ST18000NM000J - CMR or SMR?

CMR

The Seagate Exos X 18TB (ST18000NM000J) uses CMR recording.

Verified against: Seagate Exos X series product page ยท Checked

What this means for you

Conventional recording writes tracks side by side without overlap, so a write never forces the drive to rewrite neighbouring data. That makes the ST18000NM000J 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.

Specifications

Model numberST18000NM000J
BrandSeagate
FamilyExos X
Capacity18TB
Form factor3.5"
Rotational speed7200 RPM
Cache256 MB
Recording technologyCMR
Workload rate550 TB/year
Warranty5 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.

Related models

Other Exos X capacities
ST4000NM000A4TBCMRST8000NM000A8TBCMRST10000NM056810TBCMRST12000NM001G12TBCMRST14000NM001G14TBCMRST16000NM001G16TBCMRST20000NM007D20TBCMRST24000NM002H24TBCMR
The same capacity from other makers
HDWG18018TBCMRMG09ACA18TE18TBCMRWD181KFGX18TBCMR
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Frequently asked questions

Is the ST18000NM000J CMR or SMR?

It is CMR. That comes from Seagate Exos X series product page, which is Seagate's own documentation for this exact part number rather than a capacity-level summary or a retailer listing.

Can I use the ST18000NM000J in a NAS or RAID array?

Yes. Conventional recording means a write never forces neighbouring tracks to be rewritten, so rebuilds and resilvers behave normally. There is no recording-technology objection to this drive in an array, check the workload rating and warranty for your duty cycle separately.

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