iPerf and Port Forwarding WAN and LAN

I'll do my best to explain this setup correctly I have my iPerf server listening on port 5201 IP of the pc running the server is 10.xxx.xxx.131 PC is connected to a modem (default gateway 10.xxx.xxx.129) Modem is connected to a router (WAN 10.xxx.xxx.134 and LAN default gateway of 192.168.1.1) Behind the router are my client devices (192.168.1.xxx) running iPerf and trying to connect to the server. I am trying to port forward but not able to find the correct solution. Port Forwarding Options (on router): External Port: Internal Port: Protocol: TCP+UDP Loopback: iPerf on Client device: Server A

Question by bgardne7 on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.