Using a reverse proxy shouldn't do that. I use plex with a reverse proxy (nginx) and don't have that problem. It sounds like a docker network configuration issue. I would guess you probably made the docker use a private network and traffic from your host to docker is being masqueraded as host IP. Make sure you're using host network mode on your docker as the other poster said.

Make sure your nginx is also passing X-Forwarded-For header to plex. This header contains information on origin IP.

Also you should enable Websockets support as Plex supports that for some web features.

I agree this is likely some weird network config on the docker level. You can prove that for a fact by taking a second machine and creating a Plex server on it. Set up the reverse proxy to send traffic to that machine. Then see what the traffic looks like. If everything comes back all clear then you know it’s definitely dockerization causing it. If it still breaks, you can rule docker out as the problem and start looking elsewhere in the stack.

Hi there. I'm a bit lost on this. Same thing happening and since it's local my remote speed limit impacted

As someone else mentioned, you need to make sure your reverse proxy sets extra headers (X-Real-IP, X-Forwarded-For) and allow websockets. That should fix your issues with Plex

Edit your Plex proxy host setting in NPM and add this line to the advanced tab.

real_ip_header CF-Connecting-IP;  

This should let the real IP through to Plex.

This is only for if you're using Cloudflare as a proxy. CF-Connecting-IP is a CloudFlare specific header.

I think you're just missing a header setting to forward the original (remote) IP as the IP making the request. Perhaps:

proxy_set_header  X-Real-IP $remote_addr;

Edit: Also possibly

proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;

Plex is technically correct. Since the device is connecting via the reverse proxy the traffic is actually local, because the traffic is coming to the Plex server from the reverse proxy on your local LAN.

an easy fix would be to not use the reverse proxy and have them go via plex web? is there a problem with doing it that way?

Probably doing this to get around CGNAT or something.

Sometimes it’s fun to do things on computer