I installed a modded FTB server to my Ubuntu Server, created a user and group called "ftb", and gave it its own directory /opt/ftb/ that contains a folder with the server files. In the server folder, there is a start.sh file to start the server. How do I make a system service file so I can use commands such as systemctl status ftbacademy.service, systemctl start ftbacademy.service, and systemctl stop ftbacademy.service. Upon stopping the server I wish for it to save and then close the server. What would the .service file look like? I know it has to be placed in /etc/systemd/system/, but I don't know how to write the file that would make the ftb user open it's own virtual terminal or whatever to be able to save the world and then stop the server.

Ubuntu Server Version 20.04.3

FTB Academy 1.16 Server Files Download Site Used: https://feed-the-beast.com/modpacks/88/server/2077 I selected the Linux download option then ran the install file to automatically download the server files.

I am also using a different version of JDK to run the server file so I changed the start.sh file to this:

#!/bin/bash

if ! grep -q "eula=true" eula.txt; then

    echo "Do you agree to the Mojang EULA available at https://account.mojang.com/documents/minecraft_eula ?"

    read -N 1 -p "[y/n] " EULA

    if [ "$EULA" = "y" ]; then

        echo "eula=true" > eula.txt

        echo

    fi

fi

/usr/lib/jvm/java-11-openjdk-amd64/bin/java -javaagent:log4jfix/Log4jPatcher-1.0.0.jar -XX:+UseG1GC -XX:+UnlockExperimentalVMOptions -Xmx5000M -Xms4000M -jar forge-1.16.5-36.2.2.jar nogui