Part 1: Installing TrueNAS SCALE on bare metal
This is the first post in a series on building a home server with open-source software. We'll go from a blank machine to a working NAS, then layer on Nextcloud, Immich, and Navidrome in the posts that follow.
What is TrueNAS SCALE?
TrueNAS SCALE is a Linux-based NAS operating system built around OpenZFS — one of the most robust filesystems ever written. It gives you enterprise-grade storage features (snapshots, checksums, scrubbing, compression) in a free, open-source package.
The current stable release is 25.04 "Fangtooth", which replaced the old Kubernetes-based app system with straightforward Docker containers. That change made running apps considerably simpler, and it's what we'll be using throughout this series.
One important mindset shift: TrueNAS is an appliance OS, not a general-purpose Linux distro. You manage it entirely through the web UI. Don't install packages via apt, don't modify system files by hand — doing so will break things and block upgrades.
I had an existing TrueNAS Core system which I wanted to migrate to the SCALE version. In order to do this, the first step was to export the disks in TrueNAS Scale:
- Storage > Export / Disconnect and repeat for all the disks in the system
This will put the ZFS volumes in a safe state ready for importing to the new TrueNAS SCALE system.
Hardware:
Boot disks of 2 x 250GB 2.5" SSD SATA Main storage disks of 2 x 6TB Seagate ST6000VN006 Single 1TB 2.5" SSD for CCTV storage
AsRock Mini-ITX motherboard C2750D4I (8 core Intel Atom) 32GB ECC memory
Hardware requirements
TrueNAS is flexible, but it has firm minimums:
- CPU: Any x86_64 Intel or AMD processor — modern NAS boards, old workstations, and mini PCs all work
- RAM: 8 GB minimum; 16 GB is comfortable; ECC RAM is preferred but not required for home use
- Boot device: 20 GB minimum — an SSD or NVMe stick is ideal; TrueNAS recommends against USB sticks as a boot device
- Storage drives: Separate from the boot device; these hold your actual data
Your data drives are completely separate from the OS drive. TrueNAS lives on the boot device alone, and the drives you add to a storage pool are never touched during OS installs or updates.
Step 1: Download the ISO and write it to USB
Go to truenas.com/download and grab the latest SCALE ISO. At the time of writing, that's 25.04.
You need a temporary USB stick (8 GB is enough) to boot the installer. Write the ISO to it using Balena Etcher (Windows/macOS/Linux) or Rufus (Windows). Both are free and handle this in a few clicks.
Why a temporary USB? The installer runs from this stick, then installs TrueNAS to your actual boot device. Once installed, you no longer need the USB.
Step 2: Boot into the installer
Plug the USB into your machine and boot from it. You'll need to either change the boot order in BIOS or hit the boot device selection key during POST (usually F8, F11, or F12 depending on your board).
Once the installer loads, you'll see a text-based menu.
Step 3: Walk through the installer
Select Install/Upgrade from the menu.
You'll be shown a list of detected drives. Select your boot device — the SSD or NVMe where TrueNAS will be installed. This is not where your data will live. Double-check you're selecting the right drive; the installer will erase it.
If prompted about swap, choose No swap. TrueNAS manages memory differently from a standard Linux system, and a swap partition on the boot drive isn't needed or recommended.
Select option 1: Administrative user (admin) and set a strong password. This is the account you'll use to log into the web interface.
The installer will write TrueNAS to the boot device. When it finishes, shut down, remove the USB stick, and boot from the newly installed drive.
Step 4: Find the web UI
TrueNAS doesn't have a traditional desktop — it's headless by design. After booting, the console will display a local IP address, something like:
Web UI: http://192.168.1.100Open that address in a browser on another machine on your network. Log in with the admin account and the password you set.
If you don't see an IP, your machine may not have picked up a DHCP address. Connect a monitor and keyboard temporarily; the console menu lets you set a static IP manually.
Step 5: Initial configuration
A setup wizard will walk you through the basics. The most important decisions here are:
Storage pool creation. This is where you tell TrueNAS which drives to use for data. A pool is a ZFS construct that wraps one or more drives. Common layouts for home use:
- Single drive: Fine for getting started; no redundancy
- Mirror (RAID-1 equivalent): Two drives, one is a mirror; survives one drive failure
- RAIDZ1: Three or more drives; one drive can fail safely
- RAIDZ2: Four or more drives; two drives can fail safely
ZFS is not a backup. Even with RAIDZ2, a pool protects against drive failure — not against accidental deletion, ransomware, or catastrophic hardware failure. Plan your backups separately.
Timezone and NTP. Set these correctly. Snapshots and scheduled tasks depend on accurate time.
Step 6: Set up the Apps pool
Before installing any apps, you need to tell TrueNAS which pool to use for application storage. Go to Apps in the left sidebar, then follow the prompt to choose a pool.
TrueNAS will create a dedicated dataset on that pool for Docker container data. This keeps app storage organised and separate from your personal data.
What you have now
At this point, you have a running TrueNAS SCALE system with:
- A ZFS storage pool for your data
- A web UI you can reach from any device on your network
- The Apps system ready to install software
In the next post, we'll install Nextcloud — your private Google Drive replacement — directly from the TrueNAS app catalog.