Method and apparatus for a redundant port
A method is provided for a redundant port system in which any port in a packet-forwarding device can be designated as a redundant port for any other port. The redundant port system detects when the primary port fails or is about to fail, and activates or begins to activate the redundant port as a backup. The redundant port system switches to the redundant port by causing the switch fabric in the packet-forwarding device to fail over to the redundant port by updating the port description tables, routing tables, bridging tables, or other switch fabric components to designate the redundant port instead of the failed primary port, and forcing the failed primary port to deactivate. The redundant port system continues to monitor the primary port and reverts to the primary port as the preferred data path as soon as the primary port is capable of being reactivated.
1. A method for port redundancy comprising: designating two or more redundant ports to backup two or more primary ports, wherein the redundant and primary ports are located in the same device and any of the redundant ports may be used to backup any of the primary ports;
Activating the redundant port when a primary port fails; and
Updating a data path to use the redundant port instead of the failed port.
2. The method of claim 1 , further comprising:
reverting to the primary port when the primary port recovers, including inactivating the redundant port, activating the primary port, and updating the data path to use the primary port instead of the redundant port.
3. The method of claim 2 , further comprising:
determining when first primary port recovers using an auto-negotiation protocol.
4. The method of claim 2 , wherein activating the port includes updating a port designation in a port description table to the activated port, the port designation corresponding to the port designated for the data path.
5. The method of claim 2 , wherein updating the data path includes updating a port designation in a route table corresponding to the data path.
6. The method of claim 1 , wherein designating the redundant port to backup the primary port includes inactivating the redundant port until the primary port fails.
7. The method of claim 1 , further comprising:
determining when the primary port fails by using an auto-negotiation protocol.
8. The method of claim 1 , further comprising:
determining when the primary port fails by examining a physical layer of the primary port.
9. The method of claim 1 , further comprising:
determining when the primary port recovers by examining a physical layer of the primary port.
10. The method of claim 1 , wherein the primary port is a member of a load shared group.
11. The method of claim 10 , wherein activating the redundant port is not performed until a threshold number of ports in the load shared group fails.
12. The method of claim 10 , wherein updating the data path to use the redundant port instead of the primary port is not performed until a threshold number of ports in the load shared group fails.
13. The method of claim 1 , wherein activating the redundant port and updating the data path to use the redundant port is performed in under 1 second.
14. The method of claim 1 , wherein activating the redundant port and updating the data path to use the redundant port provides faster fail over for the data path than can be provided by a standby router protocol.
15. The method of claim 1 , wherein the primary port fails as a result of a failure in an upstream switch and the redundant port uses a different upstream switch to further provide redundancy for the data path.
16. An apparatus for port redundancy comprising:
a set of two or more primary ports;
a set of two or more redundant ports designated to backup the primary ports, wherein any of the redundant ports may backup any of the primary ports;
a switch fabric to maintain which of the primary and redundant ports is an active port for a data path; and
a link monitor to cause the switch fabric to configure the data path to use the redundant port upon detecting a failure in a link to the primary port.
17. The apparatus of claim 16 , wherein the link monitor detects failure in the link to a primary port using an auto-negotiation protocol.
18. The apparatus of claim 16 , wherein the link monitor detects failure in the link to a primary port by obtaining information from a physical layer of a primary port.
19. The apparatus of claim 16 , wherein the failure includes when the link is about to fail.
20. The apparatus of claim 16 , further comprising:
a port description table having a description of which of the primary and redundant ports is the active port for the data path.
21. The apparatus of claim 16 , wherein one or more primary ports are a member of a load shared group and the link monitor causes the switch fabric to configure the data path to use a redundant port only after detecting a failure in a threshold number of members of the load shared group.
22. The apparatus of claim 16 , wherein the link monitor causes the switch fabric to restore the active port to a primary port immediately upon detecting a recovery in the link status of the link to the primary port.
23. The apparatus of claim 22 , wherein the link monitor detects the recovery in the link status of the link to a primary port using an auto-negotiation protocol.
