Storage router and method for providing virtual local storage

• US 6,738,854 B2
• Filed: 06/19/2002
• Issued: 05/18/2004
• Est. Priority Date: 12/31/1997
• Status: Expired due to Term

• Current Assignee: Crossroads Systems (Texas) Incorporated (Crossroads Systems, Inc.)
• Original Assignee: Crossroads Systems (Texas) Incorporated (Crossroads Systems, Inc.)
• Inventors: Hoese, Geoffrey B., Russell, Jeffry T.
• Primary Examiner(s): Shin, Christopher B.
• Application Number:
  US10/174,720
• Publication Number:
  US 20020161950A1
• Time in Patent Office: 699 Days
• Field of Search: 710/1-5, 710/8-13, 710/22-28, 710/104-105, 710/305-316, 709/250
• US Class Current: 710/315
• 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. A device comprising:

a first buffer providing memory work space;

a first controller operable to connect to and interface with a first transport medium, wherein the first transport medium is operable according to a first protocol;

a second controller operable to connect to and interface with a second transport medium, wherein the second transport medium is operable according to a second protocol; and

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

to map between devices connected to the first transport medium and storage devices connected to the second transport medium,

to implement access controls for storage space on the storage devices and

to process data in the first buffer to interface between the first controller and the second controller to allow access from devices connected to the first transport medium to the storage devices using native low level, block protocols.

2. The device of claim 1, wherein the supervisor unit maintains an allocation of subsets of storage space to associated devices connected to the first transport medium, wherein each subset is only accessible by the associated device connected to the first transport medium.

3. The device of claim 2, wherein the devices connected to the first transport medium comprise workstations.

4. The device of claim 2, wherein the storage devices comprise hard disk drives.

5. The device of claim 1, wherein the first controller comprises:

a first protocol unit operable to connect to the first transport medium;

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

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

6. The device of claim 1, wherein the second controller comprises:

a second protocol unit operable to connect to the second transport medium;

an internal buffer coupled to the second protocol unit; and

a direct memory access (DMA) interface coupled to the internal buffer and to the first buffer.

7. The device of claim 1:

wherein the first protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA; and

wherein the second protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA.

8. The device of claim 1, wherein the first transport medium is separate from the second transport medium.

9. The device of claim 1, wherein the first protocol is different from the second protocol.

10. A storage network, comprising:

a first transport medium operable according to a first protocol;

a second transport medium operable according to a second protocol;

a plurality of workstations connected to the first transport medium;

a plurality of storage devices connected to the second transport medium; and

a storage router interfacing between the first transport medium and the second transport medium, the storage router providing virtual local storage on the storage devices to the workstations and operable;

to map between the workstations and the storage devices;

to implement access controls for storage space on the storage devices; and

to allow access from the workstations to the storage devices using native low level, block protocol in accordance with the mapping and access controls.

11. The storage network of claim 10, wherein the access controls include an allocation of subsets of storage space to associated workstations, wherein each subset is only accessible by the associated workstation.

12. The storage network of claim 10, wherein the storage devices comprise hard disk drives.

13. The storage network of claim 10, wherein the storage router comprises:

a buffer providing memory work space for the storage router;

a first controller operabie to connect to and interface with the first transport medium, the first controller further operable to pull outgoing data from the buffer and to place incoming data into the buffer;

a second controller operable to connect to and interface with the second transport medium, the second controller further operable to pull outgoing data from the buffer and to place incoming data into the buffer; and

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

to map between devices connected to the first transport medium and the storage devices, to implement the access controls for storage space on the storage devices and to process data in the buffer to interface between the first controller and the second controller to allow access from workstations to storage devices.

14. The storage network of claim 10:

wherein the protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA; and

wherein the second protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA.

15. The storage network of claim 10, wherein the first transport medium is separate from the second transport medium.

16. The storage network of claim 10, wherein the first protocol is different from the second protocol.

17. A method comprising:

interfacing with a first transport medium which is operable according to a first protocol;

interfacing with a second transport medium which is operable according to a second protocol;

mapping between devices connected to the first transport medium and storage devices connected to the second transport medium;

implementing access controls for storage space on the storage devices; and

allowing access from devices connected to the first transport medium to the storage devices using native low level, block protocols.

18. The method of claim 17, wherein mapping between devices connected to the first transport medium and the storage devices includes allocating subsets of storage space to associated devices connected to the first transport medium, wherein each subset is only accessible by the associated device connected to the first transport medium.

19. The method of claim 18, wherein the devices connected to the first transport medium comprise workstations.

20. The method of claim 18, wherein the storage devices comprise hard disk drives.

21. The method of claim 17:

wherein the first protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA; and

wherein the second protocol is selected from the group consisting of Fibre Channel, SCSI, iSCSI, Serial Attached SCSI, and Serial ATA.

22. The method of claim 17, wherein the first transport medium is separate from the second transport medium.

23. The method of claim 17, wherein the first protocol is different from the second protocol.