Storage router and method for providing virtual local storage

• US 7,689,754 B2
• Filed: 09/07/2007
• Issued: 03/30/2010
• Est. Priority Date: 12/31/1997
• Status: Expired due to Fees

• 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:
  US11/851,724
• Publication Number:
  US 20080046601A1
• Time in Patent Office: 935 Days
• Field of Search: 710 1- 5, 710 8- 13, 710 36- 38, 710126-131, 710/250, 709/258, 714/42, 711110-113
• US Class Current: 710/305
• 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 storage router for providing virtual local storage on remote storage devices to host devices, comprising:

a buffer providing memory work space for the storage router;

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

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

a supervisor unit coupled to the first controller, the second controller and the buffer, the supervisor unit operable to map between host devices connected to the serial transport medium and the 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 buffer to interface between the first controller and the second controller to allow access between host devices connected to the serial transport medium and the storage devices through using low level, block protocols.

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

3. The storage router of claim 2, wherein the storage router is further operable to receive a communication from the host device at the first controller, access the map to determine if the host device is allowed access to the subset of storage space for which the communication is intended, and send a low level block protocol command communication to the intended subset of the storage space if the host device is determined to be allowed access.

4. The storage router of claim 1, wherein the serial transport medium is an Ethernet transport medium, wherein the host device is operable to communicate using the iSCSI protocol, and wherein the first controller receives an iSCSI communication from the host device, the iSCSI communication comprising a SCSI command, and the supervisor unit forwards the SCSI command to one or more storage devices or portions thereof for which the host device is allowed access.

5. The storage router of claim 3, wherein the storage devices comprise SCSI, Fibre Channel, ATA, SATA or Serial Attached SCSI storage devices.

6. The storage router of claim 5, wherein the supervisor unit forwards a low level block protocol command to the storage devices.

7. A method for providing virtual local storage on remote storage devices to host devices connected to a serial transport medium, comprising:

interfacing with the serial transport medium;

interfacing with a second transport medium;

mapping between host devices connected to the serial transport medium and the storage devices;

implementing access controls for storage space on the storage devices in accordance with the mapping; and

allowing access from host devices connected to the serial transport medium to the storage devices connected to the second transport medium through using low level, block protocols.

8. The method of claim 7, wherein mapping between host devices connected to the serial transport medium and the storage devices includes allocating subsets of storage space to associated host devices, wherein each subset of storage space is only accessible by the associated host device.

9. The method claim 8, further comprising:

receiving a serial protocol communication from the host device at the first controller;

accessing the map to determine if the host device is allowed access to the subset of storage space for which the serial protocol communication is intended; and

sending a low level block protocol communication to the intended subset of the storage space if the host device is determined to be allowed access to the intended subset of storage space.

10. The method of claim 9, wherein the serial transport medium is an Ethernet transport medium, wherein the host device is operable to communicate using the SCSI protocol, and wherein the first controller receives an iSCSI communication from the host device, the iSCSI communication comprising a SCSI command, and the supervisor unit forwards the SCSI command to one or more storage devices or portions thereof for which the host device is allowed access;

wherein the storage devices comprise SCSI, Fibre Channel, ATA, SATA or Serial Attached SCSI storage devices.

11. A storage network, comprising:

a serial transport medium;

a second transport medium;

a plurality of workstations connected to the serial transport medium;

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

a routing device interfacing between the serial transport medium and the second transport medium, the routing device 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 low level, block protocol in accordance with the mapping and access controls.

12. The storage network of claim 11, 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.

13. The storage network of claim 11, wherein the map creates a path between unique identifiers associated with each of the workstations to unique identifiers associated with the storage devices.

14. The storage network of claim 11, wherein the routing device comprises:

a buffer providing memory work space for the routing device;

a first controller operable to communicate with the serial 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 communicate 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 in communication with the first and second controllers and the buffer, the supervisor unit operable;

to maintain a configuration for the storage devices that maps between the workstations and storage devices and that implements 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 in accordance with the configuration.

15. The storage network of claim 11, wherein the storage devices comprise SCSI storage devices.

16. The storage network of claim 11, wherein the storage devices comprise Fibre Channel storage devices.

17. The storage network of claim 11, wherein the storage devices comprise ATA storage devices.

18. The storage network of claim 11, wherein the storage devices comprise SATA storage devices.

19. The storage network of claim 11, wherein the storage devices comprise SAS storage devices.

20. The storage network of claim 11, wherein the serial transport medium is an Ethernet transport medium operable to transport iSCSI protocol communications.

21. The storage network of claim 11, wherein the serial transport medium is a Fibre Channel transport medium operable to transport Fibre Channel protocol communications.