using Iperf3 to test upload and download
Solution 1:
The iperf client initiates a connection to an iperf server, and the default test is the upload speed:
$ iperf3 -c la.speedtest.clouvider.net -p 5209
Connecting to host la.speedtest.clouvider.net, port 5209
when you use the -R switch, it downloads from the server. note the 3rd line:
$ iperf3 -c la.speedtest.clouvider.net -p 5209 -R
Connecting to host la.speedtest.clouvider.net, port 5209
Reverse mode, remote host la.speedtest.clouvider.net is sending