Selfhosted

We expose about a dozen services to the open web. Haven't bothered with something like Authentik yet, just strong passwords.

We use a solid OPNSense Firewall config with rather fine-grained permissions to allow/forbid traffic to the respective VMs, between the VMs, between VMs and the NAS, and so on.

We also have a wireguard tunnel to home for all the services that don't need to be available on the internet publicly. That one also allows access to the management interface of the firewall.

In OPNSense, you get quite good logging capabilities, should you suspect someone is trying to gain access, you'll be able to read it from there.

I am also considering setting up Prometheus and Grafana for all our services, which could point out some anomalies, though that would not be the main usecase.

Lastly, I also have a server at a hoster for some stuff that is not practical to host at home. The hoster provided a very rudimentary firewall, so I'm using that to only open necessary ports, and then Fail2Ban to insta-ban IPs for a week on the first offense. Have also set it up so they get banned on Cloudflare's side, so before another malicious request ever reaches me.

Have not had any issues, ever.

So there is https://en.wikipedia.org/wiki/Fail2ban which helps already to some degree.

But what are you trying to prevent? You have your services in a docker container, hopefully not running as root, which already makes it difficult to break out even if through a bug someone would be able to get access to the docker container.

I mean its not like your stuff is very important for someone to break in like the pentagon, you probably just have some photos from your phone on it, some lights can be switched on and off and some temperatures read.

I'm not trying to say that you should not care about it but I'm trying to figure out what your threat model is.

I've half ass thought about this but never have tried to actually self host. If you have access to all devices, why not just use your own self signed certificates to encrypt everything and require the certificate for all connections? Then there is never a way to log in or connect right? The only reason for any authentication is to make it possible to use any connection to dial into your server. So is that a bug or a feature. Maybe I'm missing something fundamental in this abstract concept that someone will tell me?

Why? Not every service is meant to be exposed to the open internet. Immich is the only one of what you listed that makes sense to have out in the open.