Storage router and method for providing virtual local storage

• US 20060143322A1
• Filed: 02/14/2006
• Published: 06/29/2006
• Est. Priority Date: 12/31/1997
• Status: Active Grant

• Current Assignee: Crossroads Systems (Texas) Incorporated (Crossroads Systems, Inc.)
• Original Assignee: Crossroads Systems (Texas) Incorporated (Crossroads Systems, Inc.)
• Inventors: Russell, Jeffry T., Hoese, Geoffrey B.
• Granted Patent: US 7,340,549 B2
• Time in Patent Office: Days
• US Class Current: 710/8
• CPC Class Codes: G06F 13/1668 Details of memory controller
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: G06F 13/4022 using switching circuits, e.g. switching matrix, connection or expansion network G06F13/4009 takes precedence
• CPC Class Codes: G06F 13/4059 where the synchronisation uses buffers, e.g. for speed matching between buses
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0605 by facilitating the interaction with a user or administrator
• 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 3/0661 Format or protocol conversion arrangements
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• 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 3/0673 Single storage device
• CPC Class Codes: H04L 2101/631 Small computer system interface [SCSI] addresses
• CPC Class Codes: H04L 2101/645 Fibre channel identifiers
• CPC Class Codes: H04L 61/106 across networks, e.g. mapping telephone numbers to data network addresses
• 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 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

A storage router (56) and storage network (50) provide virtual local storage on remote SCSI storage devices (60, 62, 64) to Fibre Channel devices. A plurality of Fibre Channel devices, such as workstations (58), are connected to a Fibre Channel transport medium (52), and a plurality of SCSI storage devices (60, 62, 64) are connected to a SCSI bus transport medium (54). The storage router (56) interfaces between the Fibre Channel transport medium (52) and the SCSI bus transport medium (54). The storage router (56) maps between the workstations (58) and the SCSI storage devices (60, 62, 64) and implements access controls for storage space on the SCSI storage devices (60, 62, 64). The storage router (56) then allows access from the workstations (58) to the SCSI storage devices (60, 62, 64) using native low level, block protocol in accordance with the mapping and the access controls.

Claims

1-14. -14. (canceled)

15. A storage router for providing virtual local storage on storage devices to a host device, comprising:

a buffer providing memory work space for the storage router;

a first controller operable to connect to and interface with a first transport medium;

a second controller operable to connect to and interface with a second transport medium, wherein at least one of the first transport medium and the second transport medium is a serial transport medium; and

a supervisor unit coupled to the first and second controllers and the buffer, the supervisor unit operable to;

maintain a map that maps between the host device and at least a portion of a first storage device, the map comprising a representation of the host device and a representation of at least a portion of a first storage device; and

access the map to control access from devices connected to the first transport medium to the storage device to allow the host device to access the at least a portion of the first storage device through native low level block protocol.

16. The storage router of claim 15, wherein, for a request received from the host device according to a native low level block protocol, the supervisor unit is further operable to:

access the map to determine the appropriate storage space on the at least a portion of the first storage device using a host identification for the host device;

forward the request to the first storage device according to the native low level block protocol.

17. The storage router of claim 15, wherein the map further maps between the host device and at least a portion of a second storage device.

18. The storage router of claim 17, wherein the map further maps between at least one other host device and the at least a portion of the second storage device.

19. The storage router of claim 15, wherein the initiator devices comprise workstations.

20. The storage router of claim 15, wherein the storage devices comprise hard disk drives.

21. The storage router of claim 15, wherein the first controller comprises:

a protocol unit operable to connect to the transport medium;

a first-in-first-out queue coupled to the protocol unit; and

a direct memory access (DMA) interface coupled to the first-in-first-out queue and to the buffer.

22. The storage router of claim 21, wherein the second controller comprises:

a protocol unit operable to connect to the transport medium;

a first-in-first-out queue coupled to the protocol unit; and

a direct memory access (DMA) interface coupled to the first-in-first-out queue and to the buffer.

23. The storage router of claim 15, wherein the native low level block protocol is SCSI.

24. The storage router of claim 23, wherein the SCSI native low level block protocol is encapsulated in a Fibre Channel transport protocol on the first transport medium.

25. The storage router of claim 23, wherein the SCSI native low level block protocol is encapsulated in a Fibre Channel transport protocol on the second transport medium.

26. The storage router of claim 23, wherein the SCSI native low level block protocol is encapsulated in an iSCSI transport protocol on the first transport medium.

27. The storage router of claim 23, wherein the SCSI native low level block protocol is encapsulated in an iSCSI transport protocol on the second transport medium.

28. The storage router of claim 15, wherein the native low level block protocol is ATA.

29. The storage router of claim 28, wherein the ATA native low level block protocol is encapsulated in a Fibre Channel transport protocol on the first transport medium.

30. The storage router of claim 28, wherein the ATA native low level block protocol is encapsulated in a Fibre Channel transport protocol on the second transport medium.

31. The storage router of claim 28, wherein the ATA native low level block protocol is encapsulated in an iSCSI transport protocol on the first transport medium.

