Method and apparatus for implementing a remote mirroring data facility without employing a dedicated leased line to form the link between two remotely disposed storage devices

• US 7,647,460 B1
• Filed: 09/23/1997
• Issued: 01/12/2010
• Est. Priority Date: 09/23/1997
• Status: Expired due to Term

• Current Assignee: EMC Corporation (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Wilson, Robert, Ting, Dennis P. J., Hosein, Mehamood
• Primary Examiner(s): CHACE, CHRISTIAN
• Application Number:
  US08/935,844
• Time in Patent Office: 4,494 Days
• Field of Search: 711/162, 711/161, 711/112, 711/113, 711/114, 364/187, 714 1- 4, 714/6, 714/7, 714/13, 714/11, 714/12, 709/203, 709/208, 709/217, 709/218, 709/219
• US Class Current: 711/162
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2066 Optimisation of the communication load
• CPC Class Codes: G06F 11/2071 using a plurality of controllers

Abstract

A method and apparatus for implementing a remote mirroring data facility for a computer system comprising a central processing unit (CPU); a first storage system that is coupled to the CPU so that the CPU can store information in the first storage system; a second storage system coupled to the CPU via a communication link; and a mirroring controller to mirror at least some of the information stored in the first storage system in the second storage system by transferring the at least some of the information over the communication link. The communication link can be implemented via a network cloud, which may be the Internet or an intranet. Multiple pipes can be used to pass data through the network cloud in parallel. Alternatively, the communication link can be implemented using wireless technology.

Claims

1. A computer system comprising:

a central processing unit (CPU);

a first storage system that is coupled to the CPU to store information written from the CPU;

a second storage system;

at least one communication link coupling the second storage system to the CPU, the at least one communication link including a network cloud that is shared with at least one other resource so that no portion of the network cloud is dedicated exclusively to transferring information between the CPU and the second storage system, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system; and

a mirroring controller, responsive to the information being written from the CPU to the first storage system, to mirror at least some of the information written from the CPU to the first storage system in the second storage system by transferring the at least some of the information through the network cloud.

2. The computer system of claim 1, wherein the network cloud includes the Internet, so that the network cloud is publicly accessible.

3. The computer system of claim 1, wherein the network cloud comprises an intranet.

4. The computer system of claim 1, wherein the at least one communication link is one of a packet switched network and a cell switched network.

5. The computer system of claim 1, wherein the CPU includes means for communicating with the at least one other resource via the network cloud.

6. The computer system of claim 1, wherein the at least one communication link includes a plurality of communication paths from the CPU to the network cloud, so that a plurality of packets of information can be transferred from the CPU to the second storage system in parallel through the network cloud.

7. The computer system of claim 6, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

8. The computer system of claim 1, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

9. The computer system of claim 1, wherein the at least one communication link includes at least one wireless connection.

10. The computer system of claim 1, wherein the mirroring controller is distributed between the first and second storage systems.

11. The computer system of claim 10, wherein the mirroring controller includes means, distributed between the first and second storage systems, for mirroring the at least some of the information written from the CPU to the first storage system in the second storage system.

12. The computer system of claim 11, wherein the CPU is a first CPU, and wherein the system further includes a second CPU coupled to the second storage system.

13. The computer system of claim 1, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system, and wherein the computer system further includes:

a third storage system coupled to the first storage system via the at least one communication link so that the CPU can store information in the third storage system via the first storage system; and

wherein the mirroring controller includes means, distributed between the first, second and third storage systems, for mirroring the at least some of the information written from the CPU to the first storage system in both of the second and third storage systems.

14. The computer system of claim 11, wherein the at least one communication link includes at least one wireless connection.

15. The computer system of claim 11, wherein the at least one communication link includes a plurality of communication paths from the CPU to the network cloud, so that a plurality of packets of information can be transferred from the CPU to the second storage system in parallel through the network cloud.

16. The computer system of claim 15, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

17. The computer system of claim 11, wherein the at least one communication link is one of a packet switched network and a cell switched network.

18. The computer system of claim 11, wherein the network cloud comprises an intranet.

19. The computer system of claim 11, wherein the network cloud includes the Internet, so that the network cloud is publicly accessible.

20. The computer system of claim 2, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

21. The computer system of claim 3, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

22. A computer system comprising:

a central processing unit (CPU);

a first storage system that is coupled to the CPU to store information written from the CPU;

a second storage system;

at least one communication link coupling the second storage system to the CPU, the at least one communication link including at least one wireless connection, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system;

a mirroring controller, responsive to the information being written from the CPU to the first storage system to mirror at least some of the information being written from the CPU to the first storage system in the second storage system by transferring the at least some of the information over the at least one communication link;

wherein the at least one communication link includes a network cloud that comprises an internet shared by at least one other resource.

