Apparatus for bridging a host to a SAN

Abstract
The present invention discloses a bridging apparatus for bridging a host to a SAN (Storage Area Network). The bridging apparatus is capable of virtualizing a disk volume allocated in the SAN as a DAS (Direct Attached Storage). The bridging apparatus of the present invention comprises: a first HBA (Host Bus Adapter) for connecting to a SAN, a second HBA for connecting to a host having a DAS interface, a bridge controller for connecting to the first HBA and the second HBA, respectively, so as to bridge the host to the SAN, thereby allowing the host to directly access a disk volume allocated in the SAN, and a storage unit connecting to the bridge controller for storing programs and data.
Description

BRIEF DESCRIPTION OF THE DRAWINGS


FIG. 1 illustrates an architecture of SAN;



FIG. 2 illustrates a first preferred embodiment of the bridging apparatus of the present invention;



FIG. 3 illustrates a second preferred embodiment of the bridging apparatus of the present invention; and



FIG. 4 illustrates a third preferred embodiment of the bridging apparatus of the present invention.





DETAILED DESCRIPTION

A preferred embodiment of the present invention is described in detail below. However, the present invention can be widely applied in embodiments other than those described in the detailed description, and the scope of the present invention is not limited by the embodiment, but is defined by the appended claims.


The present invention discloses a bridging apparatus for bridging a host to a SAN, and the bridging apparatus is capable of virtualizing a disk volume allocated in the SAN as a DAS drive. Through a DAS interface, e.g. SCSI, USB, SAS or SATA with support of port multiplier, the host can attach multiple virtual DAS drives simultaneously. The bridging apparatus comprises: a first HBA for connecting to a SAN, a second HBA for connecting to a host having a DAS interface, a bridge controller for connecting to the first HBA and the second HBA, respectively, so as to bridge the host to the SAN, thereby allowing the host to directly access a disk volume allocated in the SAN, and a storage unit connecting to the bridge controller for storing program and data.



FIG. 2 illustrates a first preferred embodiment of the bridging apparatus of the present invention. The bridging apparatus 100 is used to bridge a virtual DAS to a SAN wherein the bridging apparatus 100 comprises an iSCSI HBA 150 for connecting to an IP SAN, a DAS HBA 110 for connecting to a host having a DAS interface, and a bridge controller 130 for connecting to the iSCSI HBA 150 and the DAS HBA 110, respectively. The host in the embodiment can be a workstation, a laptop computer, a server, a desktop computer or an industrial computer.


The foregoing DAS HBA 110 may connect to one of the SCSI, SATA (Serial ATA), eSATA (External SATA), USB or SAS (Serial Attached SCSI) interfaces. However, persons skilled in the art know that the accomplishment of the present invention should not be limited by the above interfaces.


Further, the bridging apparatus 100 includes a flash memory 140 and a DRAM 120 respectively connecting to the bridge controller 130. The DRAM 120 is used to be a cache memory of the disk volume for the SAN so as to speed up access to the SAN, and the flash memory 140 is used to store programs and data needed by the bridge controller 130.



FIG. 3 illustrates a second preferred embodiment of the present invention. The difference between in FIG. 2 and FIG. 3, the iSCSI HBA 150 connecting to the SAN is replaced by an Ethernet NIC 170 (Ethernet Network Interface Card). The Ethernet NIC 170 uses resources of the host to simulate iSCSI or AoE (ATA over Ethernet) protocol by software computing.



FIG. 4 illustrates a third preferred embodiment of the present invention. The difference between in FIG. 2 and FIG. 4, the iSCSI HBA 150 connecting to the SAN is replaced by an FC HBA 180 (Fiber Channel HBA). In other word, the bridging apparatus of the present invention may connect to a FC SAN via an FC interface.


