Method and apparatus for detecting and removing orphaned primitives in a fibre channel network

• US 7,453,802 B2
• Filed: 07/12/2004
• Issued: 11/18/2008
• Est. Priority Date: 07/16/2003
• Status: Expired due to Fees

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: QLogic Corporation (Marvell Technology Group Limited)
• Inventors: Wen, William J., Fike, John M
• Primary Examiner(s): Pham; Chi H.
• Assistant Examiner(s): Hyun; Soon D.
• Application Number:
  US10/889,259
• Publication Number:
  US 20050013258A1
• Time in Patent Office: 1,590 Days
• Field of Search: 370/252
• US Class Current: 370/230
• CPC Class Codes: H04L 49/253 using establishment or release of connections between ports
• CPC Class Codes: H04L 49/357 Fibre channel switches
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance

Abstract

A method and system for detecting orphaned CLS primitives in a fibre channel network having a fibre channel switch element coupled to an arbitrated loop is provided. The method includes, sending an OPN primitive to a switch element port'"'"'s own AL_PA to open a connection with itself; and determining if a CLS primitive is received within a loop a latency period. If a CLS primitive is received within the latency period then the CLS primitive is classified as an orphan and the orphaned CLS primitive is removed by the switch element by enabling a firmware based removal feature. The switch element includes a port that arbitrates for the arbitrated loop ownership and sends an OPN primitive to its own AL_PA.

Claims

1. A method for detecting orphaned close (CLS) primitives in a fibre channel network having a fibre channel switch element coupled to an arbitrated loop, the method comprising:

sending an open (OPN) primitive from a switch element port to its own arbitrated loop physical address (AL_PA) to open a connection with itself; and

determining if a CLS primitive is received by the switch element port within a loop latency period; and

if a CLS primitive is received within the latency period, then the CLS primitive is classified as an orphan;

wherein

the latency period is either set at a desired value or determined.

2. The method of claim 1, further comprising the step of removing the orphaned CLS primitive by enabling a firmware based removal feature.

3. The method of claim 2, wherein by removing the CLS primitive traffic disruption is minimized.

14. The method of claim 2, wherein the step of removing the orphaned CLS primitive comprises replacing the orphaned CLS primitive with a Current Fill Word value.

15. The method of claim 1, wherein the latency period is determined by counting the time it takes for a primitive sent by the port to itself to traverse the loop.

4. A method for removing orphaned close( CLS) primitives in a fibre channel network having a switch element coupled to an arbitrated loop, the method comprising:

detecting an orphaned CLS primitive in the loop;

enabling a remove CLS primitive feature; and

removing the orphaned CLS primitive by replacing it with a Current Fill Word.

5. The method of claim 4, wherein the step of detecting an orphaned CLS primitive includes a switch element port sending an open (OPN) primitive to itself and if a CLS primitive is received within a loop latency period then it is classified as an orphan.

6. The method of claim 5, wherein the orphaned CLS primitive is removed by the switch element by enabling a firmware based removal feature.

7. The method of Claim 4, wherein by removing the CLS primitive traffic disruption is minimized.

8. A switch element coupled to an arbitrated loop in a fibre channel network, the switch element for detecting orphaned close CLS) primitives, the switch element comprising:

a port for arbitrating for ownership of the arbitrated loop and for sending an open (OPN) primitive to its own arbitrated loop physical address (AL_PA) to open a connection with itself, the port being further for determining if a CLS primitive is received within a loop latency period;

wherein if the port receives a CLS primitive within the latency period then the CLS primitive is classified as an orphan, and the latency period is either set at a desired value or determined.

9. The switch element of claim 8, further comprising firmware for enabling a remove CLS primitive feature and for replacing the orphan CLS primitive by a current fill word.

10. The switch element of claim 8, wherein the firmware inhibits sending a response to the orphan CLS primitive.

16. The switch element of claim 8, wherein the latency period is determined by counting the time it takes for a primitive sent by the port to itself to traverse the loop.

11. A fibre channel based network, comprising:

a switch element coupled to an arbitrated loop, the switch element for detecting orphaned CLS primitives, wherein the switch element includes a port for ownership of the arbitrated loop and for sending an open (OPN) primitive to its own arbitrated loop physical address (AL_PA) to open a connection with itself, the port being further for determining if a CLS primitive is received within a loop latency period; and

wherein if the port receives a CLS primitive within the latency period then the CLS primitive is classified as an orphan, and the latency period is either set at a desired value or determined.

12. The switch element of claim 11, further comprising firmware for enabling a remove CLS primitive feature and for replacing the orphan CLS primitive by a current fill word.

13. The switch element of claim 11, wherein the firmware inhibits sending a response to the orphan CLS primitive.

17. The switch element of claim 11, wherein the latency period is determined by counting the time it takes for a primitive sent by the port to itself to traverse the loop.