RackBrief

Home server software, side by side

These are the systems people install on a machine at home. They are not competing for the same job, which is the first thing most comparisons get wrong.

Two of them run other computers inside themselves, so one physical box can behave like several. Others exist to look after disks: keeping files safe, noticing when a drive is failing, and sharing folders across the house. Picking between them starts with which of those two things you actually want, and the honest answer is often both, which is why running one inside the other is so common.

Checked against each maker's own documentation on 21 September 2026. Where a maker does not publish a figure, the table says so rather than guessing.

Stated requirements are the maker's own minimums for the current release, which are what it takes to boot, not what it takes to be useful. Treat them as a floor.
SystemWhat it is forFreeLicenceBuilt onCurrent releaseMemoryDisk
Proxmox VERuns other computers inside itselfYesAGPL-3.0-or-laterDebian 139.21 GBnot stated
UnraidBothPaidProprietarynot stated7.3.2not statednot stated
OpenMediaVaultLooks after disks and filesYesGPL-3.0Debian 138.5.81 GBnot stated
TrueNASLooks after disks and filesYesLGPL-3.0Debian Linux25.10.78 GB20 GB
CasaOSmaker points elsewhereRuns apps, simplyYesApache-2.0not statedv0.4.15not statednot stated

What each one is, in one line

Proxmox VE
A free, Debian-based platform for running virtual machines and containers on your own hardware. The software is free to download and use; Proxmox sells optional paid subscription plans (support + access to the more-tested enterprise package repository).
Unraid
A Linux-based OS that turns a PC into flexible network storage plus a Docker and VM host. Free for a 30-day trial (no credit card required); perpetual licenses are one-time purchases: Starter $49 (6 storage devices, 1 year of updates), Unleashed $109 (unlimited devices, 1 year of updates), Lifetime $249 (unlimited devices, lifetime updates).
OpenMediaVault
A free Debian-based NAS operating system with a web interface for storage and file sharing. Fully free and open source; no paid tier.
TrueNAS
An open-core, ZFS-based operating system for building network-attached storage servers. TrueNAS Community Edition is free to download and run on your own hardware; TrueNAS Enterprise (turnkey appliances plus 24x7 support) is paid.
CasaOS
An open-source home-server dashboard that adds an app store and file manager on top of Linux. Free and open source. Its vendor-promoted successor, ZimaOS, has its own separate pricing/tiers not covered by this record.

Which one, then

If the machine's job is to hold files and you want the least to go wrong, start with a storage system. If you want to run several things that do not get on with each other, or you want to be able to undo a mistake by rolling a whole machine back to yesterday, start with a system that runs virtual machines. If you cannot decide, the common answer in practice is to install the virtualisation system on the metal and run the storage system inside it, which gives you both at the cost of one more layer to understand.

The one thing worth settling before you install anything is what happens to your data when a disk dies, because that is the decision that is expensive to change later.

A figure here is only true of the release named in its row. When a maker ships a new version we re-check these pages and re-date them. If something is wrong, please tell us.