How do I set up a MC server to restart and backup at 6am every day?

Question

So I have a mineraft server and I want to set it up so that it restarts at 6am and backs up itself too. I run the server in screen and to stop the server I have to open the screen (with screen -r) and run /stop in the MC server console. I would then like the computer to automatically copy the server world file to a backup somewhere maybe with the format PATH/TO/DIRECTORY/worldBackupDD.MM.YY/. And then after that the script would run sudo java -Xmx8G -Xms8G -jar /PATH/TO/DIRECTORY/server.jar nogui to start the server again in screen.

So what I want to do is (at 6am) stop the server, backup the server, then start the server again in screen. So how do I do this? Would I use cron? I don't really know how to set this up or how to do this in cron. Or would I do it another way? Any help would be appreciated.

(btw the server runs on ubuntu server 18.04)

Answer 1

Cron is a handy command. man cron

crontab -e

# Edit this file to introduce tasks to be run by cron.
# 
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
# 
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').# 
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
# 
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
# 
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
# 
# For more information see the manual pages of crontab(5) and cron(8)
# 
# m h  dom mon dow   command

0 6 * * * /home/yourloginname/backup.sh

---

Then create backup.sh

#!/bin/sh
command-which-stop-the-server
tar -zcf /PATH/TO/DIR/worldBackup`date "%D"`.tar /TARGET/DIR/
/PATH/TO/java -Xmx8G -Xms8G -jar /PATH/TO/DIRECTORY/server.jar nogui

Note: you must use a full path, if this needs to be executed by root, you have to run cron by the root user.
See How to set up a root cron job properly