In this project a Minecraft server is installed to ubuntu by using salt state. This is the school project and the final work of the course.
In the course we have learned how to use salt state. Personally, I have had to learn more. Before the course I didn't know how to use Linux or salt. Therefore, my starting points were not good. However doing this task, I found myself understanding several things I didn’t know before the course began. I also learned to use several different salt state commands. The hardest part was coming up with a suitable topic for my work. I went through several different options and ran into problems at the beginning. For example, Obs-studio does not work through the VirtualBox that was originally intended to be installed. Eventually, I came up with a topic and spent several hours preparing to browse related videos and articles on the internet. I tried to gather all possible information to make the installation a success and the server up and running.
The test, installation and "project" has been done with Ubuntu 21.10, which I run with VirtualBox.
Before this project I have already installed a salt master and a salt minion called Teronapuri (Teroshelper).
I made directory for project /srv/salt/MCS so this is where all the files go. I also made init.sls (salt state file) there. So if you want to try this project make that directory and copy my init.sls there.
You need:
- salt master/minion
- /srv/salt/MCS folder
- init.sls file
- working internet
Before creating a salt state, we need to find out what we need to make the Minecraft server working.
Fortunately, a lot of information about this can be found on the internet. The first thing to keep in mind is java support. We need the latest possible java version to get the latest java based Minecraft server up and running. I personally used this page to help https://minecraft.fandom.com/wiki/Tutorials/Setting_up_a_server
So we need to have Openjdk version 18 installed (I tried version 16, it is not compatible)
In addition to this, we need Curl in order to upload the Minecraft server file.
- extra: We download Byobu, with Byobu we can make an extra shell window to start the server. For this reason, we can use shell normally even when the server is running. Otherwise, the server would use shell itself until we shut it down.
All of these we find using the Advanced Packaging Tool - APT
we tell the salt minion to install these programs (openjdk-18-jdk, byobu and curl)
$ /srv/salt/MCS/init.sls
install java:
pkg.installed:
- name: openjdk-18-jdk
install byobu:
pkg.installed:
- name: byobu
install curl:
pkg.installed:
- name: curl
The foundation has now been done. We have java support, we have curl and we have byobu. Next, we download the Minecraft server file itself. The file could either be downloaded using a browser or, as in this case, using salt.
download server file:
cmd.run:
- name: curl https://launcher.mojang.com/v1/objects/c8f83c5655308435b3dcf03c06d9fe8740a77469/server.jar --output /srv/salt/MCS/server.jar
- creates: /srv/salt/MCS/server.jar
curl command loads server.jar from that path. The --output option specifies the path and file name. In this case, the file is uploaded to the /srv/salt/MCS/ folder server.jar. The file path is from the official Minecraft websites.
Next, we need to create an End User License Agreement = EULA approval. So let's tell salt to make a file called eula.txt and the contents of the file: eula = true (without this the server will not start.)
eula=true file:
file.managed:
- name: /srv/salt/MCS/eula.txt
- contents:
- eula=true
Now we should have everything we need installed, created and downloaded.
Let's change the ufw settings and make a hole in the 25565/tcp port so that the friends can also join the server. Minecraft normally uses that 25565 port. (Also we make sure ufw (firewall) is on.)
ufw allow 25565:
cmd.run:
- unless: "ufw status verbose | grep '25565/tcp'"
ufw enable:
cmd.run:
- unless: "ufw status | grep 'Status: active'"
Now we should have all the necessary base work done and one can move on to see what our salt state looks like and does it work.
This is what it looks like now. Salt state which downloads the necessary programs, installs them, loads the server.jar file, creates an eula.txt file and changes the ufw settings.
Lets test our salt state!
All pkg.installed functions works. Because they were not installed salt installed them.
Server.jar downloaded successfully and the eula.txt file was created correctly.
Ufw changes were successful and ufw is on. It took almost 40 seconds due to downloads and installations. Now, however, everything should be ready!
Let's try again and see if there will be idempotence or if there are problems in the salt state.
Again, all functions work. The programs were installed in the previous run of the salt state, so now minion don't have to touch them and can move on.
Since server.jar is already downloaded, the minion is understood that the file does not need to be reloaded. Similar to the eula.txt file, the file exists. No need to make new ones.
Also, the change that was made to ufw has been noticed and does not need to be made again. ufw is also confirmed to be on. So everything should work in salt state, all that's left is to try the server itself, will it work.
Lets try to start the server with the following command:
sudo java -Xms1024M -Xmx1024M -jar /srv/salt/MCS/server.jar --nogui
Java options should be added between the java and the -jar.
-Xms (the initial memory size).
-Xmx sets how much memory the server is allowed to use.
/srv/salt/MCS/server.jar is the server location and file.
--nogui Doesn't open the GUI when launching the server.
You can also set other parameters at the start command, more instructions can be found at this link:
https://minecraft.fandom.com/wiki/Tutorials/Setting_up_a_server
So server is started and running
I also started the server using the graphical user interface.
Command byobu will start byobu shell and F6 close, but applications running in the byobu shell remain on in the background. F12 will close shell and the applications. So when you start byobun and the server there you can switch from the F6 button back to the normal shell and the server will run in the background. You can return by typing byobu again. The byobun shell is different enough to distinguish it from a normal shell.
and when you press F6 it shows it like this:
Unfortunately, even if I get the server to run and stay running it stays there. The biggest problems accessing the server can be found between the virtual machine (to)-> windows and the windows (to)-> router. In order to be able to access the server running on the virtual machine, a port forward should be created throughout the whole line. Because microsoft has made it impossible to download the trial version of the game (watch reviews from microsoft market), I'll leave the adjustment to this point. I don't own that game, and I'm not going to pay 26 euros for it because of the course. So in order for the server to be able to join and play, there would be even more adjustments still to be made. However, setting up a server was a good exercise for myself and I learned a lot from it. At the same time, I think I was able to create a successful module.
- MinecraftWiki: Tutorials/Setting up a server. https://minecraft.fandom.com/wiki/Tutorials/Setting_up_a_server
- Pezet, Don 2021: How to install a Minecraft Server on Linux - Ubuntu. https://www.youtube.com/watch?v=Yxi_If6JGTQ
- DOWNLOAD THE MINECRAFT: JAVA EDITION SERVER. https://www.minecraft.net/en-us/download/server
- CURL: Command line tool and library for transferring data with URLs. https://curl.se/
- Byobu. https://www.byobu.org/
- Karvinen, Tero 2020: Command Line Basics Revisited. https://terokarvinen.com/2020/command-line-basics-revisited/
- SaltStack 2016: Functions. (https://docs.saltproject.io/en/getstarted/config/functions.html)
- SaltStack 2016: Manage Files. https://docs.saltproject.io/en/getstarted/config/files.html
- Karvinen, Tero 2022: Configuration management systems 2022. https://terokarvinen.com/2021/configuration-management-systems-2022-spring/