Hello,
According to the official eXist-DB documentation, the minimum system requirements are:
- At least Java version 8 (since eXist-db 3.0)
- About 200Mb of disk space for the installation
- At least 512Mb memory to run
This means that you could start with the smallest Droplet at $5 per month and then upgrade if you ever need to.
Regarding the installation, first you would have to install Java, you can follow the steps on how to do that here:
https://www.digitalocean.com/community/tutorials/how-to-install-java-with-apt-on-ubuntu-18-04
After that I would suggest following the steps from the official eXist-db
documentation :
Download the installer by following the download link on the eXist-db homepage page. We recommend that you download the latest stable release. The installer is a single file called eXist-db-setup-[version].jar (for instance eXist-db-setup-3.6.1.jar).
Upload the installer to your droplet
Then launch the installer:
java -jar eXist-db-setup-[version].jar
- You would get an installation command-line interface that you could go through to finish the setup. At the end you should get something like
[ Console installation done ]
Then if you’ve selected the default installation directory you could start the service up with the following:
/usr/local/eXist-db/bin/startup.sh -u admin -p password
Then by default the application would start on port 8080 and port 8443, so if you visit your droplet’s IP followed by the 8080 port you should see the application.
Hope that this helps!
Regards,
Bobby

by Koen Vlaswinkel
In this guide, you will install various versions of the Java Runtime Environment (JRE) and the Java Developer Kit (JDK) using `apt` . You'll install OpenJDK as well as official packages from Oracle. You'll then select the version you wish to use for your projects. When you're finished, you'll be able to use the JDK to develop software or use the Java Runtime to run software.