Routing packets based on congestion metric thresholds and weights

A non-transitory machine readable storage medium comprising instructions that, when executed by at least one processor, cause the at least one processor to:

• receive a packet at a network device of a plurality of network devices in a network, wherein the packet is to be routed to a destination network device;
• determine a plurality of candidate routes for the packet to be routed to the destination network device;
• assign the plurality of candidate routes to either a first group of candidate routes or a second group of candidate routes, wherein each of the candidate routes of the second group have an associated hop count greater than the hop count of any of the candidate routes of the first group;
• select the first group or the second group based on a congestion metric value associated with the first group;
• select a candidate route from the selected first group or second group based on a congestion metric value associated with the selected candidate route;
• and
• select an egress port associated with the selected candidate route.

An apparatus comprising:

• at least one ingress port through which a packet is received;
• a plurality of egress ports;
• and
• a routing engine to:
• determine a plurality of candidate routes for the packet to be forwarded to the destination network device;
• assign the plurality of candidate routes into a plurality of groups based on hop counts associated with the candidate routes;
• select a given group of the plurality of groups based on congestion metric values associated with the candidate routes;
• for the given group, select a candidate route of the given group based on a weight metric value associated with the selected candidate route;
• and
• select an egress port of the plurality of egress ports associated with the selected candidate route.