Systems, methods and apparatus for creating stable disk images

• US 6,850,945 B2
• Filed: 02/28/2002
• Issued: 02/01/2005
• Est. Priority Date: 02/28/2002
• Status: Expired due to Term

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Veritas Operating Corporation (Gen Digital Inc.)
• Inventors: Kiselev, Oleg, Colgrove, John A., Bromley, Graham, Umbehocker, Steven Michael, Harmer, Craig, Lanzatella, Thomas W., Karr, Ron, Unueco, Allen, Cuykendall, Blaine T.
• Primary Examiner(s): Alam, Shahid
• Assistant Examiner(s): TRUONG, CAM Y T
• Application Number:
  US10/087,230
• Publication Number:
  US 20030163476A1
• Time in Patent Office: 1,069 Days
• Field of Search: 707/1, 707/10, 707/100, 707/3, 707/8, 711/162
• US Class Current: 707/649
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0605 by facilitating the interaction with a user or administrator
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0626 Reducing size or complexity of storage systems
• CPC Class Codes: G06F 3/0638 Organizing or formatting or addressing of data
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0662 Virtualisation aspects
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A system and method of identifying methods of quiescing a storage object. Data is received identifying the storage object and a freeze list is generated. The freeze list includes one or more freeze methods appropriate for quiescing the storage object. Generating includes creating a hierarchy of logical storage objects below the identified storage object, associating quiesce characteristics with each logical storage object below the identified storage object and generating freeze vectors as a function of quiesce characteristics associated with each logical storage object below the identified storage object.

Claims

1. A method of generating a frozen image of a system having a plurality of logical storage objects, including a first logical storage object, wherein the first logical storage object includes a storage device, the method comprising:

building a logical storage tree with the first logical storage object as the root object and with the storage device as a leaf node;

starting at the leaf node, constructing a freeze list for freezing the first logical storage object, wherein the freeze list includes one or more freeze methods, and wherein a given freeze methods includes operations configured to generate a frozen image of the leaf node according to storage device split and quiesce characteristics;

modifying the freeze list as a function of traversing the logical storage tree to the root object, wherein modifying includes adding information about split and quiesce characteristics for logical storage objects between the root object and the leaf node;

selecting a freeze method from the freeze list; and

freezing the first logical storage object using the selected freeze method.

2. The method of claim 1, wherein freezing the first logical storage object includes quiescing the storage device.

3. The method of claim 1, wherein freezing the first logical storage object includes quiescing from the root object out to the leaf node.

4. The method of claim 1, wherein building a logical storage tree includes:

determining location of each logical storage object; and

receiving information about logical storage object split and quiesce characteristics from each of the plurality of logical storage objects.

5. The method of claim 4, wherein receiving information about logical storage object split and quiesce characteristics includes calling a plug-in software component associated with each of the plurality of logical storage objects.

6. The method of claim 1, wherein selecting a freeze method from the freeze list includes:

determining a quality of quiesce for each of the freeze methods on the freeze list; and

choosing the freeze method with the highest quality of quiesce.

7. The method of claim 1, wherein selecting a freeze method from the freeze list includes:

selecting a type of freeze method; and

choosing from freeze methods of the selected freeze method type.

8. The method of claim 1, wherein selecting a freeze method from the freeze list includes:

selecting a type of freeze method;

determining a quality of quiesce for each of the freeze methods on the freeze list; and

choosing the freeze method with the highest quality of quiesce from freeze methods of the selected freeze method type.

9. The method of claim 1, wherein a storage management stack having a plurality of levels is associated with each of the plurality of logical storage objects, and wherein building the logical storage tree includes traversing the storage management stack.

10. The method of claim 1, wherein modifying the freeze list includes determining whether a logical storage object spans multiple stable image data sources.

11. The method of claim 1, wherein modifying the freeze list includes determining all forms of stable disk image capability provided by each logical storage object.

12. The method of claim 1, wherein modifying the freeze list includes determining an optimal form of stable disk image capability for each of the plurality of logical storage objects from the all forms.

13. The method of claim 1, wherein adding information about split and quiesce characteristics includes calculating quiesce strength for one or more freeze methods while traversing the logical storage tree.

14. The method of claim 1, wherein adding information about split and quiesce characteristics includes calculating quiesce strength as a function of a quiesce operation associated with a quiesce node.

15. The method of claim 1, wherein modifying the freeze list further includes reviewing split types.

16. The method of claim 1, wherein modifying the freeze list further includes grouping nodes with similar split characteristics together for the purpose of determining what nodes are affected when split operations are executed.

