Passing correct external remote address (REMOTE_ADDR or HTTP_X_REAL_IP) to webservers behind the proxy

[filmo]

HI, I'm trying to get the actual remote IP address attached to the headers that my webserver is seeing. I'm new to all this and experimenting with a home lab to learn.

My set up is as follows:

1. Internet comes in to a Peplink Router set up as 192.168.2.1
2. That router provides port forwarding of 80 and 443 to a container running NginxProxyManager (NPM) on a ProxMox VE. The IP address of the NPM is 192.168.2.2
3. NPM then forwards the domain requests like 'https://www.mydomain.com' to my webserver located at 192.168.2.90 (a VM running also running on Promox VE)

Here's an illustration:

That all works fine and the websites listed as hosts in NPM are routed correctly to my various servers on my LAN.

However, when I dump the headers from a web request at 192.168.2.90 I get the following:
[REMOTE_ADDR] => 192.168.2.2 <<== The IP address of the NgnixProxyManager
[SERVER_PORT] => 443
[SERVER_ADDR] => 192.168.2.90
[SERVER_NAME] => www.mydomain.com
[HTTP_X_REAL_IP] => 192.168.2.1 <<=== The IP address of my router
[HTTP_X_FORWARDED_FOR] => 192.168.2.1

I do not have any advanced configurations set up on NPM (Edit Host->Advanced). It seems like NPM thinks the router is the 'real ip' address. What I would like to recover in the headers is the actual external IP address of the client making a request to the server.

If I bypass NPM and directly forward 80 and 443 to the webserver at 192.168.2.90, then REMOTE_ADDR contains the correct external IP address that is making the request. Thus when the Router forwards the request to the forwarded port, the information is present. When I put NPM in the loop, that original REMOTE_ADDR information forwarded from the router is lost when the request gets rerouted by NPM.

I would like the received header to either have REMOTE_ADDR or HTTP_X_REAL_IP be the correct external IP address.

My guess is that this is something simple that I just don't understand yet about configuring NPM. Any help is appreciated. If this has been covered in some other post that I didn't find, please feel free to redirect me.

Thank you.

[filmo]

I'm a dope. I was testing from within the internal LAN. When I tested from an externally device with it's own IP address it works as expected.

When I pinged my test script on the webserver from client on the external internet, the HTTP_X_REAL_IP was set correctly. When testing from machines on my internal LAN, the router was not passing my test machines IP address.