System and method for primary switch election in peer groups
View Patent ↗A system and method for primary switch election in peer groups includes a switch. The switch includes a control unit, first ports coupling the switch to a peer switch via first network links forming an inter-chassis link (ICL), and second ports coupling the switch to a plurality of first switches using a plurality of second network links. The second network links are part of a plurality of virtual link trunking (VLT) link aggregation groups (LAGs) wherein each of the VLT LAGs is associated with a respective one of the first switches. The control unit is configured to exchange dynamic election criteria with the peer switch, determine whether the switch is a primary or a secondary switch based on the exchanged dynamic election criteria, determine whether the ICL is down, and shut down the second network links when the ICL is down and the switch is the secondary switch.
1. A network switching device, the device comprising:
a controller;
one or more first ports coupling the network switching device to a peer network switching device via one or more first network links, the first network links forming an inter-chassis link (ICL); and
a plurality of second ports coupling the network switching device to a plurality of first network switching devices using a plurality of second network links, the second network links being part of a plurality of virtual link trunking (VLT) link aggregation groups (LAGs) wherein each of the VLT LAGs is associated with a respective one of the first network switching devices;
wherein the controller is configured to:
exchange dynamic election criteria with the peer network switching device;
determine whether the network switching device is a primary network switching device or a secondary network switching device based on the exchanged dynamic election criteria, wherein when the exchanged dynamic election criteria does not allow the controller to determine whether the network switching device is the primary network switching device or the secondary network switching device, exchange static election criteria with the peer network switching device and determine whether the network switching device is the primary network switching device or the secondary network switching device based on the exchanged static election criteria;
determine whether the ICL is down; and
shut down the second network links when the ICL is down and the network switching device is the secondary network switching device.
2. The device of claim 1 , wherein the exchanged dynamic election criteria includes one or more bandwidth capacities associated with the VLT LAGs.
3. The device of claim 2 , wherein the controller determines that-the network switching device is the primary network switching device when the bandwidth capacities associated with the network switching device are higher than the bandwidth capacities associated with the peer network switching device.
4. The device of claim 2 , wherein the controller determines the network switching device is the primary network switching device when an aggregation of the bandwidth capacities associated with the network switching device are higher than an aggregation of the bandwidth capacities associated with the peer network switching device.
5. The device of claim 2 , wherein the controller determines that the network switching device is the primary network switching device when a lowest one of the bandwidth capacities associated with the network switching device and a first one of the VLT LAGs is higher than a lowest one of the bandwidth capacities associated with the peer network switching device and a second one of the VLT LAGs.
6. The device of claim 1 , wherein shutting down the second network links further includes shutting down the second ports by the controller.
7. The device of claim 1 , wherein link management network traffic is exchanged after shutting down the second network links.
8. The device of claim 1 , wherein the exchanged static election criteria includes one or more selected from a group consisting of medium access control addresses, internet protocol addresses, and network switching device identifiers.
9. The device of claim 1 , wherein the exchanged dynamic election criteria includes one or more selected from a group consisting of counts of a number of second network links that are up, processor utilizations, memory utilizations, and latency measures.
10. The device of claim 1 , wherein the controller is further configured to:
exchange additional dynamic election criteria with the peer network switching device; and
determine whether the network switching device is the primary network switching device or the secondary network switching device further based on the additional exchanged dynamic election criteria.
11. A method of managing a switch, the method comprising:
periodically exchanging dynamic election criteria with a peer switch coupled to the switch via an inter-chassis link (ICL), wherein exchanging dynamic election criteria comprises exchanging one or more bandwidth capacities associated with network links;
periodically determining whether the switch is a primary switch or a secondary switch based on the exchanged dynamic election criteria, wherein when the exchanged dynamic election criteria does not allow the determination of the switch, exchanging static election criteria with the peer switch and determining whether the switch is the primary switch or the secondary switch based on the exchanged static election criteria, and wherein the exchanged static election criteria includes one or more selected from a group consisting of medium access control addresses, internet protocol addresses, and network switching device identifiers;
determining whether the ICL is down; and
shutting down a plurality of network links when the ICL is down and the switch is the secondary switch, wherein the plurality of network links are part of a plurality of virtual link trunking (VLT) link aggregation groups (LAGS), and wherein each of the VLT LAGS is associated with a respective first switch.
12. The method of claim 11 , wherein determining whether the switch is the primary switch or the secondary switch comprises determining whether the bandwidth capacities associated with the switch are higher than the bandwidth capacities associated with the peer switch.
13. The method of claim 11 , wherein determining whether the switch is the primary switch or the secondary switch comprises determining whether an aggregation of the bandwidth capacities associated with the switch are higher than an aggregation of the bandwidth capacities associated with the peer switch.
14. The method of claim 11 , wherein determining whether the switch is the primary switch or the secondary switch comprises determining whether a lowest one of the bandwidth capacities associated with the switch and a first one of the VLT LAGs is higher than a lowest one of the bandwidth capacities associated with the peer switch and a second one of the VLT LAGs.
15. An information handling system comprising:
a peer group comprising:
a first switch;
a second switch; and
an inter-chassis link (ICL) coupling the first switch and the second switch;
wherein:
the first switch is coupled to a plurality of third switches using a plurality of first network links, the first network links being organized into a plurality of virtual link trunking (VLT) link aggregation groups (LAGs) wherein each of the VLT LAGs is associated with a respective one of the third switches;
the second switch is coupled to the plurality of third switches using a plurality of second network links, each of the second network links being included in a corresponding one of the VLT LAGs;
the first switch and the second switch are configured to:
exchange one or more bandwidth capacities associated with the first network links and the second network links;
elect one of the first switch and the second switch as a secondary switch based on the exchanged bandwidth capacities, wherein when the exchanged bandwidth capacities does not allow the election of the secondary switch, exchange static election criteria and elect one of the first switch and the second switch as the secondary switch further based on the exchanged static election criteria, and wherein the exchanged static election criteria includes one or more selected from a group consisting of medium access control addresses, interne protocol addresses, and switch identifiers;
determine whether the ICL is down;
when the ICL is down and the first switch is the secondary switch, the first switch is further configured to shut down the first network links; and
when the ICL is down and the second switch is the secondary switch, the second switch is further configured to shut down the second network links.
16. The information handling system of claim 15 wherein the first switch and the second switch are further configured to elect the second switch as the secondary switch based on whether an aggregate bandwidth capacity associated with the first network links is larger than an aggregate bandwidth capacity associated with the second network links.