23. A computer system comprising:

a central processing unit (CPU);

a first communication link;

a first storage system coupled to the CPU via the first communication link to store information written from the CPU;

a second storage system;

a second communication link coupling the second storage system to the CPU, wherein the second communication link extends between the first and second storage systems so that the second storage system is coupled to the CPU via the first storage system;

a third storage system;

a third communication link coupling the third storage system to the CPU, wherein the third communication link extends between the first and third storage systems so that the third storage system is coupled to the CPU via the first storage system; and

a mirroring controller, responsive to the information being written from the CPU to the first storage system, to mirror at least some of the information written from the CPU to the first storage system in both the second and third storage systems;

wherein the second and third communication links each comprises a network cloud that is shared by the first, second and third storage systems.

24. The computer system of claim 23, wherein the mirroring controller is distributed between the first, second and third storage systems.

25. The computer system of claim 23, wherein at least one of the second and third communication links is one of a packet switched network and a cell switched network.

26. The computer system of claim 23, further including means for multicasting the at least some of the information stored by the CPU in the first storage device to the second and third storage systems.

27. The computer system of claim 23, wherein the mirroring controller is distributed between the first and second storage systems.

28. A method of operating a computer system that includes a central processing unit (CPU), a first communication link, a first storage system coupled to the CPU via the first communication link to store information written from the CPU, a second storage system, a second communication link coupling the second storage system to the CPU and extending between the first and second storage systems so that the second storage system is coupled to the CPU via the first storage system, a third storage system, and a third communication link coupling the third storage system to the CPU and extending between the first and third storage systems so that the third storage system is coupled to the CPU via the first storage system, wherein each of the second and third communication links is formed through a network cloud that is shared by the first, second and third storage systems, the method comprising a step of:

(A) in response to the information being written from the CPU to the first storage system, mirroring at least some of the information written from the CPU to the first storage system in both the second and third storage systems by transferring the at least some of the information over the second and third communication links through the network cloud.

29. The method of claim 28, wherein step (A) includes a step of:

multicasting the at least some of the information stored by the CPU in the first storage device to the second and third storage systems over the network cloud.

30. A method of mirroring information stored in a computer system comprising a central processing unit (CPU), a first storage system that is coupled to the CPU to store information written from the CPU, and a second storage system coupled to the CPU by at least one communication link, the at least one communication link including a network cloud that is shared with at least one other resource so that no portion of the network cloud is dedicated exclusively to coupling the second storage system to the CPU, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system, the method comprising a step of:

A)—

in response to the information being written from the CPU to the first storage system, transmitting, from the first storage system, into the network cloud at least some of the information written from the CPU to the first storage system with the second storage system designated as a destination for the at least some of the information, so that the at least some of the information can be transferred through the network cloud and mirrored in the second storage system.

31. The method of claim 30, wherein the network cloud includes the Internet, and wherein step (A) includes a step of transmitting the at least some of the information into the Internet.

32. The method of claim 30, wherein the network cloud includes an intranet, and wherein step (A) includes a step of transmitting the at least some of the information into the intranet.

33. The method of claim 30, wherein the CPU is coupled to the network cloud through a plurality of communication paths;

and

wherein step (A) includes a step of transmitting a plurality of packets of the at least some of the information in parallel from the CPU to the network cloud.

34. The method of claim 33, wherein the second storage system is coupled to the network cloud through a plurality of communication paths;

and

wherein step (A) includes a step of transferring a plurality of packets of the at least some of the information in parallel from the network cloud to the second storage system.

35. The method of claim 30, wherein the second storage system is coupled to the network cloud through a plurality of communication paths;

and

wherein step (A) includes a step of transferring a plurality of packets of the at least some of the information in parallel from the network cloud to the second storage system.

36. The method of claim 30, wherein the computer system further includes a third storage system coupled to the CPU through the network cloud, and wherein the method further comprises a step of transmitting at least some of the information stored by the CPU in the first storage system into the network cloud with the third storage system designated as a destination for the at least some of the information, so that the at least some of the information can be transferred through the network cloud and mirrored in both the second and third storage systems.

37. The method of claim 30, further comprising a step of:

(B) storing the at least some of the information transferred through the network cloud in the second storage system.

