Link health determination

A first data link and a second data link are established between two endpoints. For each of the first and second data links, a first metric is determined based on a first scaling factor for characterizing how quickly link health degrades over time, and a time at which a most recent packet was received on the respective data link. A second metric indicative is determined based on a second scaling factor for controlling how often to probe the first and second data links in addition to regular traffic. Based on the first and second metrics, one of the first or second data links is selected for sending a data packet.