MULTIPATH REDUNDANT STORAGE SYSTEM ARCHITECTURE AND METHOD

• US 20080276033A1
• Filed: 07/14/2008
• Published: 11/06/2008
• Est. Priority Date: 04/02/2004
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Sicola, Stephen J., DeCenzo, David Peter, Pagano, William A.
• Granted Patent: US 8,024,602 B2
• Time in Patent Office: Days
• US Class Current: 710/316
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/2005 using redundant communication controllers
• CPC Class Codes: G06F 11/2007 using redundant communication media
• CPC Class Codes: G06F 11/201 between storage system components
• CPC Class Codes: G06F 11/2089 Redundant storage control functionality
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence

Abstract

Disclosed is a storage system and method that provides multi-path bus and component interconnection and isolation in a data storage system. A plurality of data storage devices in a removable assembly are connected to a fabric that is configurable to connect some or all of the data storage devices (or “drives”) to a drive controller and configurable to isolate one or more data storage devices from the drive controller. Multiple controllers, fabrics, and interconnecting buses may be employed to provide redundancy in the event of a connector, bus, or controller failure. Computer program code operating in a host, interface controller, and/or drive controller configures the fabric to isolate failed devices and may be employed to optimize data transfer rates. Data storage devices may be multi-ported. The fabric may comprise any device or devices capable of configurably interconnecting data storage devices to one or more controllers and may comprise multiplexers, cross point switches, port bypass controllers. Fabrics may also provide translation or conversion of one bus or interface format to another format.

Claims

1. An apparatus comprising a plurality of data storage devices and redundant storage controllers within a common enclosure, the storage controllers each selectively connectable to each of the plurality of data storage devices via a switchable fabric for controlling data transfer operations in relation to each of the data storage devices.

2. The apparatus of claim 1 comprising an interface controller within the enclosure configured for interfacing with an external device.

3. The apparatus of claim 1 wherein the switchable fabric is configured for switching by the storage controllers.

4. The apparatus of claim 2 wherein the switchable fabric is configured for switching by the interface controllers.

5. The apparatus of claim 2 wherein the switchable fabric is configured for switching by the external device.

6. The apparatus of claim 1 wherein the storage controllers are each connectable to each of the plurality of data storage devices via redundant switchable fabrics for controlling data transfer operations in relation to each of the data storage devices.

7. The apparatus of claim 6 wherein each of the data storage devices is dual ported, with a port of each data storage device connected to each of the switchable fabrics.

8. A multiple drive assembly comprising a plurality of data storage devices and a storage controller that is selectively connectable to each of the plurality of data storage devices via a switchable fabric defining at least two independent signal paths between the storage controller and each data storage device for controlling data transfers in relation to each of the data storage devices.

9. The multiple drive assembly of claim 8 comprising an interface controller configured for interfacing with an external device.

10. The multiple drive assembly of claim 8 wherein the switchable fabric is configured for switching by the storage controller.

11. The multiple drive assembly of claim 9 wherein the switchable fabric is configured for switching by the interface controllers.

12. The multiple drive assembly of claim 9 wherein the switchable fabric is configured for switching by the external device.

13. The multiple drive assembly of claim 8 comprising redundant storage controllers, each selectively connectable to each of the plurality of data storage devices via at least two independent signal paths defined by the switchable fabric.

14. The multiple drive assembly of claim 13 comprising redundant switchable fabrics connected to the redundant controllers for communicating data transfer information in relation to each of the data storage devices.

15. The multiple drive assembly of claim 14 wherein each of the data storage devices is dual ported, with a port of each data storage device connected to each of the switchable fabrics.

16. A method comprising:

forming a multiple drive assembly by connecting each of a plurality of data storage devices to a switchable fabric;

determining whether all the data storage devices are accessible via the fabric; and

configuring the fabric to isolate any inaccessible data storage devices.

17. The method of claim 16 wherein the forming step comprises connecting each of the plurality of data storage devices to each of redundant switchable fabrics.

18. The method of claim 17 wherein the determining step comprises determining whether all the data storage devices are accessible via a first of the fabrics, and determining whether all the data storage devices are accessible via a second of the fabrics.

19. The method of claim 18 wherein the forming step comprises connecting redundant storage controllers to the first and second fabrics via first and second fabric busses, respectively, determining whether the first fabric is accessible via each of the first and second fabric busses, and determining whether the second fabric is accessible via each of the first and second fabric busses.

20. The method of claim 19 wherein the forming step comprises connecting redundant interface controllers to the storage controllers via first and second interface busses, respectively, determining whether a first of the storage controllers is accessible via each of the first and second interface busses, and determining whether a second of the storage controllers is accessible via each of the first and second interface busses.