Method and apparatus for provisioning storage resources

• US 7,945,669 B2
• Filed: 10/30/2002
• Issued: 05/17/2011
• Est. Priority Date: 10/30/2002
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Alexander, Jeffrey L., Lowenthal, Sheldon, Lindholm, Jason D., Bober, Paul M.
• Primary Examiner(s): Avellino; Joseph E
• Assistant Examiner(s): Duong; Thomas
• Application Number:
  US10/283,908
• Publication Number:
  US 20040088417A1
• Time in Patent Office: 3,121 Days
• Field of Search: 709217-219, 709/225, 709227-229, 709/226
• US Class Current: 709/226
• 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: H04L 69/329 in the application layer [OSI layer 7]

Abstract

A method and apparatus for automatically provisioning at least a portion of a computer system to meet a specification provided in a provisioning request. In one embodiment, the provisioning includes provisioning at least one resource from each of at least one host computer, at least one storage system, and at least one connectivity resource that connects the at least one host computer to the at least one storage system. In another embodiment, the provisioning includes selecting and configuring at least one logical volume of storage and configuring the computer system to provide access to the selected volume. In another aspect, a computer-readable provisioning transaction is created to provision the computer system, and a computer-readable undo transaction is created to undo it. In a further embodiment, an existing computer system is reverse engineered to create a specification that is modified to create the specification in the provisioning request.

Claims

1. A method, of provisioning at least a portion of a computer system to meet a specification provided in a provisioning request, the method comprising:

reading the provisioning request, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one or more storage elements; and

automatically provisioning the at least a portion of the computer system to meet the specification provided in the provisioning request, including automatically provisioning at least one-resource from at least one host computer, at least one resource from at least one storage system, and at least one resource from at least one connectivity resource that connects the at least one host computer to the at least one storage system, wherein the provisioning request specifies a provisioning preference and said automatically provisioning attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, said automatically provisioning includes processing to implement the provisioning request without satisfying the provisioning preference, wherein said automatically provisioning further includes performing first processing, said first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the first set also satisfies the requirements relating to a logical association, and wherein if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.

2. The method of claim 1, wherein each of the at least one host computer, the at least one storage system and the at least one connectivity resource comprises a plurality of resources, and wherein the said automatically provisioning further comprising:

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource to identify selected resources to satisfy the provisioning request;

creating a transaction that comprises a series of actions to configure the selected resources to satisfy the provisioning request; and

executing the transaction to configure the selected resources in a manner that satisfies the provisioning request.

3. The method of claim 2, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, the at least one entity including at least one of a file system, a logical volume manager and a database manager, and wherein said creating a transaction comprises creating a transaction that allocates at least one of the logical volumes to the at least one entity in the at least one host computer.

4. The method of claim 2, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, and wherein said creating a transaction comprises creating a transaction that assigns at least one of the logical volumes to at least one port of the at least one host computer through which the at least one of the logical volumes will be accessible to the at least one entity.

5. The method of claim 2, wherein said selecting the at least one resource comprises selecting at least one logical volume of storage, presented by the at least one storage system, to be used by the at least one host computer to store information to satisfy the provisioning request.

6. The method of claim 5, wherein said creating a transaction comprises creating a transaction that configures the selected at least one logical volume to satisfy the provisioning request.

7. The method of claim 6, wherein said creating a transaction comprises creating a transaction that configures the selected at least one logical volume to serve as a spare volume available for dynamic assignment.

8. The method of claim 5, wherein said selecting the at least one resource comprises considering performance characteristics of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

9. The method of claim 5, wherein said selecting the at least one resource comprises considering a storage capacity of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

10. The method of claim 2, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that maps at least one of the logical volumes to at least one port of the at least one storage system through which the at least one of the logical volumes will be accessible.

11. The method of claim 10, wherein the at least one storage system has an existing configuration prior to said automatically provisioning in which the at least one of the logical volumes is mapped to a first port of the at least one storage system, and wherein said creating a transaction comprises creating a transaction that re-maps the at least one of the logical volumes to a second port of the at least one storage system that is different than the first port.

