Data migration method for disk apparatus

• US 7,231,466 B2
• Filed: 06/15/2006
• Issued: 06/12/2007
• Est. Priority Date: 06/24/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Okada, Koichi, Tamura, Akiyori
• Primary Examiner(s): Park; Ilwoo
• Application Number:
  US11/452,974
• Publication Number:
  US 20060236006A1
• Time in Patent Office: 362 Days
• Field of Search: None
• US Class Current: 710/5
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• 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]
• CPC Class Codes: G06F 3/0683 Plurality of storage devices

Abstract

Data migration can be executed between new and old disk apparatuses without changing the disk definition of a host computer. A switch having the function of online data migration is provided between the host computer and the old disk apparatus, data are copied to the new disk apparatus while the disk apparatus is accessed continuously by the host computer. If a SCSI command for identifying disk apparatuses is issued by the host computer after data migration, the response of the old disk apparatus is sent back.

Claims

1. A method of controlling data transfer in a switch system coupled to an initiator and a plurality of storage devices, the initiator using logical unit identification information of a logical unit to access the switch system, and each of the storage devices having a plurality of disk drives, the method comprising:

a first status comprising;

receiving data of a first data input request, the first data input request being sent from the initiator and being targeted to the logical unit identification information, and

transferring the data of the first data input request to a first storage device of the storage devices so that the first storage device inputs the data of the first data input request into a storage area of the disk drives of the first storage device;

a second status comprising;

transferring data stored in the first storage device to a second storage device of the storage devices,

a third status comprising;

receiving data of a second data input request, the second data input request being sent from the initiator and being targeted to the logical unit identification information, and

transferring the data of the second data input request to the second storage device so that the second storage device inputs the data of the second data input request into a storage area of the disk drives of the second storage device,

wherein the second status is conducted between the first status and the third status, and

wherein the switch system controls to allow or deny authorizing a reserve to the initiator based on whether or not another initiator is allowed authorizing the reserve authority of the logical unit of the logical unit identification information.

2. The method of controlling data transfer according to claim 1, wherein the switch system controls to allow or deny authorizing the reserve to the other initiator during at least the second status.

3. The method of controlling data transfer according to claim 1, wherein the switch system controls to allow or deny authorizing the reserve to the initiator based on a command, the command being used to request a reserve and being sent from the initiator.

4. The method of controlling data transfer according to claim 1, wherein the switch system controls to allow authorizing the reserve to the initiator and controls to release the logical unit of the logical unit identification information from the initiator.

5. The method of controlling data transfer according to claim 1, wherein the switch system controls to allow authorizing the reserve to the initiator based on a first command sent from the initiator and controls to release the logical unit of the logical unit identification information from the initiator based on a second command sent from the initiator.

6. The method of controlling data transfer according to claim 1, wherein the switch system controls to allow or deny authorizing the reserve to the initiator based on a Reserve command of SCSI standards.

7. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls a Test Unit Ready command of SCSI standards.

8. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls a Rezero Unit command of SCSI standards.

9. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls a Request Sense command of SCSI standards.

10. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls a Format command of SCSI standards.

11. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls an Inquiry command of SCSI standards.

12. The method of controlling data transfer according to claim 1, wherein the switch system receives and controls a Verify command of SCSI standards.

13. The method of controlling data transfer according to claim 1, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the logical unit is continuously accessed by the initiator.

14. The method of controlling data transfer according to claim 1, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the logical unit is continuously accessed by the initiator, the initiator is allowed authorizing the reserve of the logical unit.

15. The method of controlling data transfer according to claim 1, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the initiator does not need to change the definition of the logical unit and tasks of the initiator can be performed continuously.

16. The method of controlling data transfer according to claim 1, wherein the transferring step, for transferring the data stored in the first storage device to the second storage device, is executed by a data migration function in the switch system.

17. The method of controlling data transfer according to claim 1, wherein the switch system controls to deny authorizing the reserve to the initiator and the another initiator is allowed authorizing the reserve of the logical unit of the logical unit identification information.

18. A method of controlling data transfer in a switch system coupled to an initiator and a plurality of storage devices, the initiator using an identification information to access the switch system, and each of the storage devices having a plurality of disk drives, the method comprising:

controlling to allow or deny reserving a logical unit for the initiator based on whether or not the logical unit is reserved for another initiator;

receiving data of a first data input request, the first data input request being sent from the initiator and being targeted to the identification information;

transferring the data of the first data input request to a first storage device of the storage devices so that the first storage device inputs the data of the first data input request into a storage area of the disk drives of the first storage device;

transferring data stored in the first storage device to a second storage device of the storage devices;

receiving data of a second data input request, the second data input request being sent from the initiator and being targeted to the identification information; and

transferring the data of the second data input request to the second storage device so that the second storage device inputs the data of the second data input request into a storage area of the disk drives of the second storage device.

