My son and I rebuilt our LAN server with Lubuntu 20.x - WARNING: Fun ahead. :)

Tonight was a fun night of re-installing my server OS and installing Minecraft

I had a recent physical drive failure, and lost the OS of my local test server. Urgh.

I decided that it was time for a refresh anyway, since I was running Ubuntu 18. So it was off to read reviews of what is considered a decent OS for a low level mini-ITX form factor ADM motherboard.

After several reviews, I settled on lubuntu, the lightweight Ubuntu distro.
https://lubuntu.me/downloads/

I like the long-term releases, so I picked Lubuntu 20.04.

I run Ubuntu 20 as my main daily desktop. Yep, this was just going to be a base install for my server.

After downloading lubuntu-20.04.2-desktop-amd64, it was off to the races.

Rufus to the rescue...

If you've ever had to install an OS, it's so nice when you can download a .iso image and use Rufus (https://rufus.ie/) to 'burn' it onto a usb key.

Once that process was done (it only took a couple minutes), it was time to boot the server with the new OS install freshly burned onto a usb stick.

Having installed Ubuntu many times using different forks, etc. I knew the install process would be fairly straightforward. I don't need to re-invent the wheel since there are tons of great tutorials on how to install Ubuntu flavors. (I threw some links in the bottom of the post if you're interested)

A little cleaning goes a long way

I recently bought some Endust spray for electronics. While the USB image was being burned, I cleaned the inside of the case.

MAN! It's been a while since I did this, but I didn't expect that much dust.

I also wiped off the outside of the case with some wipes. Good as new!

My trusty motherboard was ready to get her new OS.

AMD Hudson M1 E350IA-E45 for those interested.

Now that the motherboard was cleaned, dusted, and ready to go, I put the usb key with Lubuntu on the machine, booted it from the Lubuntu installation, and off we went.

Since the last drive was toast, I had a new 500G SSD on hand I was able to use to install the OS.

Like most Ubuntu installation, this was one guided and gave me plenty of choices. I took the defaults and installed Lubuntu. Tweaking comes after I get it installed.

A bit about passwords

I work in IT, and have for 2 decades. Here's some advice:

1) Use complex (non-guessable passwords).

Seriously. Use complex passwords. They're much less likely to get cracked, and will keep the device more secure. I recommend using passwords with camel-case (upper and lower letters) as well as numbers and symbols.

Most passwords require some complexity.

Ubuntu is also a little different because it's Linux kernel-based OS. There's 100% freedom to create a simple or complex password.

2) Use a password keeper such as LastPass or Bitwarden to store your passwords.

If you followed the first piece of advice, you created a complex password.

The tricky part is: how do you remember it?
The answer? You DON'T.

You use a password app to store complex passwords, and the only password you need to remember is the one to allow you to access your password app. (Take backups of your password file and store it securely. That's a whole 'nother post.)

I really wish people did this. It would make my job easier. I can't tell you the amount of time I have spent waiting on high-end support calls for some software company infra dudes to fumble around searching for access or password for a server.

It doesn't have to be that way. Save your passwords. (and backup your saves)

OK, done ranting. :D

We created a separate user for one of our server processes.

Because I want some server processes to run under limited account and not my own login, I created a new separate account to use with the Minecraft server I am installing for me and my son.

This new account (user aptly named minecraft) was set up and password assigned. Now when I launch minecraft after it's installed, it will be from this account.

Checked for and installed Java

The command to check for java is easy: # java - version.

The output showed we didn't have it installed, so it's time to get Java installed. (It's needed for Minecraft)

You can see from above Java wasn't installed. Installation was next using the command
sudo apt install default-jre

I also updated Java to the latest version and it's now openjdk version "16.0.1". :)

Now that Java is installed it's time to get Minecraft.

Downloading and installing the latest minecraft version.

I went to minecraft.net and downloaded the latest server.jar file. (Now it's obvious why I spent time getting Java set up.)

I renamed it from server.jar to minecraft_server.1.17.jar and placed it in it's own folder, /minecraft.

There's no real 'install' per se since it's a Java application. You just need to execute the .jar file to start the jvm.

Automating the startup

Since I know I want the Minecraft server to start when I start my Linux host, I created a start.sh script in bash and saved it in the /minecraft folder.

#!/bin/sh
while true
do
java -Xmx2048M -Xms2048M -jar minecraft_server.1.17.jar nogui
echo "restarting in 10"
sleep 10
done

This means that from now on, I can run the script to get the server running, and include all of my Java config I want to pass in when I start the Java process.