12. The method of claim 2, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that creates a mirrored relationship between at least two of the logical volumes.

13. The method of claim 2, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that configures a communication path through the at least one connectivity resource to make at least one of the logical volumes accessible to the at least one host computer to store information.

14. The method of claim 13, wherein said creating a transaction comprises creating a transaction that configures at least two parallel communication paths through the at least one connectivity resource to make the at least one of the logical volumes accessible to the at least one host computer.

15. The method of claim 2, wherein the at least one host computer comprises a plurality of host computers, wherein the at least one storage system presents logical volumes of storage usable by the plurality of host computers to store information, and wherein said creating a transaction comprises creating a transaction that zones the computer system to provide access to at least one of the logical volumes only to a subset of the plurality of host computers.

16. The method of claim 15, wherein the computer system has an existing configuration, prior to said automatically provisioning, in which the computer system is zoned to provide access to the at least one of the logical volumes to a first subset of the plurality of host computers, and wherein said creating a transaction comprises creating a transaction that re-zones the computer system to provide access to the at least one of the logical volumes only to a second subset of the plurality of host computers that is different than the first subset.

17. The method of claim 2, wherein said selecting the at least one resource comprises:

determining what resources are available for selection to satisfy the provisioning request by querying the at least one host, computer, the at least one storage system and the at least one connectivity resource; and

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource in response to the act of determining.

18. The method of claim 2, wherein the computer system comprises at least one data set that comprises information relating to resources, available from at least one of the at least one host computer, the at least one storage system and the at least one connectivity resource, and wherein said selecting the at least one resource comprises:

determining what resources are available to satisfy the provisioning request by querying the data set; and

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource in response to the act of determining.

19. The method of claim 2, further comprising undoing at least some of the series of actions performed when executing the transaction.

20. The method of claim 19, wherein said undoing at least some of the actions comprises:

creating an undo transaction that comprises a series of undo actions that undo the series of actions created in said creating a transaction; and

executing at least some of the series of undo actions.

21. The method of claim 1, further comprising performing, prior to said reading and said automatically provisioning:

creating the provisioning request.

22. The method of claim 21, wherein said creating the provisioning request further comprises:

reverse engineering an existing computer system to create a specification of a configuration of the existing computer system; and

modifying the specification of the existing computer system to create the specification provided in the provisioning request.

23. The method of claim 22, wherein said creating the provisioning request is a computer-implemented.

24. The method of claim 1, wherein the at least one connectivity resource comprises at least one network resource that forms at least part of a network interconnecting the at least one host computer and the at least one storage system, and wherein said automatically provisioning further comprises automatically provisioning the at least one network resource.

25. The method of claim 1, wherein the at least one storage system presents a plurality of logical volumes of storage usable by at least one entity in the at least one host computer to store information, wherein the computer system has an existing configuration, prior to said automatically provisioning, in which at least some of the plurality of logical volumes presented by the at least one storage system is allocated to an entity in the at least one host computer, and wherein the method further comprises performing, prior to executing a transaction that allocates one of the plurality of logical volumes, determining that the one of the plurality of logical volumes is not already assigned to a different entity in the at least one host computer:

26. The method of claim 1, wherein if the provisioning request specifies an absolute provisioning requirement, an error is returned in response to the provisioning request if said automatically provisioning is unable to implement the provisioning request in accordance with the absolute provisioning requirement.

27. The method of claim 1, wherein the provisioning request includes at least one of host-based information, storage system-based information and connectivity information, said host-based information specifying how the at least one resource from the at least one storage system will be used by the at least one host computer, said storage system-based information specifying at least one aspect affecting selection of the at least one resource from the at least one storage system, said connectivity information specifying at least one aspect affecting selection of the at least one connectivity resource, and wherein said automatically provisioning automatically performs processing to determine one or more aspects of provisioning not specified in the provisioning request.

