Method and apparatus for migrating data and automatically provisioning a target for the migration

• US 7,415,591 B1
• Filed: 04/23/2003
• Issued: 08/19/2008
• Est. Priority Date: 04/23/2003
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Todd, Stephen J., Blumenau, Steven M., Cakeljic, Zoran
• Primary Examiner(s): PEIKARI, BEHZAD
• Application Number:
  US10/421,239
• Time in Patent Office: 1,945 Days
• Field of Search: 711/161, 711/162, 711/165, 707/201, 707/202, 707/203, 707/204, 714/6
• US Class Current: 711/170
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 11/2071 using a plurality of controllers
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

Methods and apparatus for migrating a logical object. In one embodiment, a migration is performed by automatically determining the source location(s) of the logical object, moving the data stored therein to a target location while maintaining the availability of the data at the source location to an application program, and automatically servicing access requests from the application program at the target location after moving the data. In another embodiment, a migration is performed by automatically provisioning target location(s) to store a logical object, moving the data in the logical object to the target location(s) while maintaining its availability to an application program, and automatically servicing access requests from the application program at the target location after moving the data. In a further embodiment, a migration is performed by moving the data within a logical object from a source logical volume to a target logical volume, automatically servicing access requests from an application program at the target logical volume after moving the data, and retiring the source logical volume.

Claims

1. A method of migrating a logical object comprising a plurality of logically associated data elements from at least one first storage location at which the logical object is stored to at least one second storage location, the logical object storing data accessible to an application program, the method comprising computer-implemented acts of:

(A) in response to receipt of at least one instruction to migrate the logical object, automatically provisioning the at least one second storage location to service the logical object, the act of automatically provisioning comprising identifying the at least one second storage location and configuring the at least one second storage location to store the logical object;

(B) moving the data stored within the logical object from the at least one first storage location to the at least one second storage location;

(C) after completion of the act (B), automatically servicing access requests from the application program directed to the logical object from the at least one second storage location; and

(D) maintaining availability of the logical object to service access requests from the application program during the act (B).

2. The method of claim 1, wherein the act (B) includes an act of copying the data stored in the logical object from the at least one first storage location to the at least one second storage location.

3. The method of claim 1, wherein the act (D) includes an act of maintaining availability of the logical object to service access requests from the application program during acts (A), (B) and (C).

4. The method of claim 1, wherein the acts (A), (B) and (C) are performed in response to a single instruction to migrate the logical object.

5. The method of claim 1, wherein the method is performed in a computer system including at least one host computer and at least one storage system, wherein the at least one first storage location is provided in at least one first logical volume and the at least one second storage location is provided in at least one second logical volume, each of the logical volumes being presented by the at least one storage system to the at least one host computer and each being perceived by the at least one host computer as corresponding to a physical storage device, and wherein the act (B) includes an act of moving the data from the at least one first logical volume to the at least one second logical volume.

6. The method of claim 5, wherein the act (B) includes an act of creating at least one mirror between the at least one first logical volume and the at least one second logical volume and synchronizing the at least one mirror.

7. The method of claim 5, wherein the act (B) includes an act of creating at least one hardware mirror between the at least one first logical volume and the at least one second logical volume and synchronizing the at least one mirror.

8. The method of claim 5, wherein the act (C) includes an act of automatically redirecting access requests directed to the at least one first logical volume to the at least one second logical volume.

9. The method of claim 8, further comprising an act of, during the act (B), mirroring to the at least one second logical volume all writes to the at least one first logical volume.

10. The method of claim 5, further comprising an act of:

(E) retiring the at least one first logical volume upon completion of the act (C) so that the at least one first logical volume is no longer accessible.

11. The method of claim 5, wherein the at least one storage system includes first and second storage systems, wherein the at least one first logical volume is stored on the first storage system and the at least one second logical volume is stored on the second storage system.

12. The method of claim 5, wherein the at least one host computer includes at least one logical volume manager (LVM) that is assigned the at least one first logical volume and the at least one second logical volume, and wherein the act (B) is performed by the LVM.

13. The method of claim 5, wherein the act (A) includes an act of assigning data elements stored in the at least one first logical volume to physical addresses in the at least one second logical volume.

14. The method of claim 5, wherein the act (A) includes an act of configuring at least one switch through which the at least one host computer communicates with the at least one second logical volume.

15. The method of claim 1, wherein the act (D) includes an act of maintaining availability of the logical object to service write requests from the application program during the act (B).

16. The method of claim 1, wherein the act (B) is initiated automatically in response to completion of the act (A) and the act (C) is initiated automatically in response to completion of the act (B).

17. The method of claim 1, wherein the acts (A), (B), (C) and (D) are performed in a manner transparent to the application program.

18. The method of claim 1, wherein the logical object includes at least a portion of a database.

19. The method of claim 1, wherein the logical object includes a file system.

20. The method of claim 1, wherein the at least one first location includes a plurality of non-contiguous storage locations.

