How to Setup Minecraft Multiplayer Server on Ubuntu 16.04

Minecraft is very popular sandbox game that is played by kids and grownups across entire globe. In this article we will show how to install a Minecraft server to play Minecraft with your friends in your own virtual world. You would need to buy the Minecraft game, to play it, and your friends will need also. Game is written in Java so it can be played on Linux, macOS or Windows. We are going to install server on Ubuntu and play the game also on Ubuntu. Server will be installed on cloud node (say digitalocean, aws, linode and rackspace), and not on localhost, although you can also do it on localhost. In that case it will be probably accessible only in your home network unless you have public IP.

How to Install Minecraft Server

First of all we need to install Java. The Minecraft documents recommend Sun JDK 6 but that is fairly outdated and since then OpenJDK have become de facto standard, so we can use OpenJDK 8 and sidestep proprietary Oracle JDK. So lets install it:

sudo apt install openjdk-8-jre

In order to achieve better security, it is advisable to not run Minecraft server as root user. So we will create a minecraft user and add it to minecraft group

adduser minecraft

groupadd minecraft

usermod -a -G minecraft minecraft

After this have been done we can log in as minecraft user in order to install the minecraft server

su minecraft

We would also need to cd to home because we donw want minecraft user to download to root directory, he has no write rights there.

cd

And next we download the current version (1.10.2 ) of minecraft server

wget https://s3.amazonaws.com/Minecraft.Download/versions/1.10.2/minecraft_server.1.10.2.jar

We will rename the server in such a way that it removes the version number. This is done so you can easier update it later, simply by swaping the binary.

mv minecraft_server.1.10.2.jar minecraft_server.jar

Next we can start the server for the first time:

java -Xmx1024M -Xms1024M -jar minecraft_server.jar nogui

This first run will be unsucessful because we need to accept the EULA. The first run have created eula.txt file which we now need to edit to accept EULA. This command will do the trick

sed -i.orig 's/eula=false/eula=true/g' eula.txt

Next we can run it again.

java -Xmx1024M -Xms1024M -jar minecraft_server.jar nogui

After this server should start and you can type the ip address of your server in the game to connect.

Connecting to the server

Now that we have server up and running, we need to get our game to connect. As mentioned, we assume that you bought the game, we will not tell you how to get the game for free and we don't know if that is even possible. If you bought the game, you will have the multiplayer option unlocked, and that is what you need to connect to the server. In order to test we bought license for $26.95 and you can download them any number of times from any number of computers. If you didn't already do so, download the latest client from Minecraft official site. Add executable bit to the file

chmod +x minecraft.jar

Next you can double-click on the jar file or right click it and select it to be started with OpeJDK. There you type credentials of your account  that you used to buy the game

After entering your user name and password, you should be presented with next screen

After entering multiplayer, there are normally no servers there. We need to add the server we just set up.

Adding server is easy, just enter ip address. And Server Name can be any, that is just how server is called on the list.

After we add server it will show up on the list and next we can connect to it. After we connect to the game, the the server console should display following message

[Server thread/INFO]: LinoxideBlaster joined the game

Off course your username would be different.

after you finished playing, and exited, the console will show something similar to this:

[Server thread/INFO]: LinoxideBlaster left the game

Making a systemd unit file

After seeing that all works well, you want to close the terminal window with SSH session on the server. But that will turn off the Minecraft server as well, as it is running in foreground mode. So we need a startup script which will make it run in background and start with the system. So lets make one.

First we need to close previous instance of the Minecraft server that ran in foreground. Just press Ctrl-C and it will close. Next we need to login as root.

su

Lets then make new file, that will become our script

nano /etc/systemd/system/minecraft-server.service

There we will paste this:

[Unit]
Description=start and stop the minecraft-server

[Service]
WorkingDirectory=/home/minecraft
User=minecraft
Group=minecraft
Restart=on-failure
RestartSec=20 5
ExecStart=/usr/bin/java -Xms1536M -Xmx1536M -jar minecraft_server.jar nogui

[Install]
WantedBy=multi-user.target
Alias=minecraft.service

Next we can start the service:

systemctl start minecraft-server.service

And enable it at system startup

systemctl enable minecraft-server.service

Conclusion

So we created our own server for Minecraft on Ubuntu. This game is addictive enough and can burn you a lot of time so be sore to forget about your chores while playing it. As for hardware requirements, Mojang site lists this

• CPU: Intel Pentium D or AMD Athlon 64 (K8) 2.6 GHz.
• RAM: 2GB.
• GPU (Integrated): Intel HD Graphics or AMD (formerly ATI) Radeon HD Graphics with OpenGL 2.1.
• GPU (Discrete): Nvidia GeForce 9600 GT or AMD Radeon HD 2400 with OpenGL 3.1.
• HDD: At least 200MB for Game Core and Other Files.
• Java 6 Release 45.

I have been playing it without trouble on Thinkpad X220T with Intel sandy Bridge HD3000 graphics, and my cousin have reported trouble on windows with Radeon Mobility 2400 which is bare minimum, according to Mojang. It is not really demanding game. So happy playing and have a nice day.