28. The method of claim 1, wherein the provisioning request includes host-based information, storage system-based information and connectivity information, said host-based information specifying how the at least one resource from the at least one storage system will be used by the at least one host computer, said storage system-based information specifying at least one aspect affecting selection of the at least one resource from the at least one storage system, said connectivity information specifying at least one aspect affecting selection of the at least one connectivity resource, and wherein said automatically provisioning automatically performs processing to determine one or more aspects of provisioning not specified in the provisioning request.

29. The method of claim 28, wherein said connectivity information includes information for at least one of:

identifying one or more logical storage volumes of the at least one storage system to be accessible using a specified port of a host computer, specifying multiple paths over which a single host can access a set of one or more logical storage volumes of the at least one storage system, and a mapping of a logical storage volume of the at least one storage system to one or more ports of the at least one storage system.

30. The method of claim 1, wherein if the provisioning request includes first information specifying a first level of detail regarding any of the at least one resource from the at least one storage system and the at least one connectivity resource for use in connection with provisioning, said automatically provisioning is performed using the first information, and otherwise, if the provisioning request does not include the first information, specification of the first level of detail is performed automatically in processing comprising said automatically provisioning.

31. The method of claim 30, wherein the first information of the provisioning request includes information regarding the at least one connectivity resource identifying a mapping of a first logical volume to a port of a storage system and identifying which one or more ports of a host computer have accessibility to the first logical volume.

32. A non-transitory computer readable storage medium encoded with a computer program that, when executed, performs a method of provisioning at least a portion of a computer system to meet a specification provided in a provisioning request, the method comprising:

reading the provisioning request, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one or more storage elements; and

automatically provisioning the at least a portion of the computer system to meet the specification provided in the provisioning request, including automatically provisioning at least one resource from at least one host computer, at least one resource from at least one storage system, and at least one resource from at least one connectivity resource that connects the at least one host computer to the at least one storage system, wherein the provisioning request specifies a provisioning preference and said automatically provisioning attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, said automatically provisioning includes processing to implement the provisioning request without satisfying the provisioning preference, wherein said automatically provisioning further includes performing first processing, said first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the first set also satisfies the requirements relating to a logical association, and wherein if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.

33. The non-transitory computer readable storage medium of claim 32, wherein each of the at least one host computer, the at least one storage system and the at least one connectivity resource comprises a plurality of resources, and wherein said automatically provisioning comprises:

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the least one storage system and the at least one connectivity resource to identify selected resources to satisfy the provisioning request;

creating a transaction that comprises a series of actions to configure the selected resources to satisfy the provisioning request; and

executing the transaction to configure the selected resources in a manner that satisfies the provisioning request.

34. The non-transitory computer readable storage medium of claim 33, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, the at least one entity including at least one of a file system, a logical volume manager and a database manager, and wherein said creating a transaction comprises creating a transaction that allocates at least one of the logical volumes to the at least one entity in the at least one host computer.

35. The non-transitory computer readable storage medium of claim 33, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, and wherein said creating a transaction comprises creating a transaction that assigns at least one of the logical volumes to at least one port of the at least one host computer through which the at least one of the logical volumes will be accessible to the at least one entity.

36. The non-transitory computer readable storage medium of claim 33, wherein said selecting the at least one resource comprises selecting at least one logical volume of storage, presented by the at least one storage system, to be used by the at least one host computer to store information to satisfy the provisioning request.

37. The non-transitory computer readable storage medium of claim 36, wherein said creating a transaction comprises creating a transaction that configures the selected at least one logical volume to satisfy the provisioning request.

38. The non-transitory computer readable storage medium of claim 37, wherein said creating a transaction comprises creating a transaction that configures the selected at least one logical volume to serve as a spare volume available for dynamic assignment.

39. The non-transitory computer readable storage medium of claim 36, wherein said selecting the at least one resource comprises considering performance characteristics of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

40. The non-transitory computer readable storage medium of claim 36, wherein said selecting the at least one resource comprises considering a storage capacity of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

41. The non-transitory computer readable storage medium of claim 33, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that maps at least one of the logical volumes to at least one port of the at least one storage system through which the at least one of the logical volumes will be accessible.

