Building a NAS involves several genuinely important hardware decisions beyond simply “buy some hard drives” — a practical checklist covering what actually matters most.
The Essential Hardware Checklist
- CPU — genuinely modest requirements for basic file serving; more genuinely matters for running additional services (transcoding, containers, virtual machines) on top
- RAM — 8GB minimum is genuinely reasonable; ZFS specifically benefits meaningfully from more RAM for its own caching (ARC), a real factor worth considering if using ZFS specifically
- Drive bays — plan realistically for actual future expansion, not just your current, immediate capacity needs — adding drives later is meaningfully easier than a full, disruptive rebuild
- ECC RAM support — genuinely worth prioritizing for a NAS specifically, since silent memory errors can corrupt data before it’s even written to disk in the first place
- Network interface — 2.5GbE or faster is increasingly worth having if your actual network and switch can genuinely support it, since gigabit ethernet (125MB/s theoretical max) genuinely bottlenecks a modern multi-drive array’s real transfer speed
Drive Selection: NAS-Rated Drives Matter
NAS-rated drives (e.g. WD Red, Seagate IronWolf) are specifically designed and validated for genuinely 24/7 operation and multi-drive vibration tolerance - a real, meaningful difference from typical desktop-rated drives, which aren't validated or warrantied for continuous always-on multi-drive array use in the same way
Redundancy Is Not Optional
A NAS without genuine redundancy (RAID/ZFS mirroring or parity) is really just a single point of failure with extra steps — always plan for at least one drive’s worth of genuine redundancy from the very start, since retrofitting real redundancy onto an already-full, non-redundant array later is meaningfully more disruptive and complicated than planning for it from the beginning.