24. The apparatus of claim 22 , wherein the link monitor detects the recovery in the link status of the link to a primary port by examining a physical layer of the primary port.
25. The apparatus of claim 16 , further comprising:
a port configuration data, wherein the port configuration data is used to configure the active port.
26. The apparatus of claim 25 , wherein to configure the active port includes to specify how many ports are in a load shared group in which the active port is a member and a threshold number of member ports that must fail before the switch fabric is to configure the data path to use the redundant port.
27. A redundant port system comprising:
A set of two or more primary links to two or more primary ports;
A set of two or more redundant links to two or more redundant ports;
A status of each of the primary and redundant links to the primary and redundant ports;
A data path associated with one of the primary or redundant ports depending on the status of the respective links; and
A processor to cause the data path to be associated with the redundant port when the status of the primary link is failed, and to further cause the data path to be associated with the primary port when the status of the primary link has returned to normal, wherein any of the redundant ports may backup any of the primary ports.
28. The system of claim 27 , wherein the status of the primary and redundant links is determined using an auto-negotiation protocol.
29. The system of claim 27 , wherein the status of the primary and redundant links is determined by receiving a physical layer information from a media access control layer associated with the respective primary and redundant links.
30. The system of claim 27 , wherein the data path is associated with the one of the primary or redundant ports by updating a port tag in a port description table, the port tag indicating an identifier of the associated port.
31. The system of claim 27 , wherein a primary port is a member of a load shared group and wherein the processor causes the data path to be associated with the redundant port only after the status of the primary link to a threshold number of member ports is failed, and to further cause the data path to be associated with the member port when the status of the primary link to the threshold number of member ports has returned to normal.
32. The system of claim 27 , further comprising:
a port configuration data, wherein the processor causes the port configuration data to be loaded to the redundant port when the status of the primary link failed, and to further cause the port configuration data to be restored to the primary port when the status of the primary link has returned to normal.
33. An article of manufacture comprising:
A machine accessible medium including data that, when accessed by a machine cause the machine to:
designating a backup port from a set of two or more redundant ports to backup a primary ports, wherein the redundant and primary ports are located in the same device and any of the redundant ports may be used to backup any of the primary ports;
Activating the redundant port when a primary port fails; and
Configure a data path to use the redundant port instead of the failed port.
34. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
revert to the primary port when the primary port recovers, including inactivating the redundant port, activating the primary port, and reconfiguring the data path to use the primary port instead of the redundant port.
35. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
designate a redundant port to backup a primary port, where such designation includes inactivating the redundant port until the primary port fails.
36. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
determine when a primary port fails by using an auto-negotiation protocol.
37. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
determine when a primary port fails by obtaining a physical layer information from the primary port.
38. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
determine when a primary port recovers using an auto-negotiation protocol.
39. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
determine when a primary port recovers by obtaining physical layer information from the primary port.
40. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
activate the port, including updating a port designation in a port description table to the activated port, the port designation corresponding to the port designated for the data path.
41. The article of manufacture of claim 33 , wherein the machine accessible medium further includes data that causes the machine to:
configure the data path, including updating a port designation in a route table corresponding to the data path.
42. The article of manufacture of claim 33 wherein the primary port is a member of a load shared group, and wherein the machine accessible medium further includes data that causes the machine to:
activate a redundant port when a threshold number of ports in the load shared group fails.
43. The article of manufacture of claim 42 wherein the machine accessible medium further includes data that causes the machine to:
configure the data path to use the redundant port instead of the primary port when a threshold number of ports in the load shared group fails.
44. The article of manufacture of claim 33 wherein the machine accessible medium further includes data that causes the machine to:
activate the redundant port and configure the data path to use the redundant port in under 1 second.
45. The article of manufacture of claim 33 wherein the machine accessible medium further includes data that causes the machine to:
activate the redundant port and configure the data path to use the redundant port to provide faster redundancy for the data path than can be provided by a standby router protocol.