A NAS (Network-Attached Storage) is just a computer whose job is to hold drives and share them over your network. You don't need to buy a pre-built box — a spare PC, an old server, or even a Raspberry Pi with a USB hub can work depending on how much storage and performance you need.
1. Pick your hardware
- Repurposed PC/server: cheapest option if you already have one — just needs enough SATA/USB ports for your drives.
- Dedicated NAS board (e.g. mini-ITX build): more power-efficient for 24/7 use, worth it if this'll run constantly.
- Raspberry Pi + USB enclosure: fine for light use (a few users, modest speeds), not ideal for heavy simultaneous access.
- Drives: use NAS-rated drives (e.g. WD Red, Seagate IronWolf) if you can — they're built for 24/7 spinning and vibration in multi-drive enclosures, unlike standard desktop drives.
2. Decide on redundancy
More than one drive means you can tolerate a drive failure without losing data — but only if you set it up that way:
- RAID 1 / mirroring: two drives holding identical copies. Simple, wastes half your capacity, survives one drive failure.
- RAID 5 / RAIDZ1: three or more drives, one drive's worth of capacity spent on parity. Survives one drive failure.
- No redundancy (JBOD/single disk): simplest, cheapest, and one drive failure means data loss. Fine for pure backups you keep copies of elsewhere, risky as your only copy.
RAID is not a backup. It protects against a drive failing, not against ransomware, accidental deletion, or the whole box dying. Keep an actual backup of anything irreplaceable somewhere else.
3. Pick an OS
- TrueNAS (Core/Scale): ZFS-based, strong data-integrity features (checksums, snapshots), steeper learning curve.
- Unraid: paid license, very flexible mixed-drive-size arrays, popular for combining NAS + app/VM hosting.
- OpenMediaVault (OMV): free, Debian-based, lighter-weight and beginner-friendly.
- Plain Linux + Samba/NFS: full manual control, no GUI hand-holding — good if you want to actually learn the underlying pieces.
4. Share it on your network
- SMB (Samba): what Windows (and most NAS OSes) use by default — works fine from macOS and Linux too.
- NFS: lighter-weight, common choice if every client is Linux.
- Set up separate shares per purpose (e.g. media, backups, documents) rather than one giant share — makes permissions and organization much easier later.
5. Basics worth doing from day one
- Set a static IP (or a DHCP reservation) so the NAS's address doesn't change on you.
- Enable email/notification alerts for drive health (SMART) if your OS supports it — catching a failing drive early is the whole point of redundancy.
- Change default admin credentials immediately, and don't expose the management UI directly to the internet.
- Schedule at least one off-box backup of anything that isn't reproducible.