An approach is disclosed for selecting tunnels through which network traffic can be sent to steer the traffic away from congestion hot-spots. In one embodiment, multiple Foo-over-UDP (FOU) tunnels, each having a distinct source port, are created between two endpoints. Probes are scheduled to measure network metrics, such as latency and liveliness, of each of the FOU tunnels. In turn, the network metrics are used to select particular FOU tunnel(s) to send traffic over in a manner that is fair across source and destination IP addresses of the FOU tunnel(s). In particular, scores are assigned to the source and destination IP addresses based on sums of scores assigned to tunnels having those source and destination IP addresses based on the tunnels' performance metrics. A load balancer then splits a number of buckets across the source and destination IP addresses, and ultimately across the tunnels, based on the assigned scores.