Western Digital documents CMR for the WD Red Pro line at every capacity outside the SMR models its 2020 list names; this part number is not named individually. The answer comes from Western Digital internal client HDD recording technology - SMR drives by capacity (7 July 2020), which states it at FAMILY level - it does not name this part number. Families can ship mixed recording technologies, so this is the family's answer, not a verified answer for this exact drive.
We hold no vendor document that defines the segments of WD101KFBX, so we do not decode it.
Nearest model with a sourced answer: WD101EFBX (WD Red Plus 10TB, CMR). Listed for comparison only - two part numbers can use different recording methods, so its answer is not WD101KFBX's.
Live rankings this model belongs to: every 10TB hard drive. Product pages for this part number: WD Red Pro 10TB WD101KFBX.
Family-level source (states it for the family, does not name this part number): Western Digital internal client HDD recording technology - SMR drives by capacity (7 July 2020) · Checked
An earlier 10TB Red Pro. WD's current Red Pro data sheet lists WD103KFBX and WD102KFBX at this capacity instead, so the workload rating and cache are not stated here rather than assumed from its successors.
Western Digital documents CMR for the WD Red Pro line at every capacity outside the SMR models its 2020 list names; this part number is not named individually. That is useful evidence and it is not verification: a family can ship more than one recording method - WD Red is the standing example - so for a NAS or anything that rebuilds, prefer a drive whose own part number is documented. For a single drive holding replaceable data the distinction is largely academic.
| Model number | WD101KFBX |
| Brand | WD |
| Family | WD Red Pro |
| Capacity | 10TB |
| Form factor | 3.5" |
| Rotational speed | — |
| Cache | — |
| Recording technology | CMR (family level - part number not named) |
| Workload rate | — |
| Warranty | — |
| Status | Discontinued |
| 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.
Western Digital documents CMR for the WD Red Pro line at every capacity outside the SMR models its 2020 list names; this part number is not named individually. So the family answer is CMR, from Western Digital internal client HDD recording technology - SMR drives by capacity (7 July 2020); we have not found a document that names this exact part number.
The recording technology is unsourced, so we cannot clear it for arrays either way. What the spec table does say: no stated workload rating and no stated warranty. For an array, prefer a 10TB drive whose recording technology is sourced, such as the WD101EFBX (CMR).