A guide on how to create a Modded Minecraft Server to play on with friends for free!

Introduction

In this guide, we'll be installing a Vanila Minecraft server and modify it with a MOD (= a Modification). We'll also setup and configure a Modded Minecraft Client to connect to the Modded server.

Most tutorials and guides simply point to paying services, here's how you can Mod a Mincraft server for free.

As an example, we’ll use Decocraft as the MOD for our Minecraft Java Server and Minecraft Clients. We will be using Forge as the MOD Loader and MultiMC to play with a modded client.

This guide will not work for Minecraft Bedrock edition, only for Minecraft Java edition.

1. The Server side stuff

First we’ll do the most complex part, the Server Side STUFF…

Because of versions and compatibility, we'll first choose the MOD we want and then select the compatible Minecraft server and Mod Loader version. This is important, if you do not use the correct versions, your MODs won't work.

MOD version = MOD Loader version = Minecraft version !

Tip: You can use almost any old computer as a Minecraft Server. Just install Windows or an easy Linux OS (Ubuntu or Debian) on the old computer to serve as a Server. The only requirement for it is a bit of memory, 8Gb RAM is sufficient, more RAM is always welcome.

1.1. First, we need Java

For a Minecraft Java Edition Server to work, we will need to install the Java JDK (Java Development Kit) on our OS. Don’t just install the JRE (Java Runtime Environment), you need to install the JDK on your system.

Get the Latest JDK here for your OS and install it: https://www.oracle.com/ae/java/technologies/downloads/ 

Test your Java installation using the command in a Windows CDM of Linux Shell  "java -version", it should display the version of your Java and not return an error.

1.3. Create a Vanilla Minecraft Server

For clarity; 'Vanilla' means 'without any modifications' in computer terms.

1.3.1. Download the Minecraft Server

The latest Minecraft version can be found on https://www.minecraft.net/en-us/download/server.

However, the latest version is not always compatible with the version of the MOD you want. So download the correct version of the Minecraft Java server that is compatible with your MOD version. All previous Minecraft Java servers can be downloaded via https://mcversions.net/.

Download version 1.20.1 from https://mcversions.net/download/1.20.1 

You should have downloaded file: server.jar

1.3.2. Prepare the Minecraft Server

Start the Minecraft server once using this command in CMD of Shell, this will create the required directory structure and files for the server.

java -jar server.jar nogui

You should see an Error message, this is normal. To fix this, in the directory where you started the server, edit file eula.txt and change the value false to true and save the file.

1.3.3. Configure the server

Open the file server.properties and enter the IP address and port for the server.

server-ip=192.168.1.29
server-port=25565

Optional: If you want to play with friends on a LAN with only one account, you’ll need to disable online mode:

online-mode=false

1.3.4. Start the Minecraft Server

Now start the Minecraft server a second time.

java -jar server.jar nogui

When the server completed startup, you should be able to connect to it using a Minecraft Client to test your Minecraft Java Vanilla Server. Make sure you use the correct Minecraft client version 1.20.1 using MultiMC (explained later in detail in step 2.1.).

If everyting works as expected, shut down the Minecraft server application.

Congratulation! You have now created a Modded Minecraft Server.

2. The Minecraft Client

To connect to a Modded Server, you need a client with the same Mods installed. We'll be using MultiMC as our Minecraft Client.

2.1. Install MultiMC

Download and install MultiMC from https://multimc.org/#Download.
Link a valid Minecraft Microsoft account to MultiMc.

2.2. Create a Minecraft client instance

• In MultiMC, Select Add instance

  • Install a new Vanilla version 1.20.1 - to be compatible with our server version 1.20.1.

  • Select Edit instance

    • Select Install Forge

  • Select Loader Mods

    • Add the Decocraft JAR file decocraft-3.0.0.12-beta-1.20.1-slim.jar

  • Select Settings

  • Enable the Memory section and set a higher default Maximum memory allocation to 4096 MB.

2.3. Launch your modded Minecraft client

Now you can Launch the Modded Minecraft client via the Launch button in MultiMC.

2.4. Connect to the Modded Minecraft Server

In your Modded Minecraft client, connect to the server IP:PORT of your Modde Minecraft server.

Congratulation! You connected to your own free Modded Minecraft Server.

GL HF