Next I made it executable via chmod +x start.sh,

I now have a startup script every time I want to launch this server. :)

Some Minecraft basics with a new server

The first time you execute the Minecraft .jar, the process outputs a eula.txt file. The process stops and you need to open and edit the file and set the eula=true in the file itself. Otherwise Minecraft won't start.

Pretty simple way to have a EULA agreement on a server than runs on command line IMO.

Use screen to launch the server and detach from it.

Linux has some great tools, and one of them is the screen command, which allows you to run commands in a terminal 'screen' then detach that screen from your current terminal window yet still continue running.

That means I won't have to worry about minecraft output from the start.sh script spewing all over my existing terminal.

After exectuting the script with ./start.sh, I was up and running!

OpenSSH to the rescue

After getting Minecraft running, now I need to get this server closed up, on my shelving, and configure ssh (secure shell) so that I can login to this server on the local network and manage it as needed without having an extra keyboard, mouse, and monitor.

The process for this is straightforward:

$ sudo apt install openssh-server

and to check the install:

$ systemctl status sshd (That's the output in the screenshot above)

Now, I just punch a hole in the firewall to allow ssh traffic into my server:

$ sudo ufw allow ssh

Since I want this to start every time the machine boots, I can enable that with:
$ sudo systemctl enable ssh

After doing some basic config, I'm now able to:

• login remotely with the minecraft user on the local network,
• detach the running minecraft process from the terminal,
• start, stop, restart the server easily.

Testing our server :)

After starting up minecraft, I launched my Minecraft Client to connect to our new server.

Wham! There it is:

Couple of odds 'n ends

After I have the minecraft server installed and up and running, it was time for some tweaking.

• I reduced mem consumption down to 1024M from 2048 for the jvm since this box only has 4Gb mem total.

• Changed Runlevel from 5 to 3. - Since a GUI is no longer needed on the server, I set the runlevel to 3 via: ln -sf /lib/systemd/system/runlevel3.target /etc/systemd/system/default.target Now when it boots, none of the gui processes will start, and I'll get better system resource utilization since I only need command line.

• Cranked down some user permissions and firewall rules.

I won't document these steps for now, but I did chmod a few files, set some of my ufw firewall rules, and set up some additional cron job to run a script that cleans up some logging daily, so that the server stays nice and optimized.

Onward and Upward!

Now that I have this machine hooked up, there's a lot more that I added to my To Do list. :)

I really enjoyed setting this up with Kai, (that's a photo of the both of us from last night) and he asked a lot of questions along the way.

Hopefully I can teach him to be a good admin and follow some simple practices to make his life easier with IT.

The best part of all this is now I will have a server I can use for my php\MySQL training I am working on, and a place for me to have fun playing Minecraft with my son on our own persistent LAN world. :)

Some useful links

If you're interested in setting up your own server, a little light reading is required, but it's nothing overwhelming. Here's some of the docs I used in setting this up:

https://lubuntu.me/downloads/
https://rufus.ie/
https://www.cyberciti.biz/faq/upgrade-update-ubuntu-using-terminal/
https://www.digitalocean.com/community/tutorials/how-to-install-java-with-apt-on-ubuntu-18-04
https://www.binarytides.com/linux-command-check-memory-usage/
https://linuxconfig.org/ubuntu-20-04-ssh-server
https://www.openssh.com/
https://likegeeks.com/linux-runlevels/
https://opensource.com/article/19/10/linux-server-security
https://askubuntu.com/questions/225471/how-to-install-minecraft-server
https://www.vultr.com/docs/how-to-install-a-minecraft-server-on-ubuntu-20-04

Final Thoughts

If I could give any piece of advice, it would be:

NEVER run any of the commands above without first reading the docs and man pages for a command and fully understand what you are doing.

Otherwise you can do harm to a server by running commands that are destructive. In my case, this is a test server that I don't use for anything permanent.

I enjoyed this process especially since Kai helped me every step of the way, and will make more of these posts whenever I need to do server maintenance or security updates. :)

Peace and love,

-Rob

P.S. Since I am trying to get back into doing regular posts, I also wanted to say that I am #alive, and part of the #aliveandthriving crew :)

Edited to add: After reading today's AliveChat, I am tagging this with #aliveandthriving. Nice job @flaxz and Alive tribe!