MinecraftServerProxy

Run multiple Minecraft: Java Edition servers behind a single port.

About

I created this project so I could run many Minecraft servers on one computer without needing to open a new port for each one. My end goal is to use this project to create a Minecraft server control panel that can be used to manage many Minecraft servers running in Docker (check out this awesome Docker image: https://github.com/itzg/docker-minecraft-server).

MinecraftServerProxy is inspired by other projects such as https://github.com/Ktlo/MCSHub, https://github.com/handtruth/mcshub, and https://github.com/janispritzkau/minecraft-reverse-proxy (among others).

Tools / Libraries

MinecraftServerProxy

• .NET 6.0
• Microsoft.Extensions.Hosting - MIT
• System.IO.Pipelines - MIT
• Pipelines.Sockets.Unofficial (https://github.com/mgravell/Pipelines.Sockets.Unofficial) - MIT

MinecraftServerProxyStandalone

• .NET 6.0
• Serilog (https://github.com/serilog/serilog) - Apache-2.0
• Serilog.Extensions.Hosting (https://github.com/serilog/serilog-extensions-hosting) - Apache-2.0
• Serilog.Settings.Configuration (https://github.com/serilog/serilog-settings-configuration) - Apache-2.0
• Serilog.Sinks.Console (https://github.com/serilog/serilog-sinks-console) - Apache-2.0
• Serilog.Sinks.File (https://github.com/serilog/serilog-sinks-file) - Apache-2.0

Getting Started

There are multiple ways to use MinecraftServerProxy.

• Minecraft server administrators may want to use the standalone application for their networks.
  • See Setting up the standalone application and Testing the proxy for more information
• Developers may want to integrate the MinecraftServerProxy library into their existing applications.
  • See Integrating the library for more information

Setting up the standalone application

This section assumes you've already downloaded a MinecraftServerProxyStandalone release that is appropriate for your operating system.

1. Download a MinecraftServerProxyStandalone release and default appsettings.json configuration file
   • See https://github.com/Connor14/MinecraftServerProxy/releases for pre-built downloads
2. Copy the release files and appsettings.json to the same directory
   • On Linux, copy the downloaded executable to the same directory as appsettings.json
   • On Windows, extract the downloaded release to the same directory as appsettings.json
3. If desired, modify appsettings.json to configure your proxy's settings
   • Testing the proxy will assume you are using the default appsettings.json
4. Run the MinecraftServerProxyStandalone executable

You can also run the application as a service. Here are the additional steps:

Linux Systemd

For more information, see the Microsoft Blog Post: https://devblogs.microsoft.com/dotnet/net-core-and-systemd/

1. Copy the MinecraftServerProxyStandalone.service file to /etc/systemd/system
2. Run sudo systemctl daemon-reload
3. Run sudo systemctl status MinecraftServerProxyStandalone and check output
4. Run sudo systemctl start MinecraftServerProxyStandalone.service to start the service
5. Run sudo systemctl status MinecraftServerProxyStandalone again and check output
6. Run sudo systemctl enable MinecraftServerProxyStandalone.service to start when the machine starts

Windows Service

TODO

Integrating the library

Please see MinecraftServerProxyStandalone for a full code example.

More information to come!

Testing the proxy

To test the proxy, we will use this Docker image: https://github.com/itzg/docker-minecraft-server. I assume you have Docker installed on your system.

Note: When running a Minecraft server, you must accept the Minecraft EULA before the Minecraft server software will start. The following commands accept the Minecraft EULA automatically so that the containers will start properly, but please know that this does not mean I am accepting the Minecraft EULA on your behalf. Anyways, back to testing.

1. Start two Minecraft servers on different ports.
   • The first is on port 25570
   • The second is on port 25571.

Please see the docker run documentation for more details on the following commands (https://docs.docker.com/engine/reference/run/):

# Run in a command line / terminal instance:
docker run -it -e EULA=TRUE -p 25570:25565 --name mc1 --rm itzg/minecraft-server

# Run in another command line / terminal instance:
docker run -it -e EULA=TRUE -p 25571:25565 --name mc2 --rm itzg/minecraft-server

2. Start your Minecraft: Java Edition client and navigate to the Multiplayer menu.

3. Navigate to the Multiplayer menu

   • Click Add Server
   • Enter Minecraft Server 1 as the Server Name and connor1.localhost as the Server Address
   • Click Done
   • Click Add Server again
   • This time enter the details for the second server instance: Minecraft Server 2 and connor2.localhost
   • Click Done

4. If you haven't started a MinecraftServerProxyStandalone instance yet, you will notice that neither server is responding

   • This is because you are trying to connect to connor1.localhost and connor2.localhost using the default port of 25565.
   • Your servers are running on ports 25570 and 25571 respectively.
   • This is where the proxy comes in.

5. Start MinecraftServerProxyStandalone and click Refresh in the Minecraft client. Your servers should now be acccessible.

6. Joining Minecraft Server 1 will take you to the first server while joining Minecraft Server 2 will take you to the other server.

How it works

When you join connor1.localhost in the Multiplayer menu, the Minecraft client tries to connect to the Minecraft server running on connor1.localhost:25565. There isn't a Minecraft server running at this location. The proxy is.

The proxy reads the incoming Minecraft server handshaking information and determines that the Minecraft client is trying to connect to connor1.localhost. The proxy searches the ProxyConfiguration in appsettings.json for connor1.localhost and sees that connor1.localhost is associated with 127.0.0.1:25570. The proxy sends the data from the Minecraft client to the Minecraft server running on 127.0.0.1:25570. When the proxy receives the response from the server, it returns the response to the Minecraft client.

This pattern of passing data from Minecraft client -> proxy -> Minecraft server -> proxy -> Minecraft client continues while players are connected to the server.

Future Enhancements

• Windows Service / Systemd integration
  • See https://www.nuget.org/packages/Microsoft.Extensions.Hosting.WindowsServices for Windows Services
  • See https://www.nuget.org/packages/Microsoft.Extensions.Hosting.Systemd for Systemd
  • Will need to be mindful of the current directory and location of appsettings.json

License Information

See the Tools / Libraries section above