WD30EFAX - CMR or SMR?

SMR

The WD WD Red 3TB (WD30EFAX) uses SMR recording.

Verified against: WD Red NAS HDD product brief ยท Checked

Sources disagree on this model

WD's own Red product brief prints SMR against this model, footnoted as device-managed SMR.

What this means for you

Shingled recording overlaps tracks like roof tiles to raise density. Reading is unaffected, and for sequential work, archives, media libraries, backup targets, files written once and read many times, this drive is genuinely fine and the saving is real. The problem is sustained random writing, because modifying data under an existing track can force the tracks above it to be rewritten too. A RAID rebuild or a ZFS resilver is hours of exactly that pattern with no idle time to recover, so a 3TB WD30EFAX in an array can extend a rebuild dramatically, and the rebuild window is precisely when the array has no redundancy left. Do not put this drive in a NAS or a parity array.

Specifications

Model numberWD30EFAX
BrandWD
FamilyWD Red
Capacity3TB
Form factor3.5"
Rotational speed5400 RPM
Cache256 MB
Recording technologySMR
Workload rate180 TB/year
Warranty3 years
StatusCurrent
Replaced byโ€”

A dash means the manufacturer does not state that field for this exact model. We leave it blank rather than filling it from a retailer listing.

Need CMR at this capacity?

If this drive is going into an array, a NAS, or anything that rebuilds, shingled recording is the wrong choice at any price. These are conventionally-recorded drives at this capacity or one step up, in stock right now with live prices.

DriveCapacityRecording$/TBPrice
HUS724030ALS640 3TB SAS 6G3TBCMR$15.13$45Buy
Constellation ES.2 3TB SAS Enterprise3TBCMR$16.00$48Buy
Constellation ES.2 3TB SAS3TBCMR$17.00$51Buy

Verified CMR model numbers at this size: ST3000VX009, DT01ACA300, HDWD130, WD30EFZX.

Related models

Other WD Red capacities
WD20EFAX2TBSMRWD40EFAX4TBSMRWD60EFAX6TBSMRWD80EFAX8TBCMRWD100EFAX10TBCMRWD120EFAX12TBCMR
The same capacity from other makers
ST3000VX0093TBCMRDT01ACA3003TBCMRHDWD1303TBCMR
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Frequently asked questions

Is the WD30EFAX CMR or SMR?

It is SMR. That comes from WD Red NAS HDD product brief, which is WD's own documentation for this exact part number rather than a capacity-level summary or a retailer listing.

Can I use the WD30EFAX in a NAS or RAID array?

We would not. Shingled recording turns a rebuild into hours of the write pattern it handles worst, which can extend the window during which your array has no redundancy. For sequential and archival use outside an array this drive is fine.

What should I buy instead of the WD30EFAX for a NAS?

A conventionally-recorded drive at 3TB or one step up. The table above lists what is in stock right now with live prices, and every model number linked there has its own verified page with the manufacturer source.

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