Western Digital WD RED 12 TB
NAS HDD
Part number WD120EFAX · WD RED series · 3.5" SATA HDD. If your machine is listed below, this drive is officially supported — not a forum workaround.
Part of the Western Digital WD RED series →
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Specifications are the manufacturer's published ratings for this product series; verify the exact part number before purchase.
Recording for this series is mixed CMR/SMR — it varies by exact model number. Verify the exact part number before buying a cold copy: SMR drives throttle writes once their internal cache is full, which is exactly what a full-library backup pass does — a 16 TB cold-copy backup that takes days will slow to crawl on the last terabytes. For the off-site slot of a 3-2-1 plan, prefer the CMR variant of the same capacity; the 3-2-1 guide and the backup tools encyclopedia cover the rest of the chain.
Compatibility verdict
It appears on the official compatibility lists of 48 machines and series — 48 TerraMaster. This is a NAS-class drive: built for 24/7 operation with vibration compensation for multi-bay enclosures — the right tier for most 1-8 bay home or small-office NAS units. Its series rating is on file as SMR (shingled) — the one trait that slows large RAID rebuilds and full-library copies.
Compatible NAS models
Same-capacity alternatives
Other drives listed at 12 TB capacity, ranked by how many machines list them:
Quick answers
Is the WD120EFAX officially compatible with my NAS?
It appears on the official compatibility lists of 48 machines and series — 48 TerraMaster. Every machine page linked below shows the vendor's own list entry, refreshed daily.
Is the WD120EFAX CMR or SMR?
As a Western Digital WD RED drive, it is rated CMR/SMR varies by model. CMR (conventional magnetic recording) is what a RAID array wants: SMR drives slow rebuilds dramatically. This series mixes both, so verify the exact part number before buying — the <a href="/faq/cmr-vs-smr-nas-drives/">CMR vs SMR guide</a> has a part-number lookup.
Is the WD120EFAX a good NAS drive?
This is a NAS-class drive: built for 24/7 operation with vibration compensation for multi-bay enclosures — the right tier for most 1-8 bay home or small-office NAS units. Its series rating is on file as SMR (shingled) — the one trait that slows large RAID rebuilds and full-library copies.
Can I use the WD120EFAX for a 3-2-1 cold backup copy?
Recording for this series is mixed CMR/SMR — it varies by exact model number. Verify the exact part number before buying a cold copy: SMR drives throttle writes once their internal cache is full, which is exactly what a full-library backup pass does — a 16 TB cold-copy backup that takes days will slow to crawl on the last terabytes. For the off-site slot of a 3-2-1 plan, prefer the CMR variant of the same capacity; the 3-2-1 guide and the backup tools encyclopedia cover the rest of the chain.
What are alternatives to the WD120EFAX?
At the same capacity, the most widely listed alternatives are Western Digital WD121KRYZ (381 machines), Toshiba MG07ACA12TE (329 machines), Seagate ST12000NM0008 (315 machines). The full ranked list is below.