19. The method of controlling data transfer according to claim 18, wherein the switch system controls to allow or deny to reserve the logical unit for the other initiator during at least the transferring step for transferring data stored in the first storage device to the second storage device.

20. The method of controlling data transfer according to claim 18, wherein the switch system controls to allow or deny reserving the logical unit for the initiator based on a command, the command being used to request a reserve and being sent from the initiator.

21. The method of controlling data transfer according to claim 18, wherein the switch system controls to allow reserving the logical unit for the initiator and controls to release the logical unit from the initiator.

22. The method of controlling data transfer according to claim 18, wherein the switch system controls to allow reserving the logical unit for the initiator based on a first command sent from the initiator and controls to release the logical unit from the initiator based on a second command sent from the initiator.

23. The method of controlling data transfer according to claim 18, wherein the switch system controls to allow or deny reserving the logical unit for the initiator based on a Reserve command of SCSI standards.

24. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls a Test Unit Ready command of SCSI standards.

25. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls a Rezero Unit command of SCSI standards.

26. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls a Request Sense command of SCSI standards.

27. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls a Format command of SCSI standards.

28. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls an Inquiry command of SCSI standards.

29. The method of controlling data transfer according to claim 18, wherein the switch system receives and controls a Verify command of SCSI standards.

30. The method of controlling data transfer according to claim 18, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the logical unit is continuously accessed by the initiator.

31. The method of controlling data transfer according to claim 18, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the logical unit is continuously accessed by the initiator, the initiator being allowed reserving the logical unit.

32. The method of controlling data transfer according to claim 18, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the initiator does not need to change the definition of the logical unit and tasks of the initiator can be performed continuously.

33. The method of controlling data transfer according to claim 18, wherein the transferring step, for transferring the data stored in the first storage device to the second storage device, is executed by a data migration function in the switch system.

34. The method of controlling data transfer according to claim 18, wherein the switch system controls to deny reserving the logical unit for the initiator, if the logical unit is reserved for the another initiator.

35. A method of controlling data transfer in a switch system coupled to an initiator and a plurality of storage devices, the initiator using an identification information to access the switch system, and each of the storage devices having a plurality of disk drives, the method comprising:

controlling to allow or deny reserving a storage target for the initiator;

receiving data of a first data write request, the first data write request being sent from the initiator and being targeted to the identification information;

transferring the data of the first data write request to a first storage device of the storage devices so that the first storage device writes the data of the first data write request into a storage area of the disk drives of the first storage device;

transferring data stored in the first storage device to a second storage device of the storage devices;

receiving data of a second data write request, the second data write request being sent from the initiator and being targeted to the identification information; and

transferring the data of the second data write request to the second storage device so that the second storage device writes the data of the second data write request into a storage area of the disk drives of the second storage device.

36. The method of controlling data transfer according to claim 35, wherein the switch system controls to allow or deny reserving the storage target for the other initiator during at least the transferring step for transferring data stored in the first storage device to the second storage device.

37. The method of controlling data transfer according to claim 35, wherein the switch system controls to allow or deny reserving the storage target for the initiator based on a command, the command being used to request a reserve and being sent from the initiator.

38. The method of controlling data transfer according to claim 35, wherein the switch system controls to allow or deny reserving the storage target for the initiator and controls to release the logical unit from the initiator.

39. The method of controlling data transfer according to claim 35, wherein the switch system controls to allow or deny reserving the storage target for the initiator based on a first command sent from the initiator and controls to release the logical unit from the initiator based on a second command sent from the initiator.

40. The method of controlling data transfer according to claim 35, wherein the switch system controls to allow or deny reserving the storage target for the initiator based on a Reserve command of SCSI standards.

41. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls a Test Unit Ready command of SCSI standards.

42. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls a Rezero Unit command of SCSI standards.

43. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls a Request Sense command of SCSI standards.

44. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls a Format command of SCSI standards.

45. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls an Inquiry command of SCSI standards.

46. The method of controlling data transfer according to claim 35, wherein the switch system receives and controls a Verify command of SCSI standards.

47. The method of controlling data transfer according to claim 35, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the storage target of the identification information is continuously accessed by the initiator.

48. The method of controlling data transfer according to claim 35, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the storage target of the identification information is continuously accessed by the initiator, the initiator being allowed reserving the storage target.

