Why can I connect to a Moonraker on port 80?

[AndreKR]

I have two Moonraker instances on my Klipper machine, one on http://192.168.0.36:7125 and one on http://192.168.0.36:7125. I have both set up in fluidd with the mentioned addresses and I can switch between them. I can see in the dev tools that fluidd opens a websocket connection to ws://192.168.0.36:7125 or ws://192.168.0.36:7126 respectively. All great.

What confuses me: I have a third entry in my fluidd hosts: http://192.168.0.36. When I select it, I can see how fluidd opens a websocket connection to ws://192.168.0.36 (port 80) and somehow a Moonraker answers! (I think it's the one that actually runs on 7125.)

What gives?

[pedrolamas]

That is because port 80 is being served by Nginx, so it can redirect specific paths to other places (in this case, to other Moonraker instances)!

For example, Moonraker use paths like /server, so that path is mapped to a Moonraker instance on 7125.