Spanning tree protocol enabled N-node link aggregation system

• US 10,397,099 B2
• Filed: 05/03/2017
• Issued: 08/27/2019
• Est. Priority Date: 05/03/2017
• Status: Active Grant

• Current Assignee: Dell Products LP (Dell Technologies Inc.)
• Original Assignee: Dell Products LP (Dell Technologies Inc.)
• Inventors: Subramanian, Saye Balasubramaniam, Muthukaruppan, Senthil Nathan
• Primary Examiner(s): Zhao, Wei
• Application Number:
  US15/586,088
• Publication Number:
  US 20180324089A1
• Time in Patent Office: 846 Days
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/245 Link aggregation, e.g. trunking
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A spanning tree enabled n-node VLT system includes the STP running on VLT node devices that include a first VLT node device coupled to a networking device by a LAG and designated as a root bridge via the STP. A second VLT node device coupled to the networking device is part of the LAG. ICLs couple the second VLT node device to the first VLT node device. An enhanced STP engine running on the each of the VLT node devices determines that the STP has designated a first port providing one of the ICLs as a first root port, and a second port providing one of the ICLs as an alternate port. In response, the enhanced STP engine redesignates the second port as a second root port.

Claims

1. A spanning tree enabled n-node link aggregation system, comprising:

a networking device;

a plurality of link aggregation node devices, wherein a spanning tree protocol runs on each of the plurality of link aggregation node devices, and wherein the plurality of link aggregation node devices include;

a first link aggregation node device that is coupled to the networking device by at least one first link that is part of a Link Aggregation Group (LAG), wherein the first link aggregation node device has been designated as a root bridge via the spanning tree protocol; and

a second link aggregation node device that is coupled to the networking device by at least one second link that is part of the LAG;

a plurality of Inter-Chassis Links (ICLs) coupled to the second link aggregation node device; and

an enhanced spanning tree protocol engine running on the each of the plurality of link aggregation node devices, wherein the enhanced spanning tree protocol engine is configured to;

determine that a first port that is part of one of the plurality of CLs has been designated as a first root port via the spanning tree protocol;

determine that a second port that is part of one of the plurality of ICLs has been designated as an alternate port via the spanning tree protocol; and

redesignate, in response to the first port being part of one of the plurality of ICLs and designated as the first root port and the second port being part of one of the plurality of ICLs and designated as the alternate port, the second port as a second root port, wherein the redesignating the second port as the second root port prevents blocking of the plurality of ICLs via the spanning tree protocol.

2. The system of claim 1, wherein the plurality of link aggregation node devices are part of a Virtual Link Trunking fabric.

3. The system of claim 1, wherein the enhanced spanning tree protocol engine is configured to:

ensure that Media Access Control (MAC) address flushing is not invoked on any ports that are part of any of the plurality of ICLs.

4. The system of claim 1, wherein the enhanced spanning tree protocol engine is configured to:

receive a topology change notification; and

block, in response to the second port having been designated as the alternate port via the spanning tree protocol, transmission of the topology change notification on the ICL that includes the second port.

5. The system of claim 1, wherein the enhanced spanning tree protocol engine is configured to:

ensure that the spanning tree protocol running on each of the plurality of link aggregation node devices is aware of the LAG.

6. The system of claim 1, wherein the enhanced spanning tree protocol engine is configured to:

determine that at least one of the plurality of link aggregation node devices does not include a local port-channel for the LAG and, in response, create a virtual port in that link aggregation node device for the LAG.

7. The system of claim 6, wherein the enhanced spanning tree protocol engine is configured to:

transmit a control message via the virtual port.

