Trunking for fabric ports in fibre channel switches and attached devices

• US 20060092932A1
• Filed: 11/01/2004
• Published: 05/04/2006
• Est. Priority Date: 11/01/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Desai, Tushar, Gupta, Shashank, Jain, Praveen, Ghosh, Kalyan K.
• Granted Patent: US 7,916,628 B2
• Time in Patent Office: Days
• US Class Current: 370/389
• CPC Class Codes: H04L 49/25 Routing or path finding in a switch fabric
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/357 Fibre channel switches

Abstract

N_Ports and F_Ports are provided with logic allowing designation of multiple virtual interfaces on a single host bus adaptor or other Fibre Channel interface, one virtual interface for each VSAN operating on the node interface. Node ports with this additional functionality are referred to as trunking N_Ports or TN_Ports. These ports have a functional design allowing creation of the multiple virtual interfaces as appropriate for the application at hand. This port design also includes logic for communicating with a peer fabric port to initialize and modify the configuration of the virtual interfaces on the TN_Port. A corresponding functional design and communication logic is provided for fabric ports, referred to herein as trunking F_Ports or TF_Ports.

Claims

1. A trunking N_Port for a Fibre Channel node, the trunking N_Port comprising:

a physical N_Port interface designed or configured to provide functionality of a non-trunking N_Port when virtual SAN functionality is not available; and

a controller for managing trunking on the trunking N_Port, wherein the controller is designed or configured to communicate with an F_Port on a Fibre Channel switch and determine whether virtual SAN functionality is available and if so define one or more virtual SAN interfaces on the trunking N_Port, with each virtual SAN interface providing the functionality of an N_Port for a single virtual SAN.

2. The trunking N_Port of claim 1, wherein the trunking N_Port is implemented at least partially as software.

3. The trunking N_Port of claim 1, further comprising one or more instances of said virtual SAN interfaces.

4. The trunking N_Port of claim 1, wherein the physical N_Port functionality provides no information regarding virtual SANs in frames transmitted therefrom.

5. The trunking N_Port of claim 1, wherein one or more of the virtual SAN interfaces is designed or configured to provide frames containing information identifying the particular virtual SAN to which it belongs.

6. The trunking N_Port of claim 5, wherein the information identifying the particular virtual SAN to which it belongs is provided in an EISL header for the frames.

7. The trunking N_Port of claim 5, wherein the frames comprise QoS parameters defining levels of quality of service available for the virtual SANs.

8. The trunking N_Port of claim 1, wherein the controller is designed or configured to communicate with the F_Port using EPP protocol.

9. The trunking N_Port of claim 1, wherein the controller has a Fibre Channel well known address but is designed or configured such that it does not take part in data traffic.

10. The trunking N_Port of claim 1, wherein the controller is designed or configured to negotiate a mode of operation with the F_Port and available modes of operation include trunking and non-trunking.

11. The trunking N_Port of claim 1, wherein the controller is designed or configured to identify VSANs common to the F_Port and the trunking N_Port, to thereby define one or more virtual SAN interfaces on the trunking N_Port.

12. The trunking N_Port of claim 11, wherein the controller is designed or configured to use EPP protocol to identify VSANs common to the F_Port and the trunking N_Port.

13. A trunking N_Port or F_Port for a Fibre Channel device, the trunking N_Port or F_Port comprising a controller for managing trunking on the trunking N_Port or F_Port, wherein the controller is designed or configured to communicate with a peer port over a Fibre Channel link and determine whether virtual SAN functionality is available and if so define one or more virtual SAN interfaces on the trunking N_Port or F_Port, with each virtual SAN interface providing the functionality of a single virtual SAN.

14. The trunking N_Port or F_Port of claim 13, wherein the controller is designed or configured to negotiate a mode of operation with the peer and available modes of operation include trunking and non-trunking.

15. The trunking N_Port or F_Port of claim 13, wherein the controller is designed or configured to identify VSANs common to the F_Port and the trunking N_Port, to thereby define one or more virtual SAN interfaces on the trunking N_Port.

16. The trunking N_Port or F_Port of claim 15, wherein the controller is designed or configured to use EPP protocol to identify VSANs common to the F_Port and the trunking N_Port.

