NAS Drive Compatibility

Western Digital Red 2TB

NAS HDD

Part number WD20EFRX · Red series · 3.5" SATA HDD. If your machine is listed below, this drive is officially supported — not a forum workaround.

Red NAS HARD DRIVE3.5" SATA HDDWESTERN DIGITAL

Part of the Western Digital Red series →

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140
Compatible NAS models
133 Syn · 0 QNAP · 7 Asus · 0 TM
By vendor
2 TB
Listed capacity
Western Digital
Manufacturer
NAS (older line)
Product line (manufacturer rating)
5400
Spindle speed (RPM)
CMR/SMR
Recording
256 MB
Cache
180 TB
Rated workload / year

Specifications are the manufacturer's published ratings for this product series; verify the exact part number before purchase.

Strong pick as a cold 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.

Compatibility verdict

It appears on the official compatibility lists of 140 machines and series — 133 Synology, 7 Asustor. 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

Synology DS1019+5-bay See its full HCL → Synology DS1111-bay See its full HCL → Synology DS1121-bay See its full HCL → Synology DS112+1-bay See its full HCL → Synology DS112j1-bay See its full HCL → Synology DS1141-bay See its full HCL → Synology DS1151-bay See its full HCL → Synology DS115j1-bay See its full HCL → Synology DS1161-bay See its full HCL → Synology DS1181-bay See its full HCL → Synology DS119j1-bay See its full HCL → Synology DS120j1-bay See its full HCL → Synology DS1511+5-bay See its full HCL → Synology DS1512+5-bay See its full HCL → Synology DS1513+5-bay See its full HCL → Synology DS15155-bay See its full HCL → Synology DS1515+5-bay See its full HCL → Synology DS15175-bay See its full HCL → Synology DS1517+5-bay See its full HCL → Synology DS1618+6-bay See its full HCL → Synology DS1812+8-bay See its full HCL → Synology DS1813+8-bay See its full HCL → Synology DS1815+8-bay See its full HCL → Synology DS18178-bay See its full HCL → Synology DS1817+8-bay See its full HCL → Synology DS1819+8-bay See its full HCL → Synology DS2015xs See its full HCL → Synology DS2112-bay See its full HCL → Synology DS211+2-bay See its full HCL → Synology DS211j2-bay See its full HCL → Synology DS2122-bay See its full HCL → Synology DS212+2-bay See its full HCL → Synology DS212j2-bay See its full HCL → Synology DS2132-bay See its full HCL → Synology DS213air2-bay See its full HCL → Synology DS213j2-bay See its full HCL → Synology DS2142-bay See its full HCL → Synology DS214+2-bay See its full HCL → Synology DS214play2-bay See its full HCL → Synology DS214se2-bay See its full HCL → Synology DS215+2-bay See its full HCL → Synology DS215j2-bay See its full HCL → Synology DS2162-bay See its full HCL → Synology DS216+2-bay See its full HCL → Synology DS216+II2-bay See its full HCL → Synology DS216j2-bay See its full HCL → Synology DS216play2-bay See its full HCL → Synology DS216se2-bay See its full HCL → Synology DS2182-bay See its full HCL → Synology DS218+2-bay See its full HCL → Synology DS218j2-bay See its full HCL → Synology DS218play2-bay See its full HCL → Synology DS220j2-bay See its full HCL → Synology DS2411+12-bay See its full HCL → Synology DS2413+12-bay See its full HCL → Synology DS2415+12-bay See its full HCL → Synology DS3018xs12-bay See its full HCL → Synology DS3611xs12-bay See its full HCL → Synology DS3612xs12-bay See its full HCL → Synology DS3615xs12-bay See its full HCL → Synology DS3617xs12-bay See its full HCL → Synology DS3617xsII12-bay See its full HCL → Synology DS4114-bay See its full HCL → Synology DS411+4-bay See its full HCL → Synology DS411+II4-bay See its full HCL → Synology DS411j4-bay See its full HCL → Synology DS412+4-bay See its full HCL → Synology DS4134-bay See its full HCL → Synology DS413j4-bay See its full HCL → Synology DS4144-bay See its full