Today I logged into my Multicraft server to do a little routine maintenance, software updates.
Once I ran the necessary commands and updated software I noticed that my Minecraft server would not start, spitting out the error below.
Unsupported Java detected (55.0). This version of Minecraft requires at least Java 16. Check your Java version with the command 'java -version'.
That’s odd, because I was running the latest stable version for my distribution, after searching across message boards I discovered that for whatever reason the bleeding edge version of Java is too new for Minecraft to run.
To rectify the issue you need to migrate back to an older version of Java, the easiest way is to add the repository below and install a version of Java that actually works.
First you need to remove Java from your machine by running this command.
sudo apt remove default-jdk default-jre
Best to also purge the remaining files just to ensure there’s no conflicting files remaining.
sudo apt purge default-jdk default-jre
Now to install a compatible version of Java that works, or at least for my machine.
Linux Uprising maintain a reputable repository of Java versions, this is the repository we’ll be using. https://launchpad.net/~linuxuprising/+archive/ubuntu/java
sudo add-apt-repository ppa:linuxuprising/java
Now to install a working version of Java.
sudo apt-get install openjdk-16-jre
And that’s it, your Minecraft server should now start again. I imagine the newer version will get fixed as this issue seems to be very widespread, so this should only be a temporary fix.