Unraid

Unraid is a paid, closed-source operating system for network storage, Docker apps, and virtual machines, sold by Lime Technology as a one-time license instead of a subscription. Its parity-protected array mixes drives of any size or brand in one pool, something ZFS-based systems like TrueNAS don’t allow.

What Unraid actually is

Unraid turns one machine into network storage, a Docker host, and a KVM virtualization platform, all from one web dashboard. The idea dates to 2005, when Lime Technology’s founder wanted to back up a growing DVD collection without buying matched drives for a traditional RAID array. The array does roughly the opposite of RAID: drives of any size, brand, or age sit side by side, protected by one or two parity drives instead of striped data. Add a bigger drive later and the array simply grows.

Not open source: how the Unraid license actually works

This is what separates Unraid from everything else here: TrueNAS, Proxmox VE, and OpenMediaVault are free and open-source, and Unraid is neither. Lime Technology sells three perpetual license tiers, priced on the official pricing page as of mid-2026.

Tier	Price	Storage devices	Updates included
Starter	$49 one-time	6 devices	1 year
Unleashed	$109 one-time	Unlimited devices	1 year
Lifetime	$249 one-time	Unlimited devices	Lifetime

Every tier unlocks the same feature set: the full array, Docker, VMs, and Community Applications. The only differences are storage device limits and how long free updates last before renewal.

Storage architecture: the array, parity, and cache pools

Unraid’s array is deliberately not RAID: each disk keeps its files whole instead of striping data across the group, so a data drive can usually be read on any Linux box outside Unraid, encryption aside. One or two dedicated parity drives protect the rest, and per Unraid’s own array documentation, data disks can’t exceed the parity drive’s size, so the single biggest drive should go to parity first; with dual parity, both drives must be at least as large as the biggest data disk, though they can differ from each other.

An optional cache pool, usually SSD or NVMe, sits alongside the array in BTRFS or ZFS with its own RAID levels, speeding up writes before a scheduled Mover process copies them onto the array overnight. That’s the real contrast with TrueNAS: its ZFS pools are built from mirrors or RAID-Z vdevs that want matched drives, striped for performance and mostly fixed once built, while Unraid trades some of that raw throughput and self-healing for growing one mismatched drive at a time, no pool layout required upfront.

Installing Unraid

1. Start the 30-day trial or buy a license, download the Unraid Server zip from the account portal, and write it to a USB drive with the official USB Creator tool.
2. Boot the target machine from that USB drive. Unraid runs entirely from RAM, and the drive stays inserted as both the boot device and the license key holder.
3. Open the assigned IP address in a browser, assign at least one parity drive plus your data drives, and start the array.
4. Install the Community Applications plugin from the Apps tab, then add Docker containers, a cache pool, or virtual machines as needed.

Docker apps and virtual machines

Docker support is what put Unraid on so many homelab shortlists. Community Applications, a plugin Lime Technology doesn’t build but ships with nearly every install, adds an app-store tab with 2,000+ free container templates and plugins, per Unraid’s own Community Applications documentation, though individual apps aren’t directly supported by Lime Technology itself. Virtual machines run on KVM through the same interface, GPU and USB passthrough included, for a gaming VM or Windows box sharing hardware with the NAS, none of it needing a terminal, the main reason Unraid has a reputation as the easier option next to Proxmox VE or TrueNAS.

Homelab use cases

The single most common reason people buy Unraid is upcycling: three or four old drives of different sizes pulled from retired PCs, combined into one array instead of thrown out, with qBittorrent, a media server, and a retro-gaming container among the common first Community Applications installs. Our own 4K Media Server Powerhouse build calls out this exact decision on the same Intel Quick Sync hardware: Unraid for mismatched-drive flexibility, or TrueNAS SCALE for ZFS’s data integrity, with the same Docker stack running on either.

Unraid vs. TrueNAS vs. OpenMediaVault vs. Proxmox VE

Homelabbers comparing Unraid usually have three other names on the list: TrueNAS, free and ZFS-based; OpenMediaVault, free and lighter-weight; and Proxmox VE, a hypervisor-first alternative for anyone who’d rather not run proprietary software on their NAS at all.

Category	Unraid	TrueNAS	OpenMediaVault	Proxmox VE
Cost	Paid, tiered by device count: $49–$249 one-time	Free, LGPL-3.0 core	Free, GPL-3.0	Free, AGPLv3
Storage	Parity array, mismatched drives, optional BTRFS/ZFS cache	ZFS-first: RAID-Z, mirrors, checksums	mdadm/LVM by default, ZFS via plugin	ZFS, Ceph, LVM, hardware RAID
Apps	Docker via Community Applications (2,000+ templates), plus KVM VMs	Docker Compose apps plus KVM VMs	Docker via plugin, lighter feature set	Native LXC alongside VMs; Docker runs in a VM
Best fit	Mismatched drives, beginners wanting Docker and VMs with minimal command line	Data integrity, open hardware choice	Simpler, lighter NAS needs	VMs and containers together, not primarily a NAS

Unraid: pros and cons

• Genuinely easy to run for a first NAS: a wizard-driven install and one of the largest homelab Docker catalogs available
• Mixes any drive size or brand in one array, and grows it one disk at a time without a rebuild
• KVM virtual machines and Docker containers side by side, GPU passthrough included, no command line required for either
• A genuinely perpetual license: pay once and keep that version running forever, even without renewing updates

• Not open-source and not free: licensing cost is real even at the $49 entry tier, and all sales are final
• Community Applications isn’t directly supported by Lime Technology, so quality and maintenance vary by author
• Array reads and writes run at single-disk speed rather than combined throughput, unless data sits in the cache pool
• The license is tied to a USB flash drive on versions before 7.3, one more piece of hardware to track and back up

FAQ

Is Unraid free?

No. Perpetual licenses start at $49 for six storage devices and reach $249 for a lifetime, unlimited-device key. The 30-day trial covers testing before any purchase.

Is Unraid open source?

No. The Linux kernel and Slackware base are open-source, but the array layer and web interface that make Unraid what it is are closed-source, owned by Lime Technology, unlike TrueNAS, OpenMediaVault, and Proxmox VE.

Unraid vs. TrueNAS: which one should I actually buy?

If your drives don’t match and a ZFS pool layout sounds like a chore, Unraid’s array is more forgiving. If the data itself needs protecting, TrueNAS’s ZFS checksums and self-healing make the stronger case, and it costs nothing. Plenty of homelabs run both, on different machines.

Unraid earns its Medium difficulty label from the license, not the interface: buying a key and backing up the USB boot drive are steps TrueNAS and Proxmox VE skip entirely. Past that, Community Applications and the array wizard are about as approachable as homelab software gets. If mismatched hardware and beginner-friendly Docker apps matter more than staying open-source, Unraid earns its price tag; our homelab setup guide for beginners covers the hardware decisions that lead here.