CnCNet Docker Tunnel Server

This repository contains a Dockerfile to create a CnCNet tunnel server in Docker, using the prebuilt cncnet-server binary.

A tunnel server relays game traffic to help players connect to each other for online multiplayer in classic Command & Conquer titles (and other CnCNet-supported games).

Important

This image is based on the older cncnet-server binary and now-deprecated runtimes — it pulls a build that depends on .NET 6 (end-of-life) and is pinned to Ubuntu 22.04.

For new deployments, use the actively maintained .NET Core tunnel instead: CnCNet/cncnet-docker-dotnetcore-tunnel (.NET 8/9/10, configurable via environment variables, prebuilt images).

This repo is kept for reference and existing setups.

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Quick Start (Prebuilt Image)

The image is automatically built and published to the GitHub Container Registry, so you can pull and run it directly — no need to clone this repo or build anything:

Image
ghcr.io/cncnet/cncnet-docker-tunnel:latest

docker run -d --name my-tunnel-server \
    -p 50000:50000/tcp \
    -p 50000:50000/udp \
    -p 50001:50001/tcp \
    -p 50001:50001/udp \
    -p 8054:8054/udp \
    -p 3478:3478/udp \
    --cap-add=NET_RAW --cap-add=NET_ADMIN \
    --restart unless-stopped \
    ghcr.io/cncnet/cncnet-docker-tunnel:latest

Your server will appear in the CnCNet tunnel list under the default name "My CnCNet tunnel". To use your own name (or other options) without rebuilding, override the start command at run time — append it after the image name:

docker run -d --name my-tunnel-server \
    -p 50000:50000/tcp -p 50000:50000/udp \
    -p 50001:50001/tcp -p 50001:50001/udp \
    -p 8054:8054/udp -p 3478:3478/udp \
    --cap-add=NET_RAW --cap-add=NET_ADMIN \
    --restart unless-stopped \
    ghcr.io/cncnet/cncnet-docker-tunnel:latest \
    ./cncnet-server --name "My Custom Tunnel Name" --maxclients 200 --port 50001 --portv2 50000

Prefer to build the image yourself (e.g. to bake in your own tunnel options)? Follow the steps below instead.

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Getting Started (Build It Yourself)

1. Clone this repo to your server

git clone https://github.com/CnCNet/cncnet-docker-tunnel.git
cd cncnet-docker-tunnel

2. (Optional) Edit your tunnel options

The server is launched by the final CMD line in the dockerfile. Edit it to set your server name and any other options:

CMD ./cncnet-server --name "My CnCNet tunnel" --maxclients 200 --port 50001 --portv2 50000 > cncnet-server.log 2>&1 && tail -f cncnet-server.log

3. Build the Docker image

Replace my-tunnel-server with a name that helps you identify your container:

docker build -t my-tunnel-server .

4. Run your new container with the below:

docker run -d --name my-tunnel-server \
    -p 50000:50000/tcp \
    -p 50000:50000/udp \
    -p 50001:50001/tcp \
    -p 50001:50001/udp \
    -p 8054:8054/udp \
    -p 3478:3478/udp \
    --cap-add=NET_RAW --cap-add=NET_ADMIN \
    --restart unless-stopped \
    my-tunnel-server

Tunnel Options

You can edit your dockerfile (or the run-time command) to pass extra options to cncnet-server. Common options:

Option	Description	Default
--name	Name shown in the CnCNet tunnel list	My CnCNet tunnel
--maxclients	Maximum number of concurrent clients	200
--port	V2 tunnel port	50001
--portv2	V3 tunnel port	50000

So your dockerfile run command may end up looking like:

CMD ./cncnet-server --name "CnCNet UK | cncnet.org" --maxclients 200 --port 50001 --portv2 50000 > cncnet-server.log 2>&1 && tail -f cncnet-server.log

For example, to change the server name shown in the tunnel list.

Ports

Port	Protocol	Purpose
50000	TCP/UDP	Tunnel V3
50001	TCP/UDP	Tunnel V2
8054	UDP	P2P / STUN
3478	UDP	P2P / STUN

Make sure these ports are open in any firewall or cloud security group in front of your server.

Using Docker Compose (Optional)

For easier management, you can run the prebuilt image with a docker-compose.yml:

services:
  cncnet:
    image: ghcr.io/cncnet/cncnet-docker-tunnel:latest
    container_name: cncnet-server
    restart: unless-stopped
    command: ./cncnet-server --name "MyTunnel" --maxclients 200 --port 50001 --portv2 50000
    ports:
      - "50000:50000/tcp"
      - "50000:50000/udp"
      - "50001:50001/tcp"
      - "50001:50001/udp"
      - "8054:8054/udp"
      - "3478:3478/udp"
    cap_add:
      - NET_RAW
      - NET_ADMIN

Then bring it up with:

docker compose up -d

Logs

The server writes its output to /app/cncnet-server.log inside the container (not to the container's stdout, so docker logs will be empty). To view or follow it:

docker exec my-tunnel-server tail -f /app/cncnet-server.log

Sponsored by

The CnCNet tunnel server software is a CnCNet project. CnCNet is sponsored by DigitalOcean.