Set up a Minecraft server on Linux server using systemd

Linux Minecraft Server.markdown

Set up a Minecraft server on Linux server using systemd

Set up server daemon

Make a user and group for the Minecraft server

sudo useradd -d /var/minecraft -m -r -U minecraft
sudo adduser brian minecraft
sudo chmod g+s /var/minecraft

Make the file structure

sudo su minecraft
cd ~
mkdir servers
mkdir build
mkdir build/mcrcon
cd build/mcrcon

Build a tool to send commands to the server using RCON

git clone git://git.code.sf.net/p/mcrcon/code mcrcon-code
cd mcrcon-code
gcc -std=gnu11 -pedantic -Wall -Wextra -O2 -s -o mcrcon mcrcon.c
cp mcrcon ~/

Enable RCON on the minecraft server

nano ~/servers/technic-blightfall-2.1.5/server.properties

Add the following lines

enable-rcon=true
rcon.port=25575
rcon.password=<password>

Make it unreadable to the public since it contains the RCON password

chmod 770  ~/servers/technic-blightfall-2.1.5/server.properties

Add a stop script that utilizes RCON

nano ~/servers/technic-blightfall-2.1.5/stop.sh

And add the following lines

#!/bin/bash
/var/minecraft/mcrcon -H localhost -P 25575 -p <password> stop

Make it executable, but unreadable to the public since it contains the RCON password

chmod 770  ~/servers/technic-blightfall-2.1.5/stop.sh

Exit from the su command add a firewall exception

exit
sudo ufw allow 25575

Add a daemon

sudo nano /etc/systemd/system/minecraft-blightfall.service

Paste the following in

[Unit]
Description=Blightfall Minecraft Server
Documentation=

Wants=network.target
After=network.target

[Service]
User=minecraft
Group=minecraft
Nice=5
KillMode=none

ProtectHome=true
ProtectSystem=full
PrivateDevices=true
NoNewPrivileges=true
PrivateTmp=true
InaccessibleDirectories=/root /sys /srv -/opt /media -/lost+found
ReadWriteDirectories=/var/minecraft/servers/technic-blightfall-2.1.5

WorkingDirectory=/var/minecraft/servers/technic-blightfall-2.1.5
ExecStart=/var/minecraft/servers/technic-blightfall-2.1.5/start.sh
ExecStop=/var/minecraft/servers/technic-blightfall-2.1.5/stop.sh

[Install]
WantedBy=multi-user.target

Reload and enable the daemon

systemctl daemon-reload
systemctl enable minecraft-blightfall.service

Test the daemon

systemctl start minecraft-blightfall.service
systemctl status minecraft-blightfall.service
journalctl -u minecraft-blightfall.service -f

Set up automated backups

Make a symlink to a backup drive and set necessary permissions

ln -s /path/to/backups/folder /var/minecraft/backups
sudo chown -R minecraft:minecraft /path/to/backups/folder
sudo chmod -R 770 /path/to/backups/folder

Download my Minecraft backup utility and configure it

cd /var/minecraft
wget -O mc-backup-util.jar https://github.com/thelegendofbrian/mc-server-backup-util/releases/download/v0.0.2/mc-server-backup-util-0.0.2.jar
java -jar mc-backup-util.jar
nano config.ini

Edit the config values for the following

serversDirectory=servers
backupsDirectory=backups

Test to make sure it works

java -jar mc-backup-util.jar
ls backups/*

Install cronic so you only get emailed about errors from cron tasks

sudo apt install cronic

Schedule the backup

sudo crontab -u minecraft -e

Add the following lines to back up every 12 hours and get emails about errors

MAILTO="email@domain.com"
0 0  * * * cd /var/minecraft && cronic java -jar mc-backup-util.jar
0 12 * * * cd /var/minecraft && cronic java -jar mc-backup-util.jar

Usage

View server log

journalctl -u minecraft-blightfall.service -f

Start, stop, restart server

systemctl start minecraft-blightfall.service
systemctl stop minecraft-blightfall.service
systemctl restart minecraft-blightfall.service

Open interactive prompt to send commands to the server

/var/minecraft/mcrcon -H localhost -P 25575 -p <password> -t

You didn't include what start.sh should look like

You didn't include what start.sh should look like

It entirely depends on what you're running. If it's for vanilla, it might start with something like java -jar server.jar. Mod packs often include their own script to start.