17. The method of claim 16, wherein grouping includes gauging split operation quality.

18. The method of claim 1, wherein modifying the freeze list further includes grouping nodes with similar quiesce characteristics together for the purpose of determining what nodes are affected when quiesce operations are executed.

19. The method of claim 18, wherein grouping includes gauging quiesce operation quality.

20. A computer-accessible medium having executable instructions to generate a frozen image of a system having a plurality of logical storage objects, including a first logical storage object, wherein the first logical storage object includes a storage device, the executable instructions capable of directing a processor to perform:

building a logical storage tree with the first logical storage object as the root object and with the storage device as a leaf node;

starting at the leaf node, constructing a freeze list for freezing the first logical storage object, wherein the freeze list includes one or more freeze methods, and wherein a given freeze methods includes operations configured to generate a frozen image of the leaf node according to storage device split and quiesce characteristics;

modifying the freeze list as a function of traversing the logical storage tree from the leaf node to the root object, wherein modifying includes adding information about split and quiesce characteristics for logical storage objects between the root object and the leaf node;

selecting a freeze method from the freeze list; and

freezing the volume using the selected freeze method.

21. The computer-accessible medium of claim 20, wherein freezing the volume includes quiescing the storage device.

22. The computer-accessible medium of claim 20, wherein freezing the volume includes quiescing from the root object out to the leaf node.

23. The computer-accessible medium of claim 20, wherein building a logical storage tree includes:

determining a location for each logical storage object; and

receiving information about logical storage object split and quiesce characteristics from each of the plurality of logical storage objects.

24. The computer-accessible medium of claim 23, wherein receiving information about logical storage object split and quiesce characteristics includes calling a plug-in software component associated with each of the plurality of logical storage objects.

25. The computer-accessible medium of claim 20, wherein selecting a freeze method from the freeze list includes:

determining a quality of quiesce for each of the freeze methods on the freeze list; and

choosing the freeze method with the highest quality of quiesce.

26. The computer-accessible medium of claim 20, wherein selecting a freeze method from the freeze list includes:

selecting a type of freeze method; and

choosing from freeze methods of the selected freeze method type.

27. The computer-accessible medium of claim 20, wherein selecting a freeze method from the freeze list includes:

selecting a type of freeze method;

determining a quality of quiesce for each of the freeze methods on the freeze list; and

choosing the freeze method with the highest quality of quiesce from freeze methods of the selected freeze method type.

28. The computer-accessible medium of claim 20, wherein a storage management stack having a plurality of levels is associated with each of the plurality of logical storage objects, and wherein building the logical storage tree includes traversing the storage management stack.

29. The computer-accessible medium of claim 20, wherein modifying the freeze list includes determining whether a logical storage object spans multiple stable image data sources.

30. The computer-accessible medium of claim 20, wherein modifying the freeze list includes determining all forms of stable disk image capability provided by each logical storage object.

31. The computer-accessible medium of claim 20, wherein modifying the freeze list includes determining an optimal form of stable disk image capability for each of the plurality of logical storage objects from the all forms.

32. The computer-accessible medium of claim 20, wherein adding information about split and quiesce characteristics includes calculating quiesce strength for one or more freeze methods while traversing the logical storage tree.

33. The computer-accessible medium of claim 20, wherein adding information about split and quiesce characteristics includes calculating quiesce strength as a function of a quiesce operation associated with a quiesce node.

34. The computer-accessible medium of claim 20, wherein modifying the freeze list further includes reviewing split types.

35. A method of generating a frozen image of a volume having one or more storage devices, the method comprising:

receiving information about storage device split and quiesce characteristics from the storage devices;

storing the information regarding storage device split and quiesce characteristics;

creating a freeze list for freezing the volume having one or more freeze methods, wherein a given freeze method includes operations configured to generate a frozen image according to storage device split and quiesce characteristics, and wherein creating a freeze list includes combining information about volume split and quiesce characteristics with information regarding storage device split and quiesce characteristics;

selecting a freeze method from the freeze list; and

freezing the volume using the selected freeze method.

36. The method of claim 35, wherein freezing the volume includes quiescing each of the storage devices.

37. The method of claim 35, wherein freezing the volume includes quiescing the volume and each of the storage devices.

38. The method of claim 35, wherein combining information includes calculating quiesce strength for one of the freeze methods while traversing the logical storage tree.

39. The method of claim 38, wherein combining information includes calculating quiesce strength as a function of a quiesce operation associated with a quiesce node.

40. The method of claim 35, wherein combining information includes reviewing split types.