Forward port (80) to another local network IP

Question

I have a Rpi, which is behind NAT (4G carrier), but I've managed to expose ports to be accessible from the internet using https://www.remot3.it. I want to use the Rpi as proxy, so I can access a IP Webcam which is in the same LAN as the PI.

The IP Cam is providing web interface on port 80.

How to use the Pi to forward PI:81 connections to IPCAM:80?

Answer 1

Unless the PI is also the default gateway for the camera, you should use some connection forwarding like xinetd or rinetd or socat.

To configure xinetd, create a file /etc/xinet.d/camera_forward and restart xinetd:

service camera_forward
{
    disable         = no
    type            = UNLISTED
    socket_type     = stream
    protocol        = tcp
    port            = 81
    user            = nobody
    wait            = no
    redirect        = camera 80
}