42. The non-transitory computer readable storage medium of claim 41, wherein the at least one storage system has an existing configuration prior to performing said automatically provisioning in which the at least one of the logical volumes is mapped to a first port of the at least one storage system, and wherein said creating a transaction comprises creating a transaction that re-maps the at least one of the logical volumes to a second port of the at least one storage system that is different than the first port.

43. The non-transitory computer readable storage medium of claim 33, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that creates a mirrored relationship between at least two of the logical volumes.

44. The non-transitory computer readable storage medium of claim 33, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein said creating a transaction comprises creating a transaction that configures a communication path through the at least one connectivity resource to make at least one of the logical, volumes accessible to the at least one host computer to store information.

45. The non-transitory computer readable storage medium of claim 44, wherein said creating a transaction comprises creating a transaction that configures at least two parallel communication paths through the at least one connectivity resource to make the at least one of the logical volumes accessible to the at least one host computer.

46. The non-transitory computer readable storage medium of claim 33, wherein the at least one host computer comprises a plurality of host computers, wherein the at least one storage system presents logical volumes of storage usable by the plurality of host computers to store information, and wherein said creating a transaction comprises creating a transaction that zones the computer system to provide access to at least one of the logical volumes only to a subset of the plurality of host computers.

47. The non-transitory computer readable storage medium of claim 46, wherein the computer system has an existing configuration, prior to performing said automatically provisioning, in which the computer system is zoned to provide access to the at least one of the logical volumes to a first subset of the plurality of host computers, and wherein said creating a transaction comprises creating a transaction that re-zones the computer system to provide access to the at least one of the logical volumes only to a second subset of the plurality of host computers that is different than the first subset.

48. The non-transitory computer readable storage medium of claim 33, wherein said selecting the at least one resource comprises:

determining what resources are available for selection to satisfy the provisioning request by querying the at least one host computer, the at least one storage system and the at least one connectivity resource; and

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource in response to the act of determining.

49. The non-transitory computer readable storage medium of claim 33, wherein the computer system comprises at least one data set that comprises information relating to resources available from at least one of the at least one host computer, the at least one storage system and the at least one connectivity resource, and wherein said selecting the at least one resource comprises:

determining what resources are available to satisfy the provisioning request by querying the data set; and

selecting the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource in response to the act of determining.

50. The non-transitory computer readable storage medium of claim 33, wherein the method further comprises undoing at least some of the series of actions performed when executing the transaction.

51. The non-transitory computer readable storage medium of claim 50, wherein said undoing at last some actions comprises:

creating an undo transaction that comprises a series of undo actions that undo the series of actions created in said step of creating a transaction; and

executing at least some of the series of undo actions.

52. The non-transitory computer readable storage medium of claim 32, wherein the method further comprises performing, prior to said reading and said automatically provisioning:

assisting in creating the provisioning request.

53. The non-transitory computer readable storage medium of claim 52, wherein said assisting comprises:

reverse engineering an existing computer system to create a specification of a configuration of the existing computer system.

54. The non-transitory computer readable storage medium of claim 53, wherein said reverse engineering is a computer-implemented act.

55. The non-transitory computer readable storage medium of claim 32, wherein the at least one connectivity resource comprises at least one network resource that forms at least part of a network interconnecting the at least one host computer and the at least one storage system, and wherein said automatically provisioning comprises automatically provisioning the at least one network resource.

56. The non-transitory computer readable storage medium of claim 32, wherein the at least one storage system presents a plurality of logical volumes of storage usable by at least one entity in the at least one host computer to store information, wherein the computer system has an existing configuration, prior to performing said automatically provisioning, in which at least some of the plurality of logical volumes presented by the at least one storage system are allocated to an entity in the at least one host computer, and wherein the method further comprises, prior to executing a transaction that allocates one of the plurality of logical volumes, determining that the one of the plurality of logical volumes is not already assigned to a different entity in the at least one host computer.

