I could have had an x86 server running with that much RAM

You only get that much memory with ARM. With x86 I think you only get 2 vcpus and 4GB of RAM. But for containers, if they run on ARM, it’s great. And Mailu has been running very smoothly so far.

As of downsides… well, it’s Oracle. But other than that, I actually find Oracle Cloud interface and offerings much more intuitive and straightforward than other big providers such as AWS or specially Azure, at least for non power users.

I recently moved all my personal accounts to a VPS instance. I decided on Mailu’s docker compose setup because of its ease of use and it has been working great so far.

I used Oracle’s free tier cloud (4 ARM vcpus and 24GB of memory) and email delivery instances so it’s worth a try, but any other cloud provider offer similar options.

Yes, it’d work just fine because each container listens on port 8000 of their own IP address, not the docker server’s IP address. Caddy/Traefik just redirects traffic to that port.