DIY NAS: 2026 Edition

Original Article ↗ Hacker News Discussion ↗

RAM, Caching, and ZFS Myths

  • Many comments focus on how much RAM a “pure NAS” needs. Consensus: 8–16 GB is fine for simple file serving at 1–2.5 Gbit; more RAM mainly improves caching and helps at 10 Gbit+ or with many repeated reads.
  • ZFS will aggressively use available RAM as ARC (read cache), but the old “1 GB RAM per 1 TB storage” rule is repeatedly called out as outdated and really only relevant to dedup-heavy workloads.
  • Several people report good real-world performance with 32–64 GB on medium-sized pools, but others run ZFS acceptably on as little as 2–8 GB, with lower performance.
  • Dedup is widely discouraged for home users because of RAM pressure and complexity; reflinks and special vdevs are mentioned as more modern ZFS features.

ECC, In‑Band ECC, and Data Integrity

  • Strong split on ECC: some treat it as mandatory for ZFS or “important data,” arguing that RAM bitflips undermine end‑to‑end checksumming; others say ECC is “better, not required,” especially for home use with backups.
  • In‑band ECC on modern low-power Intel boards (e.g., Odroid H4, i3‑N305) is praised as an underrated compromise, with modest performance cost.
  • There is debate over how real the “ZFS + bad RAM corrupts everything on scrub” risk is; some cite earlier analyses that this specific fear was overstated.

Drives, RAID, and Capacity vs Reliability

  • People share recent deals around ~$10/TB for large Seagate drives but note that consumer lines (Barracuda) are not marketed for NAS; some say this distinction is overblown if drives are CMR and you have redundancy and backups.
  • Used/refurb enterprise HDDs and SSDs are considered good value for many, especially in backup or cold‑storage roles, though others insist on new drives for primary pools.
  • RAID5 vs RAIDZ2/RAID6: RAID5 is seen as risky mainly due to very long rebuild times on large disks; tolerated by some for home if you have current backups and accept downtime. RAIDZ2 is generally preferred for big pools.
  • Concerns about resilver times on 20–28 TB drives drive some people away from single‑parity layouts.

DIY vs Prebuilt NAS, Power, and Overkill

  • Several argue that DIY no longer clearly beats prebuilt on cost: small 4‑bay Synology/QNAP/TerraMaster/UGREEN boxes are quiet, low‑power, and “set and forget,” often matching or beating DIY once you price motherboard, PSU, case, etc.
  • Others enjoy DIY for flexibility (Proxmox, VMs, GPU, Kubernetes) and re‑use of spare parts or used enterprise gear; they note that prebuilt units often ship with weak CPUs and limited RAM.
  • Power draw is contentious: some think obsessing over a 20–40 W difference is overblown versus cloud costs; others in high‑electricity regions carefully chase sub‑20 W idle and size PSUs down for efficiency.
  • N‑series Intel boards are praised for low idle, but their limited PCIe lanes can bottleneck NVMe speed; some prefer used AM4/old Xeon platforms for more PCIe and ECC at the cost of higher idle.

Cases, Cooling, Noise, and Dust

  • Jonsbo and Fractal Node 304/804 cases are frequently discussed. Jonsbo gets criticism for poor HDD airflow without fan changes; the Node series is praised for thermals and build quality.
  • Many swap stock fans for Noctua or cheaper Thermalright units and use software fan control to keep HDD temps in the high 30s–low 40s °C.
  • Dust in closets/pantries and network gear with terrible fan curves are recurring complaints; people want better thermal/fan design in consumer switches and ISP routers.

Motherboards, AliExpress, and Reliability

  • The specific Chinese “Topton” NAS boards are controversial. Supporters like the density (lots of SATA, multiple NICs, DC input) and low cost; skeptics worry about BIOS bugs, non‑existent firmware updates, and lack of real RMA paths.
  • Some prefer used Supermicro/ASRock Rack/enterprise boards with IPMI and ECC from eBay, arguing they’re proven and offer remote KVM; others see AliExpress as an acceptable risk for hobby setups.
  • There’s a parallel ethical debate about the article’s undisclosed affiliate links and whether that biases component choices (e.g., pushing a flashy board over more boring options).

Filesystems and NAS OS Choices

  • ZFS remains the default recommendation for serious DIY NAS, mostly via TrueNAS, but there’s increasing pushback: some dislike the appliance constraints and prefer plain FreeBSD, Debian, or NixOS with ZFS.
  • Btrfs RAID1 with scrubbing is suggested as an alternative for those wanting checksumming without ZFS complexity; others report past data loss and avoid Btrfs entirely.
  • TrueNAS is seen as great “appliance” software if you don’t want to be a sysadmin; critics warn that once you hit a bug in the GUI layer you’re in deeper water than with a plain OS.
  • Unraid, SnapRAID + mergerfs, and XigmaNAS appear as middle‑ground options, especially for mixed‑size drives and flexible expansion.

Backups, Off‑Site, Tape, and Disaster Planning

  • Multiple commenters stress that RAID is not backup and ask “what if the house burns down?” Off‑site copies (friend’s NAS, small QNAP, or cloud object storage) are repeatedly recommended.
  • LTO tape is discussed for true archival: media is cheap and robust, but drives are very expensive and only make economic sense beyond a few hundred TB. Home users can technically do it with a SAS HBA and used LTO‑5/6/7 drives, but it’s niche and operationally complex.
  • Some prefer cloud as primary for “irreplaceable” photos, with local NAS as backup, while others flip that (NAS primary, cloud/archive secondary) to keep more control.

Use‑Cases, Overengineering, and Simplicity

  • Several contributors think home NAS builds are often wildly overengineered (tens of TB, giant RAM, complex ZFS layouts) for light media and backup workloads; they advocate starting with a Pi, cheap mini‑PC, or a single‑bay Synology and learning first.
  • Others explicitly want a combined NAS/home‑lab: VMs, containers, media transcode, even AI workloads on a GPU, where higher‑end CPUs, more RAM, and 10 Gbit networking are justified.
  • There’s recurring advice to separate “must not lose data” (photos, documents) from bulk media; the former should drive redundancy, ECC, and off‑site strategy, not the entire home media library.