The WD Red Pro 12TB (WD121KFBX) uses CMR recording.
Live rankings this model belongs to: every 12TB hard drive. Product pages for this part number: WD Red Pro 12TB WD121KFBX.
Verified against: WD Red Pro NAS HDD data sheet · Checked
Conventional recording writes tracks side by side without overlap, so a write never forces the drive to rewrite neighbouring data. That makes the WD121KFBX safe for every use including RAID, ZFS, a NAS, and anything with sustained random writes. A rebuild or a resilver on this drive behaves the way the array expects, which is the whole reason the distinction matters. There is no recording-technology reason to avoid this drive for any workload.
| Model number | WD121KFBX |
| Brand | WD |
| Family | WD Red Pro |
| Capacity | 12TB |
| Form factor | 3.5" |
| Rotational speed | 7200 RPM |
| Cache | 256 MB |
| Recording technology | CMR |
| Workload rate | 550 TB/year |
| Warranty | 5 years |
| Status | Current |
| Replaced by | — |
A dash means we have not found a manufacturer document stating that field for this exact model. We leave it blank rather than filling it from a retailer listing.
It is CMR, per WD Red Pro NAS HDD data sheet - WD's documentation for this exact part number - which also rates it at 550TB/year workload; its closest tracked rival at this capacity is the ST12000DM001.
Yes: WD Red Pro NAS HDD data sheet states CMR for the WD121KFBX, and conventional recording means a write never forces neighbouring tracks to be rewritten, so rebuilds and resilvers behave normally. Check the workload rating and warranty for your duty cycle separately.