How to Set Up a Minecraft Java Server on Linux

Requirements

• Minimum 2 GB RAM (4 GB for 10–20 players, 8 GB for 50+ players)
• 2+ vCPUs (high single-core frequency matters more than core count)
• Ubuntu 22.04 LTS
• Java 21 (required for Minecraft 1.20+)

Step 1: Install Java 21

apt update
apt install openjdk-21-jre-headless -y
java -version   # Should show "openjdk 21"

Step 2: Create a Dedicated System User

useradd -r -m -d /opt/minecraft -s /bin/bash minecraft
mkdir -p /opt/minecraft/server
chown -R minecraft:minecraft /opt/minecraft

Step 3: Download the Minecraft Server JAR

cd /opt/minecraft/server
# Get the latest JAR from https://www.minecraft.net/en-us/download/server
sudo -u minecraft wget -O server.jar   https://launcher.mojang.com/v1/objects/latest/server.jar

Step 4: Accept the EULA

sudo -u minecraft bash -c "java -Xmx512M -jar /opt/minecraft/server/server.jar nogui;   echo 'eula=true' > /opt/minecraft/server/eula.txt"

Step 5: Configure server.properties

nano /opt/minecraft/server/server.properties

server-port=25565
max-players=20
difficulty=normal
gamemode=survival
online-mode=true
motd=§aMy Power Down Server
view-distance=10
simulation-distance=8

Step 6: Create a systemd Service

cat > /etc/systemd/system/minecraft.service << EOF
[Unit]
Description=Minecraft Java Server
After=network.target

[Service]
User=minecraft
WorkingDirectory=/opt/minecraft/server
ExecStart=/usr/bin/java -Xms2G -Xmx4G \
  -XX:+UseG1GC \
  -XX:+ParallelRefProcEnabled \
  -XX:MaxGCPauseMillis=200 \
  -XX:G1NewSizePercent=30 \
  -jar server.jar nogui
ExecStop=/usr/bin/screen -S minecraft -X stuff "stop
"
Restart=on-failure
RestartSec=5

[Install]
WantedBy=multi-user.target
EOF

systemctl daemon-reload
systemctl enable minecraft
systemctl start minecraft

Step 7: Open the Port in UFW

ufw allow 25565/tcp

Monitor and Manage

systemctl status minecraft          # Check status
journalctl -u minecraft -f          # Live logs
systemctl restart minecraft         # Restart server
systemctl stop minecraft            # Stop server