Redirecting local disk traffic to network attached storage

• US 20030154314A1
• Filed: 02/07/2003
• Published: 08/14/2003
• Est. Priority Date: 02/08/2002
• Status: Abandoned Application

• Current Assignee: I/O Integrity Incorporated
• Original Assignee: I/O Integrity Incorporated
• Inventors: Mason, Robert S. Jr., Garrett, Brian L.
• Application Number:
  US10/361,483
• Publication Number:
  US 20030154314A1
• Time in Patent Office: Days
• US Class Current: 709/250
• CPC Class Codes: H04L 2101/622 Layer-2 addresses, e.g. medium access control [MAC] addresses
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming

Abstract

An apparatus and method implemented in embedded software that transparently redirects local hard drive requests to a Network Attached Storage (NAS) subsystem is provided. The apparatus, contains a large front end cache used to intercept local hard disk I/O requests at the lowest level before forwarding to an external network attached NAS subsystem, providing a transparent high performance centrally managed storage solution.

Claims

1. A data processing system comprising:

a host Central Processing Unit CPU, located within a housing, the host CPU running a host operating system, and the host CPU having a system bus for interconnecting other data processing system components to the host CPU;

an I/O interface for connecting the host system bus to an I/O device bus so that data may be transferred to and from the host CPU;

a network interface, for accessing data to be read and written by the host CPU via a network attached storage unit; and

a storage manager, the storage manager being located within the same housing as the host processor, the storage manager connected to receive data from both the processor and the network interface, the storage manager providing a programming environment that is independent of the host operating system, and the storage manager intercepting requests for access to a local disk drive that occur on the I/O interface, and redirecting such requests to the network interface in a manner that is independent of the host system bus configuration.

2. A system as in claim 1 wherein the storage manager is located in an in-band location on the I/O device bus between the I/O interface and the disk storage unit.

3. A system as in claim 1 wherein the storage manager additionally comprises a user interface to provide a user access to configuration data.

4. A system as in claim 1 wherein storage manager commands are sent to the apparatus inter-mingled within an I/O stream over the device I/O bus.

5. A system as in claim 1 wherein storage manager commands are sent to the apparatus through the Ethernet interface by means of a telnet or Hyper Text Transfer Protocol (HTTP) a TCP/IP interface.

6. A system as in claim 1 wherein the disk storage interface is configured as a standard disk storage interface selected from the group consisting of Integrated Device Electronics (IDE), Enhanced IDE (EIDE), Advanced Technology Attachment (ATA), serial Advanced Technology Attachment (ATA), Small Computer System Interface (SCSI), Internet SCSI (iSCSI), Advanced Technology Attachment (ATA), and Fiber Channel.

7. A system as in claim 1 wherein a front end bus interface of the storage manager connected to the host I/O interface may have a different standard interface specification than that of a back end bus interface of the storage manager connected to the hard disk drive(s).

8. A system as in claim 7 wherein the front end and back end I/O bus interfaces are Small Computer System Interface (SCSI) compatible.

9. A system as in claim 6 wherein a front end and a back end I/O bus interface are Integrated Device Electronics (IDE) compatible.

10. A system as in claim 7 wherein the front bus I/O interface is Small Computer System Interface(SCSI) compatible and the back end I/O interface is Integrated Device Electronics (IDE) compatible.

11. A system as in claim 1 wherein the storage manager uses a software architecture implemented over a multithreaded real time operating system to isolate a front end interface, network interface, and management functions as separate tasks.

12. A system as in claim 1 wherein the storage manager is provided within a standard disk drive enclosure format.

13. A system as in claim 1 wherein the storage manager is provided in a Peripheral Component Interconnect (PCI) interface board format.

14. A system as in claim 1 wherein the storage manager is provided in an integrated circuit format.

15. A system as in claim 1 wherein the storage manager intercepts drive requests based on logical block addresses and translates them to byte offsets within a file residing on the network attached storage.

16. A system as in claim 1 wherein the storage manager maps disk access requests for specific local drive blocks to Network File System file names.

17. A system as in claim 14 wherein the Network File System file names contain an address of the network interface.

18. A system as in claim 15 wherein the address of the network interface is a Media Access Control (MAC) layer address.

19. A system as in claim 1 wherein the storage manager intercepts drive requests arriving on the front end I/O bus interface which are based on logical block addresses and forwards them over the network interface as block requests directed towards an Internet Small Computer System Interface (iSCSI) storage subsystem.