The bridging apparatus of the present invention may simplify connecting from a DAS to a SAN and provides the following advantages: 1) Plug-and-play without additional driver. 2) Hosts connecting to the SAN may boot-up through a disk volume allocated in the SAN without additional boot ROM. Since a disk volume of the SAN is assigned to a host connecting to the SAN via the bridging apparatus of the present invention, the host may boot-up without any local disk. In fact, the host will deem the disk volume allocated in the SAN as a local disk. 3) Therefore, the host connecting to the SAN may directly access the volume disk allocated in the SAN as accessing a local disk. 4) The host connecting to the SAN via the bridging apparatus of the present invention does not need any local disk. Instead, a storage space in the SAN will be assigned to the host connecting to the SAN, such that IT persons may centralize managing and allocating disk spaces for hosts connecting to the SAN. 5) In addition, the bridging apparatus of the invention may be used in different platforms.


The above description is only a preferred embodiment of the present invention, and not used to limit the claims of the present invention. All equivalent variations or modifications performed without departing from the spirit disclosed in the present invention are within the following claims.

Claims
  • 1. A bridging apparatus for bridging a host to a SAN, comprising: a first HBA for connecting to the SAN;a second HBA for connecting to a host having a DAS interface;a bridge controller connecting to the first HBA and the second HBA, respectively, for bridging the host to the SAN, thereby allowing the host to directly access a disk volume allocated in the SAN; anda storage unit connecting to the bridge controller for storing programs and data.
  • 2. The bridging apparatus as claimed in claim 1, wherein the first HBA is an iSCSI interface.
  • 3. The bridging apparatus as claimed in claim 1, wherein the first HBA is a fiber channel interface.
  • 4. The bridging apparatus as claimed in claim 1, wherein the storage unit includes a flash memory and a DRAM in which the DRAM is used to be a cache memory and thereby speed up access to the disk volume of the SAN, and the flash memory is used to store programs and data needed by the bridge controller.
  • 5. The bridging apparatus as claimed in claim 1, wherein the host is a workstation.
  • 6. The bridging apparatus as claimed in claim 1, wherein the host is a laptop computer.
  • 7. The bridging apparatus as claimed in claim 1, wherein the host is a server.
  • 8. The bridging apparatus as claimed in claim 1, wherein the host is a personal computer.
  • 9. The bridging apparatus as claimed in claim 1, wherein the DAS interface is one of the interfaces of SCSI, SATA (Serial ATA), eSATA (External SATA), USB or SAS (Serial Attached SCSI).
  • 10. The bridging apparatus as claimed in claim 1, wherein the first HBA for the SAN and the second HBA for the DAS can be integrated with the bridge controller in a single chip in SoC (System on Chip) implementation.
  • 11. A bridging apparatus for bridging a host to a SAN, comprising: an HBA for connecting to a host having a DAS interface;an Ethernet interface card for connecting to the SAN and the Ethernet interface card performing iSCSI or AoE (ATA over Ethernet) protocol by software simulation;a bridge controller connecting to the HBA and the Ethernet interface card, respectively, for bridging the host to the SAN, thereby allowing the host to directly access a disk volume allocated in the SAN;a DRAM connecting to the bridge controller for speeding up access to the disk volume of the SAN; anda flash memory connecting to the bridge controller for storing programs and data needed by the bridge controller.
  • 12. The bridging apparatus as claimed in claim 11, wherein the HBA is an iSCSI interface.
  • 13. The bridging apparatus as claimed in claim 11, wherein the HBA is a fiber channel interface.
  • 14. The bridging apparatus as claimed in claim 11, wherein the host is a workstation.
  • 15. The bridging apparatus as claimed in claim 11, wherein the host is a laptop computer.
  • 16. The bridging apparatus as claimed in claim 11, wherein the host is a server.
  • 17. The bridging apparatus as claimed in claim 11, wherein the host is a desktop personal computer.
  • 18. The bridging apparatus as claimed in claim 11, wherein the host is an industrial computer.
  • 19. The bridging apparatus as claimed in claim 11, wherein the DAS interface is one of the interfaces of SCSI, SATA (Serial ATA), eSATA (External SATA), USB or SAS (Serial Attached SCSI).