Redundant host connection in a routed network

• US 9,019,976 B2
• Filed: 02/04/2014
• Issued: 04/28/2015
• Est. Priority Date: 03/26/2009
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Gupta, Somesh, Ghanwani, Anoop, Koganti, Phanidhar, Yu, Shunjia
• Primary Examiner(s): Pham, Chi H
• Assistant Examiner(s): Huang, Weibin
• Application Number:
  US14/172,683
• Publication Number:
  US 20140153385A1
• Time in Patent Office: 448 Days
• Field of Search: 370/351, 370/389, 370/392, 370/395.1, 370/396, 370/397, 370/398, 370/399, 370/395.3, 370/400, 370/401
• US Class Current: 370/401
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's
• CPC Class Codes: H04L 45/76 Routing in software-defined topologies, e.g. routing between virtual machines
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance
• CPC Class Codes: H04L 49/65 Re-configuration of fast packet switches
• CPC Class Codes: H04L 49/70 Virtual switches

Abstract

One embodiment of the present invention provides a switch. The switch includes a management mechanism and a configuration mechanism. During operation, the management mechanism is configured to operate the switch in conjunction with the partner switch as a single logical switch. The configuration mechanism is configured to assign a virtual switch identifier to the logical switch.

Claims

1. A first switch, comprising:

a processing circuitry;

a memory coupled to the processing circuitry and storing instructions which when executed cause the processing circuitry to;

form a single logical switch with a second switch, wherein the logical switch is assigned a virtual switch identifier, and wherein the first and the second switches are both allowed to forward frames destined to an end station coupled to the first and second switches via local output ports concurrently, thereby facilitating load balancing; and

mark an ingress-switch field of a frame received from the end station with the virtual switch identifier.

2. The first switch of claim 1, wherein the first switch is a layer-2 switch capable of routing without requiring the network topology to be based on a spanning tree topology.

3. The first switch of claim 1, wherein the first switch is configured to forward the frame received from the end station in a routed network.

4. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to set the cost of a link to the logical switch to be zero.

5. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to identify the virtual switch identifier in an egress-switch field of a second frame for the end station.

6. The first switch of claim 1 wherein the memory further stores instructions which when executed cause the processing circuitry to notify the second switch about the reachability of a media access control (MAC) address associated with the end station.

7. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to disassociate the end station from the logical switch upon detecting a failure of a link between the end station and the second switch.

8. The first switch of claim 1, wherein upon detecting a failure of a link between the end station and the first switch, the memory further stores instructions which when executed cause the processing circuitry to notify the second switch of the failure via an inter-switch communication channel.

9. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to advertise that the logical switch is associated with both the first switch and the second switch, thereby facilitating multi-path routing to or from a device coupled to both switches.

10. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to discard a received multicast frame corresponding to a multicast group to which the end station belongs, when:

the multicast frame'"'"'s ingress switch identifier corresponds to the virtual switch identifier;

or

the multicast frame'"'"'s ingress switch identifier is different from the virtual switch identifier and a link between the end station and the first switch is not a primary link.

11. The first switch of claim 1, wherein the memory further stores instructions which when executed cause the processing circuitry to forward a multicast frame originated from a second end station coupled to the first switch to the end station wherein the end station is in a multicast group corresponding to the multicast frame.

12. A method, comprising:

forming a single logical switch which includes a first switch and a second switch, the logical switch having a virtual switch identifier, wherein the first and the second switches are both allowed to forward frames destined to an end station coupled to the first and second switches via local output ports concurrently, thereby facilitating load balancing; and

marking an ingress-switch field of a frame received from the end station with the virtual switch identifier.

13. The method of claim 12, further comprising performing a layer-2 forwarding function without requiring the network topology to be based on a spanning tree topology.

14. The method of claim 12, further comprising forwarding the frame received from the end station in a routed network.

15. The method of claim 12, further comprising advertising to a neighbor a zero-cost link from the first switch to the logical switch.

16. The method of claim 12, further comprising identifying the virtual switch identifier in the header of an egress frame.

17. The method of claim 12, further comprising notifying the second switch about the reachability of a media access control (MAC) address associated with the end station.

18. The method of claim 12, wherein upon detecting a failure of a link between the end station and the second switch, the method further comprises disassociating the end station from the logical switch.

19. The method of claim 12, wherein upon detecting a failure of a link between the end station and the first switch, the method further comprises notifying the second switch of the failure via an inter-switch communication channel.

20. The method of claim 12, further comprising advertising that the logical switch is associated with both the first switch and the second switch, thereby facilitating multi-path routing to or from a device coupled to both switches.

21. The method of claim 12, further comprising discarding a received multicast frame corresponding to a multicast group to which the end station belongs, when:

the multicast frame'"'"'s ingress switch identifier corresponds to the virtual switch identifier;

or

the multicast frame'"'"'s ingress switch identifier is different from the virtual switch identifier and a link between the end station and the first switch is not a primary link.

22. The method of claim 12, further comprising forwarding a multicast frame originated from a second end station coupled to the first switch to the end station, wherein the end station is in a multicast group corresponding to the multicast frame.

23. A first switch means, comprising:

an inter-switch communication means for communicating with a second switch means;

a management means for operating the first switch means in conjunction with the second switch means as a single logical switch which is assigned a virtual switch identifier, wherein the first and the second switch means are both allowed to forward frames destined to an end station means coupled to the first and second switch means via local output ports concurrently, thereby facilitating load balancing; and

a frame-marking means for marking an ingress-switch field of a frame received from the end station means with the virtual switch identifier.