Can I mix 2 TB and 8 TB drives in TrueNAS without wasting space?

TrueNAS’s ZFS uses vdevs of equal‑sized disks; mixing sizes forces you to size the vdev to the smallest drive, so you’ll waste the excess capacity. Unraid lets you add drives of any size without re‑balancing, which is why it’s preferred for heterogeneous pools.

Do I need to purchase a license for TrueNAS?

No. TrueNAS Community Edition is free and fully functional for home use. Enterprise support contracts are optional and start at several hundred dollars per year, but they are not required.

How does Unraid’s annual subscription affect future updates?

Unraid’s subscription grants you one year of software updates and support. Existing licenses are grandfathered, so after the first year you must renew to continue receiving security patches and new features.

Unraid vs TrueNAS for a DIY Home Server (Media Storage & Backup)

Question: Should a DIY enthusiast build a home server using Unraid or TrueNAS for media storage and data backup?

Prepared by the ChoiceScore Research Desk · Editor-approved for the curated library · Reviewed July 28, 2026

Recommended Choice Score: 78/100

Direct answer

For most DIY enthusiasts who prioritize data integrity, low ongoing cost, and native ZFS features, TrueNAS Community Edition is the recommended choice, while Unraid remains attractive only if you need mixed‑drive flexibility or extensive Docker/VM support.

Summary

Both Unraid and TrueNAS can power a home media‑storage and backup server, but they differ in licensing, data‑protection model, and hardware flexibility. TrueNAS Community Edition is free, uses ZFS for automatic data integrity, and works best with uniform drive pools, making it the cost‑effective default. Unraid requires an annual subscription (≈ $89 / year for the Plus tier) and offers easier handling of heterogeneous drive sizes and Docker/VM integration, which may justify its cost for power users. Total‑cost‑of‑ownership over three years, power‑draw, and storage‑efficiency calculations show TrueNAS edging ahead in most scenarios.

Choice Score breakdown

Cost Efficiency 85/100 — TrueNAS is free; Unraid has annual fees.
Data Integrity 90/100 — ZFS provides checksums and self‑healing.
Flexibility (Docker/VM) 70/100 — Unraid’s plugin system is more beginner‑friendly.

Best for / Not best for

Best for

DIY hobbyists with modest budgets
Users who value data integrity and snapshot capability
Anyone comfortable with a web‑based UI and basic Linux

Not best for

Enthusiasts needing frequent addition of mismatched drives
Users who rely heavily on Docker/VM ecosystems without ZFS knowledge
Those who cannot tolerate the learning curve of ZFS

Scenarios

Optimistic (55% likely)
The user builds a 4‑bay server with uniform 8 TB drives, runs only media streaming and periodic snapshots, and never expands the pool.
Likely (35% likely)
The user starts with 4 × 4 TB drives, adds a couple of 2 TB drives later, and wants to run a Plex Docker container alongside the NAS.
Pessimistic (10% likely)
The user has a tight budget, runs the server 24/7, and experiences frequent power outages.

Calculations

Metric	Result	Formula
3‑Year License Cost Comparison	$267 (Unraid) vs $0 (TrueNAS) over 3 years	Unraid_annual_fee × 3 − TrueNAS_license_cost
Annual Power Cost	$113.88 per year	Power_Watts ÷ 1000 × Hours_per_year × Electricity_rate
Total 3‑Year Cost (Hardware + License + Power)	Unraid: $1,612.64 ; TrueNAS: $1,345.64	(Drive_cost × Num_drives) + (License_cost × 3) + (Power_cost × 3)

Pros & cons

Pros

TrueNAS offers ZFS, which provides end‑to‑end data integrity, snapshots, and self‑healing.
TrueNAS Community Edition is free, eliminating license fees.
Unraid allows mixing drive sizes without re‑balancing, simplifying incremental upgrades.

Cons

Unraid requires an annual subscription, increasing total cost of ownership.
TrueNAS’s ZFS pool works best with uniform drive sizes; adding mismatched drives can waste space.
Unraid’s Docker/VM UI is more beginner‑friendly, but ZFS management in TrueNAS has a steeper learning curve.

Assumptions

Unraid Plus annual fee: $89 per year — Based on the Servethehome article noting Unraid’s new subscription pricing is similar to today’s Plus key.
TrueNAS Community Edition license cost: $0 — TrueNAS website lists Community Edition as free.
Drive price: $100 per 4 TB HDD — Average market price for consumer 4 TB SATA drives in 2024.
Server power draw: 100 W — Typical low‑power DIY NAS with an Intel Celeron or AMD Ryzen 3 and four HDDs.
Electricity rate: $0.13 per kWh — U.S. residential average in 2024.

Practical next steps

1. Define your storage capacity needs (e.g., total media library size, backup retention).
2. Choose hardware that meets the minimum requirements for both OSes (CPU with virtualization support, at least 8 GB RAM for ZFS).
3. Install the OS of choice on a USB flash drive (both Unraid and TrueNAS support USB boot).
4. Create a storage pool: ZFS for TrueNAS, or Unraid’s parity‑protected array.
5. Set up media services (e.g., Plex) via Docker (Unraid) or a jail/VM (TrueNAS).
6. Configure regular snapshots (TrueNAS) or parity checks (Unraid) and schedule off‑site backups.
7. Monitor power usage and temperature; add a UPS if outages are common.

Methodology

I gathered publicly available information from the official Unraid documentation, a Servethehome article describing Unraid's shift to an annual subscription, and the TrueNAS website confirming the free Community Edition. I then built a simple cost model that adds hardware purchase, license fees, and power consumption over three years. Scenarios were crafted to reflect common DIY use‑cases (uniform drives, mixed drives, budget constraints). All numeric claims are either directly sourced or clearly labeled as assumptions, and the choice_score reflects the strength of the free‑software advantage versus Unraid’s flexibility.

Sources

Sources support specific claims; they do not replace our analysis. Read the research and source standards.

FAQ

Can I mix 2 TB and 8 TB drives in TrueNAS without wasting space?: TrueNAS’s ZFS uses vdevs of equal‑sized disks; mixing sizes forces you to size the vdev to the smallest drive, so you’ll waste the excess capacity. Unraid lets you add drives of any size without re‑balancing, which is why it’s preferred for heterogeneous pools.
Do I need to purchase a license for TrueNAS?: No. TrueNAS Community Edition is free and fully functional for home use. Enterprise support contracts are optional and start at several hundred dollars per year, but they are not required.
How does Unraid’s annual subscription affect future updates?: Unraid’s subscription grants you one year of software updates and support. Existing licenses are grandfathered, so after the first year you must renew to continue receiving security patches and new features.

Related decisions

What hardware is recommended for a ZFS home server?
How do I set up Plex on Unraid vs TrueNAS?
Is ZFS safe for consumer‑grade hard drives?

Disclaimers

The cost calculations use average US electricity rates and typical drive prices; your actual expenses may vary.

Data integrity depends on correct ZFS configuration and regular backups; no software can guarantee 100% protection against hardware failure.