Docker Port forwarder

Container for forwarding incoming traffic in one port to an external server. Since the container works with iptables to set up the traffic forwarding, it requires the NET_ADMIN privilege.

The forwarding configuration is set up with environment variables. These variables define the listening port and the destination server and optionally, the destination port for the incoming traffic.

Environment Variables for setting up traffic forwarding

Variable	Description
PORT	Source port of incoming traffic
FORWARD_TO	Destination server IP or hostname to forward traffic to
FORWARD_TO_PORT	(optional) Destination port where to forward traffic on the destination server. When not defined, it defaults to the same value of $PORT
PROTOCOL	(optional) Protocol to use. Default to tcp

Examples

  docker run --name port_forwarder            \
             --cap-add=NET_ADMIN              \
             -p 80:80                         \
             -e PORT=80                       \
             -e FORWARD_TO=private.server.com \
             -e FORWARD_TO_PORT=8080          \
             topherafa/port-forwarder

Creates a container that forwards incoming traffic in port 80, to port 8080 on private.server.com.