49. The method of controlling data transfer according to claim 35, wherein the switch system controls to transfer the data stored in the first storage device to the second storage device in a status in which the initiator does not need to change the definition of the storage target and tasks of the initiator can be performed continuously.

50. The method of controlling data transfer according to claim 35, wherein the transferring step, for transferring the data stored in the first storage device to the second storage device, is executed by a data migration function in the switch system.

51. The method of controlling data transfer according to claim 35, wherein the switch system controls to deny reserving the storage target for the initiator, if the storage target is reserved for another initiator.

52. A method of controlling data transfer in a switch system coupled to an initiator and a plurality of disk array apparatuses, each of the disk array apparatuses comprising a disk controller and a plurality of disks, the method comprising:

receiving data of a first data write request, the first data write request being sent from the initiator for writing data to a storage area, as identified by identification information;

transferring the data of the first data write request to a first disk array apparatus of the disk array apparatuses so that the first disk array apparatus writes the data of the first data write request into at least a portion of the disks of the first disk array apparatus;

transferring data stored in the first disk array apparatus to a second disk array apparatus of the disk array apparatuses;

receiving data of a second data write request, the second data write request being sent from the initiator for writing data to the storage area;

transferring the data of the second data write request to the second disk array apparatus so that the second disk array apparatus writes the data of the second data write request into at least a portion of the disks of the second disk array apparatus; and

controlling to allow or deny reserving the storage area for another initiator based on whether or not the storage area is reserved for the initiator.

53. The method of controlling data transfer according to claim 52, wherein the switch system controls to allow or deny reserving the storage area for the another initiator during at least the transferring step for transferring data stored in the first disk array apparatus to the second disk array apparatus.

54. The method of controlling data transfer according to claim 52, wherein the switch system controls to allow or deny reserving the storage area for the another initiator based on a command, the command being used to request a reserve and being sent from the another initiator.

55. The method of controlling data transfer according to claim 52, wherein the switch system controls to allow reserving the storage area for the initiator and controls to release the storage area from the initiator.

56. The method of controlling data transfer according to claim 52, wherein the switch system controls to allow reserving the storage area for the initiator based on a first command sent from the initiator and controls to release the storage area from the initiator based on a second command sent from the initiator.

57. The method of controlling data transfer according to claim 52, wherein the switch system controls to allow or deny reserving the storage area for the another initiator based on a Reserve command of SCSI standards.

58. The method of controlling data transfer according to claim 52, wherein the storage area is a logical unit.

59. The method of controlling data transfer according to claim 52, wherein the controlling step, for controlling to allow or deny reserving the storage area for another initiator, is a control process controlling to allow or deny authorizing a reserve authority of the storage area to the another initiator based on whether or not the initiator is allowed authorizing the reserve of the storage area.

60. The method of controlling data transfer according to claim 52, wherein the switch system controls to deny reserving the storage area for another initiator, if the storage area is reserved for the initiator.

61. The method of controlling data transfer according to claim 52, wherein the switch system controls to transfer the data storage in the first disk array apparatus to the second disk array apparatus in a status in which the storage area is continuously accessed by the initiator.

62. The method of controlling data transfer according to claim 52, wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the storage area is continuously accessed by the initiator, the initiator being allowed reserving the storage area.

63. The method of controlling data transfer according to claim 52, wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the initiator does not need to change the definition of the storage area and tasks of the initiator can be performed continuously.

64. The method of controlling data transfer according to claim 52, wherein the storage area is a logical unit, and

wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the logical unit is continuously accessed by the initiator, the logical unit being reserved for the initiator.

65. The method of controlling data transfer according to claim 52, wherein the transferring step, for transferring the data stored in the first disk array apparatus to the second disk array apparatus, is executed by a data migration function in the switch system.

66. A switch system coupled to a initiator and a plurality of disk array apparatuses, each of the disk array apparatuses comprising a disk controller and a plurality of disks, the switch system comprising:

at least one first port coupled to the initiator;

at least one second port coupled to the disk array apparatuses; and

at least one controller controlling to allow or deny reserving a storage area, as identified by identification information, for another initiator based on whether or not the storage area is reserved for the initiator,

wherein the first port receives data of a first data write request, the first data write request being sent from the initiator for writing data to the storage area as identified by identification information,

wherein the second port transfers the data of the first data write request to a first disk array apparatus of the disk array apparatuses so that the first disk array apparatus writes the data of the first data write request into at least a portion of the disks of the first disk array apparatus,

wherein the second port transfers data stored in the first disk array apparatus to a second disk array apparatus of the disk array apparatuses,

wherein the first port receives data of a second data write request, the second data write request being sent from the initiator for writing data to the storage area, and

wherein the second port transfers the data of the second data write request to the second disk array apparatus so that the second disk array apparatus writes the data of the second data write request into at least a portion of the disks of the second disk array apparatus.