57. An apparatus, comprising:

at least one processor programmed to automatically provision at least a portion of a computer system to meet a specification provided in a provisioning request, including automatically provisioning at least one resource from at least one host computer, at least one resource from at least one storage system, and at least one resource from at least one connectivity resource that connects the at least one host computer to the at least one storage system, wherein the provisioning request specifies a provisioning preference and the at least one processor is programmed to perform processing which attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, the at least one processor is programmed to perform processing to implement the provisioning request without satisfying the provisioning preference, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one Or more storage elements, and wherein said automatically provisioning includes performing first processing, said first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the set also satisfies the requirements relating to a logical association, and wherein if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.

58. The apparatus of claim 57, wherein each of the at least one host computer, the at least one storage system and the at least one connectivity resource comprises a plurality of resources, and wherein the at least one processor is programmed to:

select the at least one resource from among the plurality of resources for each of the at least one host computer, the at least one storage system and the at least one connectivity resource to identify selected resources to satisfy the provisioning request;

create a transaction that comprises a series of actions to configure the selected resources to satisfy the provisioning request; and

execute the transaction to configure the selected resources in a manner that satisfies the provisioning request.

59. The apparatus of claim 58, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, the at least one entity including at least one of a file system, a logical volume manager and a database manager, and wherein the at least one processor is programmed to create a transaction that allocates at least one of the logical volumes to the at least one entity in the at least one host computer.

60. The apparatus of claim 58, wherein the at least one storage system presents logical volumes of storage usable by at least one entity in the at least one host computer to store information, and wherein the at least one processor is programmed to create a transaction that assigns at least one of the logical volumes to at least one port of the at least one host computer through which the at least one of the logical volumes will be accessible to the at least one entity.

61. The apparatus of claim 58, wherein the at least one processor is programmed to select at least one logical volume of storage, presented by the at least one storage system, to be used by the at least one host computer to store information to satisfy the provisioning request.

62. The apparatus of claim 61, wherein the at least one processor is programmed to create a transaction that configures the selected at least one logical volume to satisfy the provisioning request.

63. The apparatus of claim 62, wherein the at least one processor is programmed to create a transaction that configures the selected at least one logical volume to serve as a spare volume available for dynamic assignment.

64. The apparatus of claim 61, wherein the at least one processor is programmed to consider performance characteristics of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

65. The apparatus of claim 61, wherein the at least one processor is programmed to consider a storage capacity of the at least one logical volume in determining that the selected at least one logical volume can be used to satisfy the provisioning request.

66. The apparatus of claim 58, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein the at least one processor it programmed to create a transaction that maps at least one of the logical volumes to at least one port of the at least one storage system through which the at least one of the logical volumes will be accessible.

67. The apparatus of claim 66, wherein the at least one storage system has an existing configuration, prior to execution of the transaction, in which the at least one of the logical volumes is mapped to a first port of the at least one storage system, and wherein the at least one processor is programmed to create and execute a transaction that re-maps the at least one of the logical volumes to a second port of the at least one storage system that is different than the first port.

68. The apparatus of claim 58, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein the at least one processor is programmed to create a transaction that creates a mirrored relationship between at least two of the logical volumes.

69. The apparatus of claim 58, wherein the at least one storage system presents logical volumes of storage that can be used to store information, and wherein the at least one processor is programmed to create a transaction that configures a communication path through the at least one connectivity resource to make at least one of the logical volumes accessible to the at least one host computer to store information.

70. The apparatus of claim 69, wherein the at least one processor is programmed to create a transaction that configures at least two parallel communication paths through the at least one connectivity resource to make the at least one of the logical volumes accessible to the at least one host computer.

71. The apparatus of claim 58, wherein the at least one host computer comprises a plurality of host computers, wherein the at least one storage system presents logical volumes of storage usable by the plurality of host computers to store information, and wherein the at least one processor is programmed to create a transaction that zones the computer system to provide access to at least one of the logical volumes only to a subset of the plurality of host computers.

72. The apparatus of claim 71, wherein the computer system has an existing configuration, prior to execution of the transaction, in which the computer system is zoned to provide access to the at least one of the logical volumes to a first subset of the plurality of host computers, and wherein the at least one processor is programmed to create and execute a transaction that re-zones the computer system to provide access to the at least one of the logical volumes only to a second subset of the plurality of host computers that is different than the first subset.

