As described recently, we are now using Minetest at school. To make the operation secure on the one hand, and stable and reasonably efficient on the other, we have opted for a (partially) automated solution. At Hetzner-Cloud, where we get cheap servers, the machine runs in a CX41 configuration. Data backup takes place in the Open Telekom Cloud, because there is inexpensive mass storage there for archiving purposes.
The installation itself is mostly automated, only the last 10% has to be done manually - mainly managing the keys and starting the configuration playbooks. You can find the project on Github.