Speedtest with iperf3

Upload:

iperf3 -c speedtest.wtnet.de -p 5200

Download:

iperf3 -c speedtest.wtnet.de -p 5200 -R

Both directions together:

iperf3 -c speedtest.wtnet.de -p 5200 --bidir

Sometimes it seems not working. Retry it later or use another port. wtnet.de allows ports 5200 - 5209.