I’ve been thinking about using client-side certificates that are validated by Caddy to bypass the Authentik wall (proxy provider) I use. I’ll give it a shot some time, it’s a good idea

Other user summarized very well.

No I have accrued knowledge of those things over time, no one stop shop that I know of. But knowing these things exist and their general use are half the battle!

I was lazy with the “Authentik wall” because I couldn’t remember what they called it. It is the “proxy” option in their “provider” section https://docs.goauthentik.io/add-secure-apps/providers/proxy/ . There are many guides for Authentik at least, it’s complicated but you only need to do specific things for it to work - and most tell you and the rest are applicable via matching similar looking things.

OIDC is an open login protocol many things support. I think jellyfin can use it with a plugin, but keep in mind that regular user creation still exists so it’s not a security and convenience feature like for most things, it’s just a convenience feature.

DMZ is de militarized zone. I used the acronym to mean a gap between your system and a system that deals directly with the outside Internet. That gap is the VM separation. LXC containers and docker containers do not have that separation, I deploy Internet-facing stuff in a VM as extra insurance in case they get zero-day-hacked; it means the rest of my server will hopefully not get ransomwared.

Incus is an alternative to proxmox, but less needy since it doesn’t require its own Linux kernel. Zabbly is a package source (vs built-in Debian sources) that has the web ui in it. See their documentation for installation, it tells you how to add the Zabbly package; use the “stable” version if you do use incus.

“In the compose” means in the docker-compose.yml file.

‘Cap-drop: all’ is an entry you can make in the docker-compose file. It increases security. All of the ones I listed are entries you can add to the docker-compose file. You’ll likely need a

tmpfs: /tmp

In the compose file you use read only.

Podman is the superior alternative to docker, and Podman quadlets are a way to deploy containers (they have a couple ways, like docker does - you don’t need a docker-compose.yml file to run docker containers). But it’s new and doesn’t have the community knowledge support via searching like docker does.

Hope that helps!

Thanks for the links! I had no idea there were special settings needed

I am not familiar with deploying client side certificates unfortunately. I hope it works, if the certificate is at the OS level and the application will use it, I feel it will work… not sure, in-browser feels straight forward at least

Reading jellyfin’s issues it’s clear its web ui and API cannot be allowed to talk to the general internet.

I’d push for a VPN solution first. Tailscale or wireguard. If you’re happy with cloudflare sniffing all traffic and that they make take it away suddenly someday use their tunnel with authentication.

The only other novel solution I’d suggest is putting jellyfin behind an Authentik wall (not OIDC, though you can use OIDC for users after the wall). That puts security on Authentik, and that’s their only job so hopefully that works. I’d use that if VPN (tailscale or wireguard) are problematic for access. The downside is that jellyfin apps will not be able to connect, only web browsers that can log into the Authentik web ui wall.

Flow would go caddy/other reverse proxy -> Authentik wall for jellyfin -> jellyfin

I’d put everything in docker, I’d put caddy and Authentik in a VM for a DMZ (incus + Zabbly repo web ui to manage the VM), I’d set all 3 in the compose to read-only, user:####:####, cap-drop all, no new privileges, limited named networks.

Podman quadlets would be even better security than docker, but there’s less help for that (for now). Do docker and get something working to start, then grow from there

I’m looking at Opnsense on an Incus VM soon, what was your fight there? Good to know what I’ll hit ;)

Agreed on that path - some networking (like mimicking proxmox’s bridge connections which give VMs their own MAC/IP) takes effort to find the solution. But the basic LXC/VM-shares-your-IP works super easily and the script ability is great. Plus it doesn’t feel like a yoke on your system that is heavy and drives it, but just another application! I feel it’s close enough, and when you get it where you want it, it’s perf. I assume they’ll get “one click” solutions for the harder stuff baked in as they get more attention and traction.

If you’ve got Debian already installed, I cannot resist advocating for Incus (stable branch from Zabbly repo with web ui https://blog.simos.info/how-to-install-and-setup-the-incus-web-ui/) in lieu of proxmox. Does the same thing but you don’t have to rip out the kernel Debian uses.

With Debian 13 you have access to podman quadlets, use that for any non-vm needs. The ease of docker compose files easily removes reason for programs in LXC containers, and podman removes reason for docker in an LXC. LXC is left only for programs that aren’t containerized. VMs for security DMZ. Podman for bulk of stuff you want.

Good luck!

I see now that a limitation I just understood for IPv4 (expose one port from one device only on the router) isn’t a thing for IPv6 working without NAT, every device on a LAN can be given a world wide routable address and expose the same port. Interesting, in my home I don’t think I’d ever run into that, but I can see issues like that pile up quick in big deployments.

Thanks for taking the time to explain all of this in detail!

I gather people talk like NAT is a rung of hell, but I guess it works because I never think of it. Maybe it becomes shittastic at multiple NATs? With one router it seems straight forward to have port forwarding.

I do not understand why I want better inbound connections - but maybe if I get hit with a cgnat then I’ll understand?

I see people say “not worth it” but never expound on what exactly makes it not worth it?

Most I get is a vibe (using a metaphor) “python-like judging where people prefer to do it in a ‘pythonic’ way” but of course that’s silly. There must be more to it, but I never seen interoperability issues called out