System and method for resolving fibre channel device addresses on a network using the device's fully qualified domain name

• US 6,199,112 B1
• Filed: 09/23/1998
• Issued: 03/06/2001
• Est. Priority Date: 09/23/1998
• Status: Expired due to Term

• Current Assignee: CF DB EZ LLC (FIG LLC (d/b/a Fortress Investment Group LLC))
• Original Assignee: Crossroads Systems (Texas) Incorporated (Crossroads Systems, Inc.)
• Inventors: Wilson, Stephen K.
• Primary Examiner(s): Rinehart, Mark H.
• Assistant Examiner(s): KANG, PAUL H
• Application Number:
  US09/158,991
• Time in Patent Office: 895 Days
• Field of Search: 709/222, 709/226, 709/227, 709/245, 710/129, 710/9, 359/118, 340/825, 340/825.52, 340/825.53, 370/475
• US Class Current: 709/227
• CPC Class Codes: H04L 2101/645 Fibre channel identifiers
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]

Abstract

A method and system for discovering the location of a storage router, and therefore the attached storage devices, in a fibre channel network using the storage router'"'"'s fully qualified domain name to ultimately determine the storage router'"'"'s arbitrated loop physical address (AL_PA). An Internet protocol domain name query containing the fully qualified domain name is sent from a host computer over the storage area network to a domain name server to determine an Internet Protocol address for the storage router. The domain name server replies with the storage router Internet Protocol address. The host computer then sends an address resolution protocol request containing the Internet protocol address over the storage area network to determine a node name for the storage router. The storage router replies with its node name. The host computer then sends an FCP request containing the storage router'"'"'s node name over the storage area network to determine an arbitrated loop physical address of the storage router. The storage router replies with its arbitrated loop physical address. The host computer can use a variety of standard inquiries discover storage devices attached to the storage router. The communication can then continue in fibre channel protocol between the storage and the host computer.

Claims

1. A method for resolving a fibre channel device address on a network from a fully qualified domain name of a device, comprising:

sending a domain name query containing the fully qualified domain name from a host computer over the network to a domain name server to determine an Internet Protocol address for the device;

locating at the domain name server the Internet Protocol address for the device based on the fully qualified domain name;

sending the device Internet Protocol address to the host computer;

sending an address resolution protocol request containing the Internet protocol address from the host computer over the storage area network to determine a node name for the device;

sending an address resolution protocol reply containing the device node name to the host computer;

sending a fibre channel address resolution protocol request containing the device node name from the host computer to the device to determine a physical address of the device; and

sending a fibre channel address resolution protocol reply containing the device physical address to the host computer.

2. The method of claim 1, wherein the device is a storage router capable of supporting both fibre channel protocol and address resolution protocol, and further wherein the network is a storage area network.

3. The method of claim 2, wherein the storage router has a fibre channel interface that is addressable by the Internet Protocol address.

4. The method of claim 2, further comprising sending a storage device inquiry from the host computer to the storage router to discover a storage device attached to the storage router.

5. The method of claim 4, further comprising:

determining from a reply to the storage device inquiry if the storage device is compatible with a client application resident on the host computer; and

if the storage device and client application are compatible, exchanging data between the storage device and the host computer.

6. The method of claim 5, wherein the data exchanging between the storage device and the host computer is accomplished using fibre channel protocol.

7. The method of claim 4, wherein the storage device inquiry discovers a plurality of storage devices.

8. The method of claim 4, wherein the device physical address is the arbitrated loop physical address for the storage device.

9. The method of claim 4, wherein each step of sending a request from the host computer is facilitated by the client application resident on the host computer.

10. The method of claim 4, wherein the storage device is directly attached to the storage router.

11. The method of claim 4, wherein the storage device is attached via an arbitrated loop to the storage router.

12. The method of claim 4, wherein discovering the storage device further comprises using a REPORT LUNS command as defined by the SCSI specification.

13. The method of claim 1, wherein the network is a storage area network.

14. The method of claim 1, wherein the domain name query and domain name reply are Internet protocol.

15. A method for resolving a fibre channel device address on a storage area network from a fully qualified domain name of a storage router capable of supporting both fibre channel protocol and address resolution protocol, comprising:

sending an Internet protocol domain name query containing the fully qualified domain name from a host computer over the storage area network to a domain name server to determine an Internet Protocol address for the storage router;

locating at the domain name server the Internet Protocol address for the storage router based on the fully qualified domain name;

sending an Internet protocol reply containing storage router Internet Protocol address from the domain name server to the host computer;

sending an address resolution protocol request containing the Internet protocol address from the host computer over the storage area network to determine a node name for the storage router;

sending an address resolution protocol reply containing the storage router node name to the host computer;

sending a fibre channel address resolution protocol request containing the device node name from the host computer to the storage router to determine an arbitrated loop physical address of the storage router; and

sending a fibre channel address resolution protocol reply containing the storage router arbitrated loop physical address to the host computer.