38. A computer system capable of mirroring information in a remotely disposed target storage system that is coupled to the computer system via at least one communication link that includes a network cloud that is shared with at least one other resource, the computer system comprising:

a central processing unit (CPU) coupled to the network cloud;

a source storage system that is coupled to the CPU to store information written from the CPU, the source storage system to be coupled to the at least one communication link so that the at least one communication link extends between the source and target storage systems such that the CPU is coupled to the network cloud via the source storage system; and

a controller, responsive to the information being written from the CPU to the source storage system, to transfer at least some of the information written from the CPU into the network cloud so that the at least some of the information can be mirrored in the target storage system.

39. The computer system of claim 38, wherein the network cloud includes the Internet, so that the network cloud is publicly accessible.

40. The computer system of claim 38, wherein the network cloud comprises an intranet.

41. The computer system of claim 38, wherein the CPU is coupled to the network cloud through a plurality of communication paths so that a plurality of packets of information can be transferred from the CPU to the target storage system in parallel through the network cloud.

42. The computer system of claim 38, wherein the source storage system comprises the controller.

43. The computer system of claim 42, wherein the controller includes means, distributed between the source and target storage systems, for mirroring the at least some of the information stored in the source storage system in the target storage system.

44. A computer system comprising:

a central processing unit (CPU);

a first storage system that is coupled to the CPU to store information written from the CPU;

a second storage system;

at least one communication link coupling the second storage system to the CPU so that the CPU can store information in the second storage system, the at least one communication link being selected from the group consisting of an intranet and the Internet, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system; and

a mirroring controller, responsive to the information being written from the CPU to the first storage system, to mirror at least some of the information written from the CPU to the first storage system in the second storage system by transferring the at least some of the information over the at least one communication link.

45. The computer system of claim 44, wherein the mirroring controller is distributed between the first and second storage systems.

46. The computer system of claim 45, wherein the mirroring controller includes means, distributed between the first and second storage systems, for mirroring the at least some of the information stored in the first storage system in the second storage system.

47. A computer system comprising:

a central processing unit (CPU);

a first storage system that is coupled to the CPU to store information written from the CPU;

a second storage system;

at least one communication link coupling the second storage system to the CPU, the at least one communication link including a network cloud that is shared with at least one other resource so that no portion of the network cloud is dedicated exclusively to transferring information between the CPU and the second storage system, wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system, and wherein the at least one communication link includes a plurality of communication paths from the CPU to the network cloud, so that a plurality of packets of the information can be transferred from the CPU to the second storage system in parallel through the network cloud; and

a mirroring controller, responsive to the information being written from the CPU to the first storage system, to mirror at least some of the information written from the CPU to the first storage system in the second storage system by transferring the at least some of the information through the network cloud.

48. The computer system of claim 47, wherein the at least one communication link includes a plurality of communication paths from the network cloud to the second storage system, so that a plurality of packets of information can be transferred in parallel from the network cloud to the second storage system.

49. The computer system of claim 47, wherein the mirroring controller is distributed between the first and second storage systems.

50. A method of mirroring information stored in a computer system comprising a central processing unit (CPU), a first storage system that is coupled to the CPU to store information written from the CPU, and a second storage system coupled to the CPU by at least one communication link, the at least one communication link including a network cloud that is shared with at least one other resource so that no portion of the network cloud is dedicated exclusively to coupling the second storage system to the CPU, and wherein the at least one communication link extends between the first and second storage systems such that the second storage system is coupled to the CPU via the first storage system, the method comprising a step of:

A) in response to the information being written from the CPU to the first storage system, transmitting at least some of the information written from the CPU to the first storage system over at least two parallel paths into the network cloud with the second storage system designated as a destination for the at least some of the information, so that the at least some of the information can be transferred through the network cloud and mirrored in the second storage system.

51. A computer system capable of mirroring information in a remotely disposed target storage system that is coupled to the computer system via at least one communication link that includes a network cloud that is shared with at least one other resource, the computer system comprising:

a central processing unit (CPU) coupled to the network cloud; and

a source storage system that is coupled to the CPU to store information written from the CPU;

wherein the source storage system includes a controller, responsive to the information being written from the CPU to the source storage system, to transfer at least some of the information written from the CPU from the source storage system into the network cloud so that the at least some of the information can be mirrored in the target storage system, wherein the source storage system is coupled to the network cloud through a plurality of communication paths so that a plurality of packets of the information can be transferred from the source storage system to the target storage system in parallel through the network cloud.