Establishing a Connection Mavlink and Ground Control Softwares Over LAN

Hi everyone,

I have two device one of them is running Linux Ubuntu 16.04 and the other windows 10. What I am trying to do is to build the Ardupilot software on my Ubuntu running device and connect to it via Mission Planner or QGroundControl that is running on my other device (Windows 10) which these two devices are on the same local network, Ubuntu’s IP is 172.16.103.135 and Windows’ is 172.16.101.129 (172.16.100.0/22).
I’ve tried to type "add output 172.16.103.135:xxxxx in terminal) and then try to connect back from mission planner and Qgroundcontrol but it didn’t work.

here I am sshing into my linux device on the left side of the image and trying to connect to it from QGroundControl but the connection isn’t established.
Can anyone help me figure what I’ve done wrong out because technically, it should work, shouldn’t it?

Thanks in advance,
Jabbar

Start here: https://ardupilot.org/dev/docs/using-sitl-for-ardupilot-testing.html#connecting-other-additional-ground-stations