16. The method of claim 15, further comprising:

sending a storage device inquiry from the host computer to the storage router to discover a storage device attached to the storage router;

determining from a reply to the storage device inquiry if the storage device is compatible with the host computer; and

if the storage device and application are compatible, exchanging data between the storage device and the host computer using fibre channel protocol.

17. A system for resolving a fibre channel device address from a fully qualified domain name of a device in a storage area network, comprising:

a storage router, comprising a fibre channel interface that supports both fibre channel protocol and address resolution protocol;

a host computer capable of supporting Internet protocol and fibre channel protocol, the host computer comprising;

a client application; and

a data file containing a list of fully qualified domain names for each storage router in the storage area network; and

a domain name server comprising a resource record look-up table, wherein the resource record look-up table contains the Internet protocol address and fully qualified domain name of the storage router configured such that the Internet protocol address can be discovered from the fully qualified domain name, and wherein;

the client application is operable to access the data file and send a domain name query containing the fully qualified domain name for the storage router over the storage area network to the domain name server to determine the Internet Protocol address for the storage router;

the domain name server discovers the Internet Protocol address for the storage router based on the fully qualified domain name and sends the storage router Internet Protocol address to the client application;

the client application sends an address resolution protocol request containing the Internet protocol address over the storage area network to determine a node name for the storage router;

the storage router sends an address resolution protocol reply containing the storage router node name to the client application;

the client application sends a fibre channel address resolution protocol request containing the storage router node name to the storage router to determine a physical address of the storage router; and

the storage router sends a fibre channel address resolution protocol reply containing the device physical address to the client application.

18. The system of claim 17, further comprising at least one storage device attached to the storage router, and wherein the client application further sends a storage device inquiry to the storage router to discover a storage device attached to the storage router.

19. The system of claim 18, wherein the client application further determines from a reply to the storage device inquiry whether the storage device is compatible with the client application, and if the storage device and client application are compatible, exchanging data between the storage device and the host computer using fibre channel protocol.

20. The system of claim 19, wherein the storage device inquiry discovers a plurality of storage devices.

21. The system of claim 19, wherein discovering the storage device further comprises using a REPORT LUNS command as defined by the SCSI specification.

22. A system for resolving a storage router physical address from a fully qualified domain name of a storage router in a storage area network, comprising:

a host computer capable of supporting Internet protocol and fibre channel protocol, comprising;

a host processor;

a host memory;

a dns query software program resident on the host memory;

an ARP request software program residing on the host memory; and

a FARP request software program residing on the host memory;

a domain name server capable of supporting Internet protocol and fibre channel protocol, comprising;

a domain name server processor;

a domain name server memory;

a resource record look-up table containing the Internet protocol address and fully qualified domain name of the storage router, such resource record look-up table configured in a way that the Internet protocol address can be discovered from the fully qualified domain name; and

a dns reply software program resident on the domain name server memory; and

a storage router, comprising;

a fibre channel interface that is addressable by the Internet Protocol address to allow support of both fibre channel protocol and address resolution protocol;

a storage router processor;

a storage router memory

an ARP reply software program resident on the storage router memory; and

a FARP reply software program resident on the storage router memory, and wherein;

the dns query software program is operable to direct the host processor to send a domain name query containing the fully qualified domain name of the storage router over the storage area network to the domain name server;

the dns reply software program is operable to direct the domain name server to access the resource record look-up table and discover the Internet Protocol address for the storage router based on the fully qualified domain name in the domain name query and to send a dns reply to the host computer that contains the storage router Internet Protocol address;

the ARP request software program operable to direct the host processor to send an address resolution protocol request containing the storage router Internet protocol address over the storage area network to determine a node name for the storage router;

the ARP reply software program operable to direct the storage router processor to send an address resolution protocol reply containing the storage router node name to the host computer;

the FARP request software program operable to direct the host processor to send a fibre channel address resolution protocol request containing the storage router node name to the storage router to determine a physical address of the storage router; and

the FARP reply software program operable to direct the storage router processor to send a fibre channel address resolution protocol reply containing the storage router physical address to the client application.

23. The system of claim 22, further comprising:

a data file containing a list of fully qualified domain names for each storage router in the storage area network; and

a client application resident on the host memory, the client application operable to direct the host processor to access the data file, obtain the fully qualified domain name of the storage router, and send the domain name query to the domain name server.

24. The system of claim 23, further comprising at least one storage device attached to the storage router, and wherein the client application further sends a storage device inquiry to the storage router to discover the storage device attached to the storage router.

25. The system of claim 24, wherein the client application further determines from a reply to the storage device inquiry whether the storage device is compatible with the client application, and if the storage device and client application are compatible, exchanging data between the storage device and the host computer using fibre channel protocol.