OpenMediaVault is the only one of the big three self-hosted NAS operating systems that officially supports the Raspberry Pi. TrueNAS and Unraid both require x86-64 hardware. OMV ships dedicated ARM images, and on the Pi specifically, those images come with the omv-extras plugin repository already installed, something you’d otherwise have to add by hand. That combination, a real NAS web interface plus genuine Pi support, is why a lot of homelabs start here instead of buying dedicated hardware. The OpenMediaVault comparison covers the licensing and how it stacks up against TrueNAS and Unraid; this is the actual walkthrough, from flashing the image to the USB storage quirks that only show up once you’re running it.
What you’ll need
- A Raspberry Pi 4 or 5, ideally with 4GB of RAM or more once Docker containers get added on top of file sharing
- A proper power supply, not whatever USB charger was already in a drawer. The Pi 4 undervolts easily on weak chargers, and OMV won’t handle random brownout reboots any better than any other NAS software would
- A USB SSD or hard drive enclosure for the actual storage. A powered enclosure or hub matters more than it sounds like it should, since a single Pi USB port often can’t reliably feed a spinning hard drive on its own
- A second USB drive or a fast microSD card to boot from, separate from the storage drives
- An Ethernet cable. Wi-Fi works, but the Pi’s Gigabit port is the more reliable choice for anything you’re calling a NAS
Flashing the image and first boot
- Download the Raspberry Pi build for your model from OpenMediaVault’s downloads page, not the generic x86 ISO. It’s a different image, and it’s the one with omv-extras already installed.
- Flash it to your boot drive with Raspberry Pi Imager or balenaEtcher.
- For a headless setup, drop an empty file named ssh into the boot partition before the first boot, and add Wi-Fi credentials to wpa_supplicant.conf if you’re not using Ethernet.
- Connect the storage drives and Ethernet, then power on. The first boot takes a couple of minutes while OMV resizes the filesystem and generates new SSH keys, longer than a normal reboot.
Logging in for the first time
Find the Pi’s address from your router’s DHCP client list, or scan for it with a tool like Fing or arp-scan; Pi images don’t always show useful output over HDMI by the time OMV is ready. The web interface’s default login is admin / openmediavault, and SSH defaults to root / openmediavault. Change both immediately, before doing anything else, then set a static IP or a DHCP reservation on the router so the address doesn’t shift later.
Storage: why RAID over USB needs a caveat
mdadm RAID works the same on a Pi as it does on any other OMV install, but the storage is USB-attached, and USB tolerates a drive dropping off the bus far worse than SATA does. A cheap cable or an unpowered hub can make a healthy drive look like a failed RAID member, which then kicks off a resync that hammers the same USB bus that just caused the problem. For a Pi NAS, a single disk with a real backup somewhere else, or a mirrored RAID1 on a powered hub with decent cables, is the realistic choice. Leave RAID 5 or 6 for actual SATA hardware.
Formatting and sharing is standard OMV from here: wipe and format the drive under Storage, File Systems, create a shared folder pointing at it, enable the SMB/CIFS service, and add the share under Services, SMB, Shares. Same steps as any other OMV install; the Pi doesn’t change this part.
Docker through omv-extras
Since the Pi image already has omv-extras enabled, installing openmediavault-compose is a couple of clicks under System, Plugins, instead of the manual repository setup the x86 install needs. Worth being honest about limits here: a Pi handles Pi-hole, a couple of *arr apps, and Uptime Kuma without breaking a sweat. It’s the wrong hardware for Immich’s photo indexing or a Plex library that needs 4K transcoding. Those want a mini PC or a proper server, not a Pi.
What throughput to actually expect
A Pi 4 or 5’s Gigabit Ethernet realistically pushes around 110MB/s, and a USB 3.0 drive can mostly keep up with that for sequential transfers, so copying a media library or backing up a laptop over the network works fine. It’s not going to compete with a 10GbE NAS, and random I/O, lots of small files rather than one big transfer, is where the Pi’s SoC and the USB storage stack both show their limits first. Treat this as a NAS for a home media library and backups, not shared production storage for a household of heavy simultaneous users.
Where this fits
If OMV vs. TrueNAS vs. Unraid is still an open question, the OpenMediaVault comparison covers the license, storage architecture, and where each one makes sense. And if this Pi is also handling Pi-hole or Home Assistant, the Raspberry Pi homelab guide covers what else realistically fits on the same board before performance starts to suffer.