coupled to the storage controller; and

a replication manager coupled to the storage controller capable of, corresponding with a storing of primary data in a primary storage area of a primary storage, storing corresponding first secondary storage data in a remote copy area of the storage media and, if the storing corresponding data has been substantially successfully completed, also storing corresponding second secondary storage data in a local copy storage area of the storage media.

15. A secondary storage according to claim 14, wherein the storing corresponding first secondary storage data includes synchronizing the remote copy area with the primary storage area;

and wherein the storing corresponding second secondary storage data includes synchronizing the local copy area with the remote copy area.

16. A secondary storage according to claim 15, wherein the synchronizing the remote copy area includes copying one or more portions of the primary storage area to corresponding portions of the remote copy area, and the synchronizing the local copy area includes replicating portions of the local copy area with corresponding portions of the remote copy area.

17. A secondary storage according to claim 14, wherein the primary storage includes a disk array and the primary storage area includes at least one of a primary volume and a secondary volume of the primary storage.

18. A system, comprising:

receiving means for receiving, by a secondary storage, a data update including primary storage data stored in a primary storage area of a primary storage;

first synchronizing means for synchronizing a first secondary storage area with the primary storage data;

determining means for determining if the synchronizing has been substantially successfully completed; and

second synchronizing means for synchronizing a second secondary storage area with first secondary storage area data of the first secondary storage area, if the synchronizing of the first secondary storage area has been substantially successfully completed.

19. A computing system storing program code for causing the computing system to perform the steps of:

receiving, by a secondary storage, a data update including primary storage data stored in a primary storage area of a primary storage;

synchronizing a first secondary storage area with the primary storage data;

determining if the synchronizing has been substantially successfully completed; and

synchronizing a second secondary storage area with first secondary storage area data of the first secondary storage area, if the synchronizing of the first secondary storage area has been substantially successfully completed.

20. A method, comprising:

receiving, by a secondary storage, a data access request corresponding to primary data stored in a primary data storage area of a primary data storage;

selecting, by the secondary storage, a secondary data storage area from among at least a remote copy and a replicated copy corresponding to the primary storage data; and

accessing, by the secondary storage, the selected secondary storage area in response to the request.

21. A method according to claim 20, wherein at least one of the secondary storage and the primary storage includes a disk array.

22. A method according to claim 20, wherein the request corresponds to a data backup restore command.

23. A method according to claim 20, wherein the request corresponds to a data retrieval that has been re-directed from the primary storage to the secondary storage.

24. A method according to claim 23, wherein the request includes a data storage area indicator indicating a primary data storage area mapping.

25. A method according to claim 20, wherein the selecting imposes a preference for a first one of the remote copy and the replicated copy if the first one is determined to include valid data.

26. A method according to claim 20, wherein the access request includes a data retrieval request and the accessing includes retrieving data stored in the selected storage area.

27. A method according to claim 26, wherein the retrieving causes the retrieved data to be transferred to at least one of a primary storage host and an application server.

28. A method according to claim 20, further comprising causing data stored in a non-selected secondary storage area to be accessed in response to the request.

29. A secondary storage, comprising:

a storage controller;

storage media coupled to the storage controller; and

a replication manager coupled to the storage controller capable of receiving a data access request corresponding to primary data stored in a primary data storage area of a primary data storage, selecting a secondary data storage area from among at least a remote copy and a replicated copy corresponding to the primary storage data and accessing the selected secondary storage area in response to the request.

30. A method according to claim 29, wherein at least one of the secondary storage and the primary storage includes a disk array.

31. A secondary storage according to claim 30, wherein the request corresponds to at least one of a data backup restore command and a data retrieval that has been re-directed from the primary storage to the secondary storage.

32. A secondary storage according to claim 30, wherein the selecting imposes a preference for a first one of the remote copy and the replicated copy if the first one is determined to include valid data.

33. A method according to claim 30, wherein the access request includes a data retrieval request and the accessing includes causing data stored in the selected storage area to be retrieved and transferred to at least one of a primary storage host and an application server.

34. A system, comprising:

receiving means for receiving, by a secondary storage, a data access request corresponding to primary data stored in a primary data storage area of a primary data storage;

selecting means for selecting, by the secondary storage, a secondary data storage area from among at least a remote copy and a replicated copy corresponding to the primary storage data; and

accessing means for accessing, by the secondary storage, the selected secondary storage area in response to the request.

35. A computing system storing program code for causing the computing system to perform the steps of:

receiving, by a secondary storage, a data access request corresponding to primary data stored in a primary data storage area of a primary data storage;

selecting, by the secondary storage, a secondary data storage area from among at least a remote copy and a replicated copy corresponding to the primary storage data; and

accessing, by the secondary storage, the selected secondary storage area in response to the request.

36. A method, comprising:

determining that a remote copy data portion corresponding to a local copy data portion is to be synchronized; and

synchronizing the remote copy data portion by producing at least one of;

a first state in which the remote copy data portion is synchronized and suspended and the local copy data portion is synchronized and suspended, a second state in which the remote copy data portion is resynchonized and the local copy is synchronized and suspended, and a third state in which the remote copy data portion is synchronized and suspended and the local copy data portion is resynchronized.

37. A method of copying data among a primary volume, a first secondary volume and a second secondary volume, comprising:

isolating the first secondary volume from the primary volume;

isolating the second secondary volume from the first secondary volume;

re-synchronizing the first secondary volume with the primary volume; and

re-synchronizing the second secondary volume with the first secondary volume.

38. A protocol for managing a storage system having a first group of primary volumes and a second group of secondary volumes, comprising:

a first command for isolating the second group from the first group; and

a second command for synchronizing the second group with the first group.

39. A protocol according to claim 38, wherein the storage system has a first storage system and a second storage system, wherein the first group is stored in the first storage system and the second group is stored in the second storage system.