21. The method of claim 1, wherein the at least one second location includes a plurality of non-contiguous storage locations.

22. The method of claim 1, wherein the method is performed in a computer system including at least one host computer and at least one storage system, wherein the application program executes on the at least one host computer, and wherein the method is performed by at least one utility executing on the computer system.

23. The method of claim 1, further including an act of, following completion of the act (C), performing all writes to the logical object at both the at least one first storage location and the at least one second storage location.

24. At least one computer-readable medium with instructions encoded thereon for performing a method of migrating a logical object comprising a plurality of logically associated data elements from at least one first storage location at which the logical object is stored to at least one second storage location, the logical object storing data accessible to an application program, the method comprising acts of:

(A) in response to receipt of at least one instruction to migrate the logical object, automatically provisioning the at least one second storage location to service the logical object, the act of automatically provisioning comprising identifying the at least one second storage location and configuring the at least one second storage location to store the logical object;

(B) moving the data stored within the logical object from the at least one first storage location to the at least one second storage location;

(C) after completion of the act (B), automatically servicing access requests from the application program directed to the logical object from the at least one second storage location; and

(D) maintaining availability of the logical object to service access requests from the application program during the act (B).

25. The at least one computer-readable medium of claim 24, wherein the act (B) includes an act of copying the data stored in the logical object from the at least one first storage location to the at least one second storage location.

26. The at least one computer-readable medium of claim 24, wherein the act (D) includes an act of maintaining availability of the logical object to service access requests from the application program during acts (A), (B) and (C).

27. The at least one computer-readable medium of claim 24, wherein the acts (A), (B) and (C) are performed in response to a single instruction to migrate the logical object.

28. The at least one computer-readable medium of claim 24, wherein the method is performed in a computer system including at least one host computer and at least one storage system, wherein the at least one first storage location is provided in at least one first logical volume and the at least one second storage location is provided in at least one second logical volume, each of the logical volumes being presented by the at least one storage system to the at least one host computer and each being perceived by the at least one host computer as corresponding to a physical storage device, and wherein the act (B) includes an act of moving the data from the at least one first logical volume to the at least one second logical volume.

29. The at least one computer-readable medium of claim 28, wherein the act (B) includes an act of creating at least one mirror between the at least one first logical volume and the at least one second logical volume and synchronizing the at least one mirror.

30. The at least one computer-readable medium of claim 28, wherein the act (B) includes an act of creating at least one hardware mirror between the at least one first logical volume and the at least one second logical volume and synchronizing the at least one mirror.

31. The at least one computer-readable medium of claim 28, wherein the act (C) includes an act of automatically redirecting access requests directed to the at least one first logical volume to the at least one second logical volume.

32. The at least one computer-readable medium of claim 31, wherein the method further comprises an act of, during the act (B), mirroring to the at least one second logical volume all writes to the at least one first logical volume.

33. The at least one computer-readable medium of claim 28, wherein the method further comprising an act of:

(E) retiring the at least one first logical volume upon completion of the act (C) so that the at least one first logical volume is no longer accessible.

34. The at least one computer-readable medium of claim 28, wherein the at least one storage system includes first and second storage systems, wherein the at least one first logical volume is stored on the first storage system and the at least one second logical volume is stored on the second storage system.

35. The at least one computer-readable medium of claim 28, wherein the at least one host computer includes at least one logical volume manager (LVM) that is assigned the at least one first logical volume and the at least one second logical volume, and wherein the act (B) is performed by the LVM.

36. The at least one computer-readable medium of claim 28, wherein the act (A) includes an act of assigning data elements stored in the at least one first logical volume to physical addresses in the at least one second logical volume.

37. The at least one computer-readable medium of claim 28, wherein the act (A) includes an act of configuring at least one switch through which the at least one host computer communicates with the at least one second logical volume.

38. The at least one computer-readable medium of claim 24, wherein the act (D) includes an act of maintaining availability of the logical object to service write requests from the application program during the act (B).

39. The at least one computer-readable medium of claim 24, wherein the act (B) is initiated automatically in response to completion of the act (A) and the act (C) is initiated automatically in response to completion of the act (B).

40. The at least one computer-readable medium of claim 24, wherein the acts (A), (B), (C) and (D) are performed in a manner transparent to the application program.

41. The at least one computer-readable medium of claim 24, wherein the logical object includes at least a portion of a database.

42. The at least one computer-readable medium of claim 24, wherein the logical object includes a file system.

43. The at least one computer-readable medium of claim 24, wherein the at least one first location includes a plurality of non-contiguous storage locations.

44. The at least one computer-readable medium of claim 24, wherein the at least one second location includes a plurality of non-contiguous storage locations.

45. The at least one computer-readable medium of claim 24, wherein the method is performed in a computer system including at least one host computer and at least one storage system, wherein the application program executes on the at least one host computer, and wherein the method is performed by at least one utility executing on the computer system.