HCL → Synology DS414j4-bay See its full HCL → Synology DS415+4-bay See its full HCL → Synology DS415play4-bay See its full HCL → Synology DS4164-bay See its full HCL → Synology DS416j4-bay See its full HCL → Synology DS416play4-bay See its full HCL → Synology DS4184-bay See its full HCL → Synology DS418j4-bay See its full HCL → Synology DS418play4-bay See its full HCL → Synology DS420j4-bay See its full HCL → Synology DS712+7-bay See its full HCL → Synology DS713+7-bay See its full HCL → Synology DS7157-bay See its full HCL → Synology DS716+7-bay See its full HCL → Synology DS716+II7-bay See its full HCL → Synology DS718+7-bay See its full HCL → Synology DS916+4-bay See its full HCL → Synology DS918+4-bay See its full HCL → Synology DVA3219 See its full HCL → Synology RS10613xs+ See its full HCL → Synology RS18016xs+ See its full HCL → Synology RS212 See its full HCL → Synology RS214 See its full HCL → Synology RS217 See its full HCL → Synology RS2211+ See its full HCL → Synology RS2211RP+ See its full HCL → Synology RS2212+ See its full HCL → Synology RS2212RP+ See its full HCL → Synology RS2414+ See its full HCL → Synology RS2414RP+ See its full HCL → Synology RS2416+ See its full HCL → Synology RS2416RP+ See its full HCL → Synology RS2418+ See its full HCL → Synology RS2418RP+ See its full HCL → Synology RS2818RP+ See its full HCL → Synology RS3411RPxs See its full HCL → Synology RS3411xs See its full HCL → Synology RS3412RPxs See its full HCL → Synology RS3412xs See its full HCL → Synology RS3413xs+ See its full HCL → Synology RS3614RPxs See its full HCL → Synology RS3614xs See its full HCL → Synology RS3614xs+ See its full HCL → Synology RS3617RPxs See its full HCL → Synology RS3617xs See its full HCL → Synology RS3617xs+ See its full HCL → Synology RS3618xs See its full HCL → Synology RS4017xs+ See its full HCL → Synology RS411 See its full HCL → Synology RS812 See its full HCL → Synology RS812+ See its full HCL → Synology RS812RP+ See its full HCL → Synology RS814 See its full HCL → Synology RS814+ See its full HCL → Synology RS814RP+ See its full HCL → Synology RS815 See its full HCL → Synology RS815+ See its full HCL → Synology RS815RP+ See its full HCL → Synology RS816 See its full HCL → Synology RS818+ See its full HCL → Synology RS818RP+ See its full HCL → Synology RS820+ See its full HCL → Synology RS820RP+ See its full HCL → Asustor AS 10 See its full HCL → Asustor AS 31/32 See its full HCL → Asustor AS 50/51 See its full HCL → Asustor AS 61/62 See its full HCL → Asustor AS 63/64 See its full HCL → Asustor AS 70 See its full HCL → Asustor AS6004U See its full HCL →

Same-capacity alternatives

Other drives listed at 2 TB capacity, ranked by how many machines list them:

Western Digital WD2005VBYZ 451 machines · Gold Toshiba MG04ACA200E 416 machines · MG04ACA**** Seagate ST2000NE0015 372 machines · Enterprise NAS HDD Toshiba MG04ACA200N 357 machines · MG04ACA**** Seagate ST2000NM0033 353 machines · Constellation ES.3 Seagate ST2000NM001A 338 machines · Exos 7E8 Seagate ST2000NM0125 320 machines · Exos 7E8 Western Digital WD2005FBYZ 320 machines · Gold

Quick answers

Is the WD20EFRX officially compatible with my NAS?

It appears on the official compatibility lists of 140 machines and series — 133 Synology, 7 Asustor. Every machine page linked below shows the vendor's own list entry, refreshed daily.

Is the WD20EFRX CMR or SMR?

As a Western Digital 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 WD20EFRX 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 WD20EFRX 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 WD20EFRX?

At the same capacity, the most widely listed alternatives are Western Digital WD2005VBYZ (451 machines), Toshiba MG04ACA200E (416 machines), Seagate ST2000NE0015 (372 machines). The full ranked list is below.