HA iPerf upload to public server fails but LAN tests fine and Windows test to public server does too, anyone any idea?

Configuration
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Hi,

TL;DR;
Does anyone know the parameters given in the iPerf integration, cause I lack the skills to figure it out from the source at GitHub.

Full story:
I configured iPerf on my fully updated** RPi4. As a test I’ve set my Windows client as a iPerf server and it works as expected. However, when I select a public server the upload remains unknown*… When I test the public server using my Windows 10 client, both directions work just fine:

 .\iperf3.exe -4 -c speedtest.novoserve.com -p 5201
 .\iperf3.exe -4 -c speedtest.novoserve.com -p 5201 --reverse

So in summery, the integration works fine, at least technically, and the public server also allows testing up- and downstream. This made me think:

  1. the integration gives an instruction that isn’t understood/accepted by speedtest.novoserve.com
  2. the control message requires an open port that isn’t, aka my NAT router is blocking something

The logging from my ISP NAT router however is insufficient to debug from there. So I checked the source at GitHub, hoping to figure out the parameters given by the integration. I unfortunately wasn’t able to do so. So I wonder if there is anyone that can help me troubleshoot by sharing or:

  1. the instructions the integration uses,
  2. a known good public iPerf server that I can test with using HA, so I can eliminate my router/network,
  3. info on required port forwards/open ports,
  4. any other info that you think is useful

As always, I will report back my findings and possible solutions, so they are available for others.

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*The only log that I can find on my HomeAssistant installation is this:

Logger: homeassistant.components.iperf3
Source: components/iperf3/__init__.py:191
Integration: Iperf3 (documentation, issues)
First occurred: 11:25:38 (1 occurrences)
Last logged: 11:25:38

Iperf3 error: unable to send control message:

Core log:
2022-01-05 11:25:38 ERROR (SyncWorker_2) [homeassistant.components.iperf3] Iperf3 error: unable to send control message:

** Core: core-2021.12.8; Version: supervisor-2021.12.2; Operating System: Home Assistant OS 7.1

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A one-time push to visibility in the hope that someone who has an answer will see it.

3

same issue here. how to fix this problem?

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