46. The at least one computer-readable medium of claim 24, wherein the method further includes an act of, following completion of the act (C), performing all writes to the logical object at both the at least one first storage location and the at least one second storage location.

47. An apparatus for migrating a logical object comprising a plurality of logically associated data elements from at least one first storage location at which the logical object is stored to at least one second storage location, the logical object storing data accessible to an application program, the apparatus comprising at least one processor programmed to:

in response to receipt of at least one instruction to migrate the logical object, automatically provision the at least one second storage location to service the logical object, the automatic provisioning comprising identifying the at least one second storage location and configuring the at least one second storage location to store the logical object;

move the data stored within the logical object from the at least one first storage location to the at least one second storage location;

after the move of the data, automatically service access requests from the application program directed to the logical object from the at least one second storage location; and

maintain availability of the logical object to service access requests from the application program during the move of the data.

48. The apparatus of claim 47, wherein the at least one processor is programmed to copy the data stored in the logical object from the at least one first storage location to the at least one second storage location.

49. The apparatus of claim 47, wherein the at least one processor is programmed to maintain availability of the logical object to service access requests from the application program during the migration of the logical object.

50. The apparatus of claim 47, wherein the at least one processor is programmed to perform the migration of the logical object in response to a single instruction to migrate the logical object.

51. The apparatus of claim 47, wherein the migration of the logical object is performed in a computer system including at least one host computer and at least one storage system, wherein the at least one first storage location is provided in at least one first logical volume and the at least one second storage location is provided in at least one second logical volume, each of the logical volumes being presented by the at least one storage system to the at least one host computer and each being perceived by the at least one host computer as corresponding to a physical storage device, and wherein the at least one processor is programmed to move the data from the at least one first logical volume to the at least one second logical volume.

52. The apparatus of claim 51, wherein the at least one processor is programmed to create at least one mirror between the at least one first logical volume and the at least one second logical volume and synchronize the at least one mirror.

53. The apparatus of claim 51, wherein the at least one processor is programmed to create at least one hardware mirror between the at least one first logical volume and the at least one second logical volume and synchronize the at least one mirror.

54. The apparatus of claim 51, wherein the at least one processor is programmed to automatically redirect access requests directed to the at least one first logical volume to the at least one second logical volume.

55. The apparatus of claim 54, wherein the at least one processor is programmed to, during the move of the data, mirror to the at least one second logical volume all writes to the at least one first logical volume.

56. The apparatus of claim 51, wherein the at least one processor is programmed to retire the at least one first logical volume upon completion of the automatic service of access requests from the application program directed to the logical object from the at least one second storage location so that the at least one first logical volume is no longer accessible.

57. The apparatus of claim 51, wherein the at least one storage system includes first and second storage systems, wherein the at least one first logical volume is stored on the first storage system and the at least one second logical volume is stored on the second storage system.

58. The apparatus of claim 51, wherein the at least one host computer includes at least one logical volume manager (LVM) that is assigned the at least one first logical volume and the at least one second logical volume, and wherein the at least one processor is programmed to perform the move of the data stored within the logical object from the at least one first storage location to the at least one second storage location using the LVM.

59. The apparatus of claim 51, wherein the at least one processor is programmed to assign data elements stored in the at least one first logical volume to physical addresses in the at least one second logical volume.

60. The apparatus of claim 51, wherein at least one processor is programmed to configure at least one switch through which the at least one host computer communicates with the at least one second logical volume.

61. The apparatus of claim 47, wherein the at least one processor is programmed to maintain availability of the logical object to service write requests from the application program during the move of the data.

62. The apparatus of claim 47, wherein the at least one processor is programmed to automatically initiate the move of the data stored within the logical object from the at least one first storage location to the at least one second storage location in response to completion of the automatic provisioning of the at least one second storage location to service the logical object, and the automatic service of access requests from the application program directed to the logical object from the at least one second storage location is initiated automatically in response to completion of the move of the data stored within the logical object from the at least one first storage location to the at least one second storage location.

63. The apparatus of claim 47, wherein the migration of the logical object is performed in a manner transparent to the application program.

64. The apparatus of claim 47, wherein the logical object includes at least a portion of a database.

65. The apparatus of claim 47, wherein the logical object includes a file system.

66. The apparatus of claim 47, wherein the at least one first location includes a plurality of non-contiguous storage locations.

67. The apparatus of claim 47, wherein the at least one second location includes a plurality of non-contiguous storage locations.

68. The apparatus of claim 47, wherein the migration of the logical object is performed in a computer system including at least one host computer and at least one storage system, wherein the application program executes on the at least one host computer, and wherein the at least one processor is programmed to perform the migration of the logical object using at least one utility executing on the computer system.

69. The apparatus of claim 47, wherein the at least one processor is programmed to, after initiating the automatic service of access requests from the application program directed to the logical object from the at least one second storage location, perform all writes to the logical object at both the at least one first storage location and the at least one second storage location.