Tech Vault

Server operating systems

The operating system decides how you install apps and how much you learn along the way. Pick one, stick with it for a month, and switch later if it annoys you.

Checked 9 November 2026

Our pick

ZimaOS

A free system made for home servers that never asks you to type a command. It installs from a USB stick, and from then on everything happens in a web page: install Jellyfin, Immich or AdGuard Home from its App Store with a click, browse and share files in its Files app, and combine drives into a RAID from its settings. Apps run in Docker underneath, so one that isn't in the store can still be added by pasting its Compose file.

Follow the guide, 45 minuteszimaspace.com
Cost
Free, paid licence optional
Good for
A first server on an old laptop, desktop or mini PC, for anyone who wants apps running this evening without learning the terminal first.
Watch out for
It runs only on normal 64-bit Intel or AMD computers, not on a Raspberry Pi. The free plan covers 4 disks and 3 member accounts, and a one-off paid licence lifts both. You learn less about what happens underneath, and fewer guides online are written for it than for Ubuntu.

What a server operating system is

Every computer runs an operating system: Windows, macOS or one of the many kinds of Linux. A server operating system is one made for a computer that nobody sits at. It leaves out the desktop, runs its apps without anyone logged in, and expects to be managed from another device, either through a web page or by typing commands over the network.

The system you choose mostly changes how you install and look after apps. Underneath, nearly all the options on this page run apps the same way, in containers with Docker (the Docker and containers page explains what that means). So the apps are the same wherever you start, and what you learn carries over if you switch.

Web page or terminal: decide this first

This one choice shapes everything else.

  • Never open a terminal, with ZimaOS. It installs from a USB stick, and from then on you do everything in a web page with an App Store. You learn less about what happens underneath, and you rely on its store for most apps, although it can also import any app that publishes a Docker Compose file.
  • Learn the terminal, with Ubuntu Server and Docker. You install and update apps by typing short commands from your laptop. The first evening is slower, but almost every guide online assumes this setup, and when something breaks you’ll understand why. Each long-term release gets five years of free security updates (the current one is 26.04 LTS, from April 2026), and it installs security fixes on its own every day.

Neither is the wrong answer. If the terminal is what’s stopping you from starting at all, start with ZimaOS. You can move to Ubuntu later, and the Linux command line page is there for when you get curious.

Which one suits you

System How you add apps Terminal needed Cost
ZimaOS App Store, or paste a Compose file No Free up to 4 disks and 3 users
Ubuntu Server Typed commands and Compose files Yes Free
Proxmox VE Inside virtual machines you create For some jobs Free
TrueNAS Its apps catalogue Rarely Free
Unraid Community Apps, in its web page Rarely Paid licence
Raspberry Pi OS Lite Typed commands, like Ubuntu Yes Free

ZimaOS, TrueNAS and Unraid need a normal Intel or AMD computer. On a Raspberry Pi, use Raspberry Pi OS Lite or Ubuntu Server’s Pi version.

What it needs

  • A spare 64-bit Intel or AMD computer whose disk you can wipe. ZimaOS asks for 4 GB of memory (8 GB recommended) and at least 25 GB of storage. It must be able to start in UEFI mode with Secure Boot turned off, which almost every PC from the last decade can.
  • A USB stick of 4 GB or more that you can wipe.
  • Another computer to make the stick and to manage the server afterwards.
  • A network cable from the server to your router.
  • About 45 minutes, much of it waiting.

How ZimaOS fits in

  • An App Store. Search for an app, press install, and its icon appears on the dashboard. Jellyfin, Immich, AdGuard Home, Home Assistant, Crafty for Minecraft and many more are there.
  • Apps from anywhere else. For an app that isn’t in the store, press + on the dashboard, choose Install a customized app, then Import, and paste the Compose file from the project’s instructions.
  • A Files app. Browse and manage everything on the server from your browser, make a share link for a folder, and connect Google Drive, Dropbox or OneDrive. Your storage is also shared on your home network, so it shows up in File Explorer on Windows and Finder on a Mac.
  • Drives from a web page. Combine drives into a mirror or another RAID layout under Settings, then Storage. The storage and drives page explains which to choose.
  • Accounts for the family. Each person gets their own login, and you choose which folders they can see.
  • Backups and power cuts. Phone and computer backup are built in, and a UPS connected by USB can shut the server down safely when its battery runs low.
  • Apps for your devices. ZimaClient, for Windows, macOS, iPhone and Android, finds the server on your network and can reach it when you’re away from home.

The easy way to set it up

ZimaOS needs nothing typed at any point. The step-by-step guide covers every screen, and the outline is:

  1. Make the USB stick. On your everyday computer, download ZimaOS USB Creator from the ZimaOS website, choose ZimaOS and your stick, leave Exclude system drives ticked, and press Write. If USB Creator won’t run, balenaEtcher does the same job with the file ending in _installer.img from ZimaOS’s releases page on GitHub.
  2. Change two BIOS settings on the spare computer: turn UEFI boot on and Secure Boot off.
  3. Install. Start from the USB stick using the boot menu key (often F12, F11 or Esc), choose the disk, and confirm. That disk is erased.
  4. Open the dashboard. Restart without the stick. The screen shows an address; type it into a browser on another device and create your account.
  5. Add apps. Open the App Store, search, and install.

Then ask your router to keep giving the server the same address. Look for DHCP reservation in its settings; the networking basics page explains why it matters.

Already running Ubuntu, Debian or Raspberry Pi OS? CasaOS, from the same company, adds a similar app store on top. It does need one pasted command, curl -fsSL https://get.casaos.io | sudo bash, and its last full release was in December 2024, so treat it as a convenience rather than something to build on for years.

The terminal route, with Ubuntu Server. Download Ubuntu Server LTS, write it to a USB stick with balenaEtcher, and follow the installer’s menus, ticking the box to install the OpenSSH server so you can log in from another computer. Then install Docker by following Docker’s own instructions at docs.docker.com, not the Docker option in the installer’s list of extras.

Questions people ask

Does ZimaOS cost money?

Not for most homes. The free plan allows 4 disks and 3 member accounts. A one-off licence, not a subscription, removes those limits if you outgrow them.

Can I switch later?

Yes. Switching means reinstalling, which wipes the system disk, so back up your apps’ data first (see backups). Because the apps run in Docker on almost every option here, the same apps are waiting on the other side.

Do I need a screen and keyboard?

Only to install it. After that the server runs without them, and you manage it from another device. Keep them nearby for the day something won’t start.

Should I start with Proxmox?

Only if you already know you want several separate systems on one machine, such as Home Assistant OS beside your apps. It adds a layer to learn first. The virtual machines page explains when it’s worth it.

What if storage is the main job?

For a box full of hard drives, TrueNAS and Unraid are built around storage and are managed from a web page. ZimaOS can also combine drives into a RAID from its settings, within the free plan’s 4 disks.

Also good

Skip

Next