73. The apparatus of claim 58, wherein the at least one processor is programmed to:

determine what resources are available for selection to satisfy the provisioning request by querying the at least one host computer, the at least one storage system and the at least one connectivity resource; and

select the at least one resource from among the plurality of resources determined to be available for each of the at least one host computer, the at least one storage system and the at least one connectivity resource.

74. The apparatus of claim 58, wherein the computer system comprises at least one data set that comprises information relating to resources available from at least one of the at least one host computer, the at least one storage system and the at least one connectivity resource, and wherein the at least one processor is programmed to:

determine what resources are available to satisfy the provisioning request by querying the data set; and

select the at least one resource from among the plurality of resources determined to be available for each of the at least one host computer, the at least one storage system and the at least one connectivity resource.

75. The apparatus of claim 58, wherein the at least one processor is programmed to undo at least some of the series of actions executed when the transaction is executed.

76. The apparatus of claim 75, wherein the at least one processor is programmed to create an undo transaction that comprises a series of undo actions that undo the series of actions in the transaction.

77. The apparatus of claim 57, wherein the processor is programmed to assist in creating the provisioning request.

78. The apparatus of claim 77, wherein the at least one processor is programmed to assist in creating the provisioning request by reverse engineering an existing computer system to create a specification of a configuration of the existing computer system, so that the specification of the existing computer system can be modified to create the specification provided in the provisioning request.

79. The apparatus of claim 57, wherein the at least one connectivity resource comprises at least one network resource that forms at least part of network interconnecting the at least one host computer and the at least one storage system, and wherein the at least one processor is programmed to automatically provision the at least one network resource.

80. The apparatus of claim 57, wherein the at least one storage system presents a plurality of logical volumes of storage usable by at least one entity in the at least one host computer to store information, wherein the computer system has an existing configuration, prior to execution of the transaction, in which at least some of the plurality of logical volumes presented by the at least one storage system are allocated to an entity in the at least one host computer, and wherein the at least one processor is programmed to, prior to executing a transaction that allocates one of the plurality of logical volumes, determine that the one of the plurality of logical volumes is not already assigned to a different entity in the at least one host computer.

81. The apparatus of claim 57, wherein the provisioning request specifies provisioning requirements in any of a plurality of levels of detail and wherein the apparatus further comprises a computer readable storage medium including code stored thereon to process each of said plurality of levels of detail.

82. A method of provisioning at least a portion of a computer system to meet a specification provided in a provisioning request, the method comprising:

reading the provisioning request, the provisioning request defining the at least a portion of the computer system to comprise a unit of storage to be provided to at least one of a plurality of host computers, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one or more storage elements;

automatically provisioning the at least a portion of the computer system in response to the provisioning request, including;

selecting at least one logical volume of storage from at least one storage system that can serve as the unit of storage defined by the provisioning request;

selecting at least one connectivity resource that can provide a communication path through which the selected at least one logical volume can be made accessible to the at least one of the plurality of host computers;

creating a transaction that comprises a series of actions to configure the selected at least one logical volume and the selected at least one connectivity resource to satisfy the provisioning request, including configuring the selected at least one logical volume to satisfy the provisioning request, mapping the selected at least one logical volume to at least one port of the at least one storage system through which the selected at least one logical volume will be accessible, configuring the communication path, and configuring the at least a portion of the computer system to provide access to the selected at least one logical volume only to the at least one of the plurality of host computers; and

executing the transaction to configure the selected at least one logical volume and the selected at least one connectivity resource in a manner that satisfies the provisioning request, and wherein the provisioning request specifies a provisioning preference and said automatically provisioning attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, said automatically provisioning includes processing to implement the provisioning request without satisfying the provisioning preference, and

wherein said automatically provisioning includes performing first processing, said first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the first set also satisfies the requirements relating to a logical association, and if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.

83. The method of claim 82, wherein the provisioning request indicates a level of tolerance for automatically reconfiguring one or more volumes of storage having an existing storage configuration in order to satisfy the provisioning request.