32. The storage router of claim 28, wherein the ATA native low level block protocol is encapsulated in an ISCSI transport protocol on the second transport medium.

33. The storage router of claim 15, wherein the supervisor unit further comprises a processor.

34. The storage router of claim 33, wherein the processor comprises one of an ASIC, microprocessor, CPU, microcontroller or DSP.

35. The storage router of claim 15, wherein the supervisor unit maintains an allocation of subsets of storage space to associated host devices connected to the first transport medium, wherein each subset is only accessible by the associated host device connected to the first transport medium.

36. The storage router of claim 15, wherein, for the host device, the map maps from a host identification for the host device to a physical address for the at least a portion of the first storage device.

37. The storage router of claim 15, wherein, for the host device, the map maps from the host identification for the host device to a virtual address for the at least a portion of the first storage device to a physical address for the at least a portion of the first storage device.

64. The storage router of claim 15, wherein, for the first host device connected to the first transport medium, the map maps from the first host identification to a virtual address an associated subset of storage to a physical address for the associated subset of storage.

38. A storage router for providing virtual local storage on storage devices to a host device, comprising:

a buffer providing memory work space for the storage router;

a first controller operable to connect to and interface with a first transport medium;

a second controller operable to connect to and interface with a second transport medium, wherein at least one of the first transport medium and the second transport medium is a serial transport medium; and

a supervisor unit coupled to the first and second controllers and the buffer, the supervisor unit operable to;

maintain a map that comprises host identifications for devices on the first transport medium and representations of at least a portion of a storage device on the second transport medium, the map associating subsets of storage space on the storage devices connected to the second transport medium with the devices connected to the first transport medium; and

for a request received from a first host, access the map to determine the storage space associated with a first host using the host identification for the first host to direct the request to the appropriate subset of storage space, wherein the request is received from the first host and forwarded to the storage device containing the storage space through a native low level block protocol.

39. The storage router of claim 38, wherein a particular subset of storage space comprises a single storage device, storage on multiple storage devices, a portion of a single storage device or portions of storage on multiple storage devices.

40. The storage router of claim 38, wherein at least one subset of storage space is associated with multiple devices connected to the first transport medium.

41. The storage router of claim 38, wherein the map further defines global storage available to any host device on the first transport medium.

42. The storage router of claim 41, wherein a device on the first transport medium not represented in the map is allowed access to the global storage.

43. The storage router of claim 38, wherein each subset of storage space is only accessible by devices on the first transport medium associated with that subset of storage space in the map.

44. The storage router of claim 38, wherein the supervisor unit is further operable to direct requests to a same address from different devices on the first transport medium to different associated subsets of storage based on the map.

45. The storage router of claim 38, wherein at least one subset of storage is accessible by at least two hosts.

46. The storage router of claim 38, wherein the devices connected to the first transport medium comprise workstations.

47. The storage router of claim 38, wherein the storage devices comprise hard disk drives.

48. The storage router of claim 38, wherein the first controller comprises:

a protocol unit operable to connect to the transport medium;

a first-in-first-out queue coupled to the protocol unit; and

a direct memory access (DMA) interface coupled to the first-in-first-out queue and to the buffer.

49. The storage router of claim 48, wherein the second controller comprises:

a protocol unit operable to connect to the transport medium;

a first-in-first-out queue coupled to the protocol unit; and

a direct memory access (DMA) interface coupled to the first-in-first-out queue and to the buffer.

50. The storage router of claim 38, wherein the native low level block protocol is SCSI.

51. The storage router of claim 50, wherein the SCSI native low level block protocol is encapsulated in a Fibre Channel transport protocol on the first transport medium.

52. The storage router of claim 50, wherein the SCSI native low level block protocol is encapsulated in a Fibre Channel transport protocol on the second transport medium.

53. The storage router of claim 50, wherein the SCSI native low level block protocol is encapsulated in an iSCSI transport protocol on the first transport medium.

54. The storage router of claim 50, wherein the SCSI native low level block protocol is encapsulated in an iSCSI transport protocol on the second transport medium.

55. The storage router of claim 38, wherein the native low level block protocol is ATA.

56. The storage router of claim 55, wherein the ATA native low level block protocol is encapsulated in a Fibre Channel transport protocol on the first transport medium.

57. The storage router of claim 55, wherein the ATA native low level block protocol is encapsulated in a Fibre Channel transport protocol on the second transport medium.

58. The storage router of claim 55, wherein the ATA native low level block protocol is encapsulated in an iSCSI transport protocol on the first transport medium.

59. The storage router of claim 55, wherein the ATA native low level block protocol is encapsulated in an iSCSI transport protocol on the second transport medium.

60. The storage router of claim 38, wherein the supervisor unit further comprises a processor.

61. The storage router of claim 60, wherein the processor comprises one of an ASIC, microprocessor, CPU, microcontroller or DSP.

63. The storage router of claim 38, wherein, for the first host device connected to the first transport medium, the map maps from the first host identification to a physical address corresponding to an associated subset of storage.