8. An Information Handling System (IHS), comprising:

a plurality of Inter-Chassis Links (ICLs) that couple a plurality of ICL ports to a first of a plurality of link aggregation node devices that has been designated as a root bridge by via a spanning tree protocol running on each of the plurality of link aggregation node devices;

a Link Aggregation Group (LAG) that includes a plurality of LAG ports and that is coupled to a networking device;

a processing system that is coupled to the plurality of ICL ports and the plurality of LAG ports, and

a memory system that is coupled to the processing system and that includes instructions that, when executed by the processing system, cause the processing system to provide an enhanced spanning tree protocol engine that is configured to;

determine that a first ICL port of the plurality of ICL ports has been designated as a first root port via the spanning tree protocol;

determine that a second ICL port of the plurality of ICL ports has been designated as an alternate port via the spanning tree protocol; and

redesignate, in response to the first ICL port being designated as the first root port and the second ICL port being designated as the alternate port, the second port as a second root port, wherein the redesignating the second port as the second root port prevents blocking of the plurality of ICLs via the spanning tree protocol.

9. The IHS of claim 8, wherein the plurality of link aggregation node devices are part of a Virtual Link Trunking fabric.

10. The IHS of claim 8, wherein the enhanced spanning tree protocol engine is configured to:

ensure that Media Access Control (MAC) address flushing is not invoked on any of the plurality of ICL ports.

11. The IHS of claim 8, wherein the enhanced spanning tree protocol engine is configured to:

receive a topology change notification; and

block, in response to the second port having been designated as the alternate port via the spanning tree protocol, transmission of the topology change notification on the ICL that includes the second port.

12. The IHS of claim 8, wherein the enhanced spanning tree protocol engine is configured to:

ensure that the spanning tree protocol running on each of the plurality of link aggregation node devices is aware of the LAG.

13. The IHS of claim 8, wherein the enhanced spanning tree protocol engine is configured to:

determine that at least one of the plurality of link aggregation node devices does not include a local port-channel for the LAG and, in response, create a virtual port in that link aggregation node device for the LAG; and

transmit a control message via the virtual port.

14. A method for enabling a spanning tree protocol in an n-node link aggregation system, comprising:

coupling, by a link aggregation engine, a plurality of ICL ports to a first of a plurality of link aggregation node devices via a plurality of Inter-Chassis Links (ICL);

aggregating, by the link aggregation engine, at least one Link Aggregation Group (LAG) port to provide a LAG;

designating, via a spanning tree protocol running on each of the plurality of link aggregation node devices, the first of the plurality of link aggregation node devices as a root bridge;

determining, by an enhanced spanning tree protocol engine, that a first ICL port of the plurality of ICL ports has been designated as a first root port via the spanning tree protocol;

determining, by the enhanced spanning tree protocol engine, that a second ICL port of the plurality of ICL ports has been designated as an alternate port via the spanning tree protocol; and

redesignating, by the enhanced spanning tree protocol engine in response to the first ICL port being designated as the first root port and the second ICL port being designated as the alternate port, the second port as a second root port, wherein the redesignating the second port as the second root port prevents blocking of the plurality of ICLs via the spanning tree protocol.

15. The method of claim 14, wherein plurality of link aggregation node devices are part of a Virtual Link Trunking fabric.

16. The method of claim 14, further comprising:

ensuring, by the enhanced spanning tree protocol engine, that Media Access Control (MAC) address flushing is not invoked on any of the plurality of ICL ports.

17. The method of claim 14, further comprising:

receiving, by the enhanced spanning tree protocol engine, a topology change notification; and

blocking, by the enhanced spanning tree protocol engine in response to the second port having been designated as the alternate port via the spanning tree protocol, transmission or receipt of the topology change notification on the ICL that includes the second port.

18. The method of claim 14, further comprising:

ensuring, by the enhanced spanning tree protocol engine, that the spanning tree protocol running on each of the plurality of link aggregation node devices is aware of the LAG.

19. The method of claim 14, further comprising:

determining, by the enhanced spanning tree protocol engine, that at least one of the plurality of link aggregation node devices does not include a local port-channel for the LAG and, in response, creating a virtual port in that link aggregation node device for the LAG.

20. The method of claim 19, further comprising:

transmitting, by the enhanced spanning tree protocol engine, a control message via the virtual port.