84. The method of claim 83, wherein, if the provisioning request specifies a first level of tolerance indicating no tolerance for reconfiguration operations, said automatically provisioning is prevented from changing a current configuration of any existing volumes of storage in order to satisfy the provisioning request, and if the provisioning request specifies a second level of tolerance higher than the first level, said automatically provisioning is authorized to change a current configuration of one or more existing volumes of storage in order to satisfy the provisioning request.

85. A non-transitory computer readable storage medium encoded with a computer program that, when executed, performs a method of provisioning at least a portion of a computer system to meet a specification provided in a provisioning request, the method comprising:

reading the provisioning request, the provisioning request defining the at least a portion of the computer system to comprise a unit of storage to be provided to at least one of a plurality of host computers, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one or more storage elements;

automatically provisioning the at least a portion of the computer system in response to the provisioning request, including;

selecting at least one logical volume of storage from at least one storage system that can serve as the unit of storage defined by the provisioning request;

selecting at least one connectivity resource that can provide a communication path through which the selected at least one logical volume can be made accessible to the at least one of the plurality of host computers;

creating a transaction that comprises a series of actions to configure the selected at least one logical volume and the selected at least one connectivity resource to satisfy the provisioning request, including configuring the selected at least one logical volume to satisfy the provisioning request, mapping the selected at least one logical volume to at least one port of the at least one storage system through which the selected at least one logical volume will be accessible, configuring the communication path, and configuring the at least a portion of the computer system to provide access to the selected at least one logical volume only to the at least one of the plurality of host computers; and

executing the transaction to configure the selected at least one logical volume and the selected at least one connectivity resource in a manner that satisfies the provisioning request, and wherein the provisioning request specifies a provisioning preference and said automatically provisioning attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, said automatically provisioning includes processing to implement the provisioning request without satisfying the provisioning preference, and wherein

said automatically provisioning further includes performing first processing, said first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the first set also satisfies the requirements relating to a logical association, and if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.

86. An apparatus, comprising:

at least one processor programmed to automatically provision at least a portion of a computer system to meet a specification provided in a provisioning request that defines the at least a portion of the computer system to comprise a unit of storage to be provided to at least one of a plurality of host computers, wherein the provisioning request includes physical requirements for one or more storage elements and requirements relating to a logical association of the one or more storage elements, the at least one processor being programmed to;

select at least one logical volume of storage from at least one storage system that can serve as the unit of storage defined by the provisioning request;

select at least one connectivity resource that can provide a communication path through which the selected at least one logical volume can be made accessible to the at least one of the plurality of host computers;

create a transaction that comprises a series of actions to configure the selected at least one logical volume and the selected at least one connectivity resource to satisfy the provisioning request, including configuring the selected at least one logical volume to satisfy the provisioning request, mapping the selected at least one logical volume to at least one port of the at least one storage system through which the selected at least one logical volume will be accessible, configuring the communication path, and configuring the at least a portion of the computer system to provide access to the selected at least one logical volume only to the at least one of the plurality of host computers; and

execute the transaction to configure the selected at least one logical volume and the selected at least one connectivity resource in a manner that satisfies the provisioning request, and wherein the provisioning request specifies a provisioning preference and the at least one processor is programmed to perform processing which attempts to implement the provisioning request satisfying the provisioning preference, and if unable to implement the provisioning request and satisfy the provisioning preference, the at least one processor is programmed to perform processing to implement the provisioning request without satisfying the provisioning preference, and

wherein the at least one processor is further programmed to perform first processing including;

selecting a set of one or more resources;

determining whether the set satisfies the physical requirements, wherein if it is determined that the set does not satisfy the physical requirements, the physical requirements are modified, another set of one or more resources is selected, and it is determined whether the another set satisfies the modified physical requirements; and

wherein, after a first set of resources is determined that satisfies the physical requirements or a modified set of the physical requirements, it is determined whether the first set also satisfies the requirements relating to a logical association, and if it is determined that the first set does not satisfy the requirements relating to a logical association, any of the physical requirements and the requirements relating to a logical association are modified, and additional processing is performed to select resources satisfying the provisioning request.