67. The switch system according to claim 66, wherein the controller controls to allow or deny reserving the storage area for the another initiator during that the second port transfers the data storage in the first disk array apparatus to the second disk array apparatus.

68. The switch system according to claim 66, wherein the controller controls to allow or deny reserving the storage area for the another initiator based on a command, the command being used to request a reserve and being sent from the another initiator.

69. The switch system according to claim 66, wherein the controller controls to allow reserving the storage area for the initiator and controls to release the storage area from the initiator.

70. A switch system coupled to a initiator and a plurality of disk array apparatuses, each of the disk array apparatuses comprising a disk controller and a plurality of disks, the switch system comprising:

at least one first port coupled to the initiator; and

at least one second port coupled to the disk array apparatuses;

wherein the first port receives data of a first data write request, the first data write request being sent from the initiator for writing data to a storage area as identified by identification information,

wherein the second port transfers the data of the first data write request to a first disk array apparatus of the disk array apparatuses so that the first disk array apparatus writes the data of the first data write request into at least a portion of the disks of the first disk array apparatus,

wherein the second port transfers data stored int he first disk array apparatus to a second disk array apparatus of the disk array apparatuses,

wherein the first port receives data of a second data write request, the second data write request being sent from the initiator for writing data to the storage area,

wherein the second port transfers the data of the second data write request to the second disk array apparatus so that the second disk array apparatus writes the data of the second data write request into at least a portion of the disks of the second disk array apparatus, and

wherein the switch system controls to deny reserving the storage area for another initiator, if the storage area is reserved for the initiator.

71. The switch system according to claim 70, wherein the switch system controls to allow reserving the storage area for the initiator based on a first command sent from the initiator and controls to release the storage area from the initiator based on a second command sent from the initiator.

72. The switch system according to claim 70, wherein the switch system controls to allow or deny reserving the storage area for the another initiator based on a Reserve command of SCSI standards.

73. The switch system according to claim 70, wherein the storage area is a logical unit.

74. The switch system according to claim 70, wherein the switch system controls to deny authorizing a reserve authority of the storage area to the another initiator based on that the initiator is authorized the reserve authority of the storage area, if the switch system controls to deny reserving the storage area for the another initiator.

75. The switch system according to claim 70, wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the storage area is continuously accessed by the initiator, the storage area being reserved for the initiator.

76. The switch system according to claim 70, wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the initiator does not need to change the definition of the storage area and tasks of the initiator can be performed continuously.

77. The switch system according to claim 70, wherein the storage area is a logical unit, and

wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the logical unit is continuously accessed by the initiator, the logical unit being reserved for the initiator.

78. The switch system according to claim 70, wherein the transferring process, for transferring the data stored in the first disk array apparatus to the second disk array apparatus, is executed by a data migration function in the switch system.

79. A switch system coupled to a initiator and a plurality of disk array apparatuses, each of the disk array apparatuses comprising a disk controller and a plurality of disks, the switch system comprising:

at least one first port coupled to the initiator;

at least one second port coupled to the disk array apparatuses; and

at least one reserve emulation control part controlling to allow or deny reserving a storage area, as identified by identification information, for the initiator,

wherein the first port receives data of a first data write request, the first data write request being sent from the initiator for writing data to the storage area as identified by identification information,

wherein the second port transfers the data of the first data write request to a first disk array apparatus of the disk array apparatuses so that the first disk array apparatus writes the data of the first data write request into at least a portion of the disks of the first disk array apparatus,

wherein the second port transfers data stored in the first disk array apparatus to a second disk array apparatus of the disk array apparatuses,

wherein the first port receives data of a second data write request, the second data write request being sent from the initiator for writing data to the storage area, and

wherein the second port transfers the data of the second data write request to the second disk array apparatus so that the second disk array apparatus writes the data of the second data write request into at least a portion of the disks of the second disk array apparatus.

80. The switch system of controlling data transfer according to claim 79, wherein the reserve emulation part controls to deny reserving the storage area for another initiator, if the storage area is reserved for the initiator.

81. The switch system of controlling data transfer according to claim 79, wherein the switch system controls to transfer the data stored in the first disk array apparatus to the second disk array apparatus in a status in which the storage area is continuously accessed by the initiator.