In my opinion, some examples of near LOS (nLOS) would be you can still see part of the transmission tower from the client radio… so maybe there’s a tree branch, or a post, telephone pole, etc. in the way.
Non LOS (NLOS) would be a complete blockage of LOS from the transmission tower to the client. This could be a single tree, a building, a hill, etc.
Radios don’t know or report if the RF path or signal is being attenuated by nLOS or NLOS factors. They only metric that they report that might be of value is the receive signal strength indicator (RSSI). One can make an educated guess as to the LOS conditions by looking at the radio’s RSSI’s and comparing it to a predictive reference point like cnHeat or LinkPlanner. That being said, there are other issues that can reduce or skew RSSI values… like the antennas being misaligned, snow/ice on the antenna’s radome, damaged/loose RF connectors or connectors with water in them, etc.
In any case, when in doubt, it’s always a good idea to model the link path using something like cnHeat or LinkPlanner, and then compare that to what you’re actually seeing in the field, and then make adjustments as needed.