Best NAS hard drives for TrueNAS (ZFS)
ZFS, the filesystem under TrueNAS, is unforgiving of slow drives: resilvers and scrubs hammer every disk in the pool, and an SMR drive can stall hard during a resilver - sometimes dropping out entirely. So TrueNAS is CMR-only territory. The list below is CMR NAS and enterprise drives, ranked by measured failure rate.
| Drive | Capacity | Tech | Class | Interface | AFR | €/TB | Price | |
|---|---|---|---|---|---|---|---|---|
| 1 |
ST16000NM000J
Seagate Exos X18
|
16 TB | CMR | Enterprise | SATA | 0.22% | €27.49 | €440 |
| 2 |
WUH722626ALE6L4
WD Ultrastar DC HC590
|
26 TB | CMR | Enterprise | SATA | 0.40% | €41.42 | €1,077 |
| 3 |
WUH722222ALE6L4
WD Ultrastar DC HC570
|
22 TB | CMR | Enterprise | SATA | 0.47% | €51.11 | €1,124 |
| 4 |
ST16000NM001G
Seagate Exos X16
|
16 TB | CMR | Enterprise | SATA | 0.54% | €31.16 | €499 |
| 5 |
MG10ACA20TE
Toshiba MG10
|
20 TB | CMR | Enterprise | SATA | 0.59% | €43.30 | €866 |
| 6 |
MG11ACA24TE
Toshiba MG11
|
24 TB | CMR | Enterprise | SATA | 0.68% | €42.38 | €1,017 |
| 7 |
WUH721816ALE6Lx
WD Ultrastar DC HC550
|
16 TB | CMR | Enterprise | SATA | 0.80% | €41.25 | €660 |
| 8 |
WUH721414ALE6L4
WD Ultrastar DC HC530
|
14 TB | CMR | Enterprise | SATA | 0.81% | - | - |
| 9 |
ST12000NM001G
Seagate Exos X16
|
12 TB | CMR | Enterprise | SATA | 0.96% | €36.77 | €441 |
| 10 |
MG07ACA14TE
Toshiba MG07
|
14 TB | CMR | Enterprise | SATA | 1.18% | - | - |
| 11 |
ST14000NM001G
Seagate Exos X16
|
14 TB | CMR | Enterprise | SATA | 1.35% | €32.14 | €450 |
| 12 |
MG08ACA16Tx
Toshiba MG08
|
16 TB | CMR | Enterprise | SATA | 1.48% | €27.49 | €440 |
Ranked by measured failure rate (Backblaze AFR). $/TB shows once live prices are wired.
ZFS makes CMR non-negotiable
A scrub or resilver reads and writes across the whole pool, repeatedly. CMR drives take that in stride; SMR drives can drop to single-digit MB/s mid-resilver and turn a one-day rebuild into a multi-day gamble on a degraded pool. If you take one rule from this page: no SMR in a ZFS pool, ever.
Sizing vdevs
Match drive sizes within a vdev - ZFS plans around the smallest member - and run RAIDZ2 (double parity) once you have several large drives, for the same reason RAID 6 earns its keep elsewhere. The storage planner estimates usable capacity per layout.
Frequently asked questions
- Can I use SMR drives with ZFS / TrueNAS?
- Avoid them. SMR drives can become extremely slow under the sustained writes of a ZFS resilver, dramatically lengthening rebuilds and risking the pool. Use CMR drives for TrueNAS.
- Do TrueNAS drives need to match in size?
- Within a vdev, ZFS uses the smallest drive's capacity, so matched drives are most efficient. You can expand a pool by adding vdevs or (newer ZFS) by RAIDZ expansion, but matched CMR drives give the most predictable result.
- Are enterprise drives good for TrueNAS?
- Yes - many TrueNAS builders favour enterprise drives (Exos, Ultrastar) for their endurance and 5-year warranties, especially for always-on pools. NAS-class drives are fine for lighter home use.