Some of the HP DeskMini machines might be a good one. There’s a model that has 2 x m.2 for a little high speed network storage or as a HTPC.

https://jellyfin.org/docs/general/quick-start/ Here’s a quick start for Jellyfin, depending on which OS you wish to install, there’s also one line scripts that can set it up in LXCs (linux containers) that share the linux kernel with the host operating system, such as Proxmox… https://community-scripts.github.io/ProxmoxVE/ (always make sure before setting up you read before executing and understand what the script is about to do, just to reiterate safety) As far as *arrs, https://wiki.servarr.com/ here are some setup guides for the most common. Podman and Docker are the most common container software, depends on what you need from both of em, podman is by default rootless, while docker is set up as privileged by default, while you need to execute a small command to get it to run rootless, which is in their docs respectively.

Something to remember: NAS is just an acronym for Network Attached Storage. A NAS is not a specific product.

You can run NAS software on pretty much anything. My current NAS is a Mac Mini 2014 with a 4-bay USB drive enclosure. I’m in the process of building a more reliable NAS out of an old HP ProLiant ML110 G2 case - which is fully ATX compatible, strangely enough - with modern(ish) guts. It’s got 10 drive bays, too.

While any machine that provides storage through the network can be a NAS, you’ll probably want at least some level of extendability. Your biggest problem with OEM machines (think Dell, HP, Lenovo) will be s lack of SATA ports, in combination with not enough power outlets and not enough space to put the actual disks in the case.

That’s the reason I usually build my own machines for those purposes, and depending on what’s needed you don’t even need high-end parts, at least for a “NAS-only NAS”. My NAS works on a 2 core/ 4 thread Intel i3, which will be enough for the foreseeable future. But it also only provides storage, all the rest (self hosting my services) happens on another machine.

TrueNAS works well for me as a NAS OS. AS far as I’ve seen it also provides direct container support or virtual machines. It you want an all-in-one machine, that might be worth looking into.

lookup Open Media Vault

If you can boot an os from usb (basically the same for all distros) you can try proxmox.

There are these incredibly useful helper scripts that setup entire services in 1-2 copy pasted commands.

https://community-scripts.github.io/ProxmoxVE/

To explain what proxmox is its basicly virtualisation software, it can run vms but also lxc (light linux containers) and share resources very efficiently between all of them

Jellyfin, radarr, sonar. They are all included in the helper scripts, each will be a dedicated lxc.

Its also very easy to setup raid and there own storage format is very efficient.

Its well documented to the point that any decent llm can help you learn whatever you need. In fact its claude that helped me setup my own proper raid on proxmox, also tought me about datasets and how i can make those available to different lxc

Personally i am very hands off with my server, the hardest part is often choosing what ip i want to give a service, i rarely update or mess with it if not strictly necessary.

For hardware i recommend plenty of ram (can Be bought and installed seperatly), more cores is usually better and internal graphics can save you some hassle depending on what you are doing (also allows you to dedicate a Big gpu to some services).

A warning on second hand corporate machines, the performance is often good But quite fans are often an afterthought. I onxe got a beast of machine for free but you could hear it spin from anywhere in my house.

A good practical case is always a blessing when you need to check the insides.