17. A storage area network comprising:

(a) two or more nodes, each comprising a trunking N_Port coupled to a Fibre Channel link; and

(b) one or more Fibre Channel switches comprising multiple F_Ports in communication with the trunking N_Ports and defining a fabric allowing communication among the two or more nodes,

wherein the trunking N_Ports comprise controllers designed or configured to communicate with F_Ports on a Fibre Channel switch and determine whether virtual SAN functionality is available and if so define one or more virtual SAN interfaces on their trunking N_Ports, with each virtual SAN interface providing the functionality of an N_Port for a single virtual SAN.

18. The storage area network of claim 17, wherein the two or more nodes comprise one or more storage nodes and one or more host nodes.

19. The storage area network of claim 17, wherein the controllers communicate with the F_Ports using EPP protocol.

20. The storage area network of claim 17, wherein the controllers employ the EPP protocol to identify VSANs common to the F_Ports and the trunking N_Ports.

21. A method of establishing a link between a trunking N_Port on a node and an F_Port on a Fibre Channel switch, the method comprising:

(a) determining whether virtual SAN functionality exists on the F_Port; and

(b) defining one or more virtual SAN interfaces on the trunking N_Port, with each virtual SAN interface providing the functionality of an N_Port for a single virtual SAN.

22. The method of claim 21, wherein (a) and (b) are both implemented by communicating between the trunking N_Port on a node and the F_Port.

23. The method of claim 22, wherein the communicating comprises exchanging frames in EPP protocol.

24. The method of claim 21, further comprising transmitting frames from the one or more of the virtual SAN interfaces, which frames containing information identifying the particular virtual SAN to which it belongs.

25. The method of claim 24, wherein the information identifying the particular virtual SAN to which it belongs is provided in an EISL header for the frames.

26. The method of claim 24, wherein the frames comprise QoS parameters defining levels of quality of service available for the virtual SANs.

27. The method of claim 21, further comprising conducting a negotiation between the trunking N_Port and the F_Port to determine a mode of operation with the F_Port, wherein available modes of operation include trunking and non-trunking.

28. A computer program product comprising a machine readable medium on which is provided program instructions for establishing a link between a trunking N_Port on a node and an F_Port on a Fibre Channel switch, wherein the program instructions comprise:

(a) code for determining whether virtual SAN functionality exists on the F_Port; and

(b) code for defining one or more virtual SAN interfaces on the trunking N_Port, with each virtual SAN interface providing the functionality of an N_Port for a single virtual SAN.

29. The computer program product of claim 28, wherein the program code for both (a) and (b) comprises code for communicating between the trunking N_Port on a node and the F_Port.

30. The computer program product of claim 29, wherein the code for communicating comprises code for exchanging frames in EPP protocol.

31. The computer program product of claim 28, further comprising code for transmitting frames from the one or more of the virtual SAN interfaces, which frames containing information identifying the particular virtual SAN to which it belongs.

32. The computer program product of claim 31, wherein the code for transmitting frames comprises code for providing an EISL header for the frames.

33. The computer program product of claim 31, wherein the code for transmitting frames comprises code for providing QoS parameters defining levels of quality of service available for the virtual SANs.

34. The computer program product of claim 28, further comprising code for conducting a negotiation between the trunking N_Port and the F_Port to determine a mode of operation with the F_Port, wherein available modes of operation include trunking and non-trunking.

35. A trunking N_Port for a Fibre Channel node, the trunking N_Port comprising:

(a) means for determining whether virtual SAN functionality exists on a F_Port to which the trunking N_Port is linked; and

(b) means for defining one or more virtual SAN interfaces on the trunking N_Port, with each virtual SAN interface providing the functionality of an N_Port for a single virtual SAN.

36. The trunking N_Port of claim 35, wherein the means for determining is designed or configured to exchange frames in EPP protocol.

37. The trunking N_Port of claim 35, further comprising means for transmitting frames from the one or more of the virtual SAN interfaces, which frames containing information identifying the particular virtual SAN to which it belongs.

38. The trunking N_Port of claim 37, wherein the information identifying the particular virtual SAN to which it belongs is provided in an EISL header for the frames.

39. The trunking N_Port of claim 37, wherein the frames comprise QoS parameters defining levels of quality of service available for the virtual SANs.

40. The trunking N_Port of claim 35, further comprising means for conducting a negotiation between the trunking N_Port and the F_Port to determine a mode of operation with the F_Port, wherein available modes of operation include trunking and non-trunking.