Technical reference
Ubiquiti UNAS 4 specifications
UNAS-4 · official colors UNAS-4-B / UNAS-4-W · Quad-core ARM Cortex-A55 at 1.7 GHz · 4 GB · (4) 2.5/3.5-inch bays · (2) M.2 NVMe cache · 1×2.5GbE PoE+++ · UniFi Drive 3.4.5+
Complete specifications with requirements, upgrade limits and sources. For our buying judgment, reviews and prices, return to the buying guide.
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Identity
Exact-model specifications and documented limits.
| Exact manufacturer part number / configuration ID | UNAS-4[1] |
|---|---|
| Manufacturer | Ubiquiti[1] |
| Model | UNAS 4[1] |
| Official color SKUs | UNAS-4-B (Black, ComingSoon on 2026-09-11) and UNAS-4-W (White, Available); displaySku UNAS-4[1] |
| Certifications | NDAA compliant; FCC, CE, IC[2] |
Compute and memory
Exact-model specifications and documented limits.
| Processor | Quad-core ARM Cortex-A55 at 1.7 GHz[2] |
|---|---|
| Factory memory | 4 GB factory memory (official table: 4 GB)[2] NAS Compares describes LPDDR4, not user-upgradeable. |
| Physical CPU cores | 4[2] |
| Factory memory | 4 GB[2] |
| Host memory ECC | Not stated on the official 4 GB memory row. Unknown, not a confirmed no.[2] |
| Official memory upgrade path | Not offered (4 GB row only). NAS Compares: fixed 4 GB.[2][5] |
| Official memory limit | 4 GB as printed.[2] |
Storage and expansion
Exact-model specifications and documented limits.
| Cataloged drive-bay count | 4[1] M.2 positions are listed separately and are not silently added to SATA bay count. |
|---|---|
| Supported drive layout | (4) 2.5/3.5-inch drive bays and (2) M.2 NVMe bays (cache)[2] |
| Replaceable storage drives | Yes — NAS Compares describes individual click-in SATA trays (improved versus UNAS 2’s shared cage). Official UNAS 4 QIG URL exists (unas-4-w) but the SPA/PDF text was not fully extracted this round; treat tray design as reviewer + store photos pending a rendered QIG reread.[5] UNAS 2 QIG stills were rendered; UNAS 4 QIG HTML was a short SPA shell. Family tray claims are not copied as UNAS 4 official pages. |
| M.2 expansion | Yes — (2) M.2 NVMe bays for SSD cache (official). Not independent storage pools per NAS Compares and Dong Knows.[2][5] |
| Official external drive enclosure expansion | USB Drive support via (1) 5 Gbps USB-C. Not a certified external NAS expander.[2] |
| Physical M.2 slots | 2 (M.2 NVMe); official max NVMe SSD capacity 2 TiB; SSD Cache feature flagged[2] |
| SATA without a mandatory model whitelist | Reviewers used mixed third-party HDDs. Official mandatory lock versus qualified list was not extracted as a full table this round.[5][1] |
| M.2 without a mandatory model whitelist | Official NVMe compatibility text permits third-party SSDs, subject to the model capacity and cache requirements; no measured compatibility guarantee for an untested individual model.[13][2] |
| NVMe capacity and host link | Maximum supported capacity 2 TiB; compatibility guide specifies PCIe Gen3 x2 and M.2 tray requirement.[2][13] |
Network
Exact-model specifications and documented limits.
| Installed Ethernet | 1 × 2.5GbE RJ45 (2.5G/1G/100M/10M), PoE+++[2][1] |
|---|---|
| Fastest installed single network port | 2.5 Gbps[2] |
| Official network upgrade path | One installed 2.5GbE port; no supported USB Ethernet-adapter upgrade is established by the opened official table. Reviewer USB-NIC claims without an actual test are not adopted.[2] |
| Management interface | Ethernet[2] |
Software and data protection
Exact-model specifications and documented limits.
| Factory operating system | UniFi Drive (application requirement 3.4.5 and later) on UniFi OS[2] |
|---|---|
| RAID support | Official model table: RAID 5/6/10. Current support article: two-drive protection starts as RAID 1; Basic uses RAID 5 with 3+ drives, Advanced uses RAID 6 with 4+, Better Performance uses RAID 10 with 4+ even drives.[2][11] NAS Compares and Dong Knows also describe RAID 1-class two-disk use as part of Drive, but the UNAS 4 tech-specs RAID Type cell prints 5/6/10. |
| Backup through the graphical interface | Yes — UniFi Drive backup tasks (official flags: remote UNAS, CIFS/SMB, cloud).[2] |
| Backup to an independent target | Yes — remote UNAS, CIFS/SMB, and Google Drive / OneDrive / Dropbox / Amazon S3 / Backblaze B2 / Wasabi.[2] |
| Documented restore path | Snapshots flagged for instant versions; Time Machine restore is on the Mac. Help Center pool/restore pages 403 this round.[2] |
| Scheduled backup | Drive backup/snapshot features are official. Dong Knows’ first look reported daily caps on the then-current Drive 4 UI.[2][7] |
| Restore from snapshots | Yes — Snapshots flagged on the official UNAS 4 software table.[2] |
| Version retention | Snapshots exist. Dong Knows first look cited up to 256 versions per shared drive, at most daily, on that Drive 4 UI — not a numbered official cell.[2][7] |
| Immutable protection | Not established. File encryption is flagged; immutability period is not on the opened table.[2] |
| Remote snapshot replication | Backup to Remote UNAS is flagged (backup job, not documented snapshot-replication product).[2] |
| Native endpoint restore | Time Machine is supported. Client-app access is documented; full endpoint recovery, continuous photo backup and restore success are not established by feature flags alone.[2] |
| Official system update path | UniFi OS / UniFi Drive updates. Follow-up recorded Drive 4.3.10 / NAS OS 5.1.30 on the desktop pair by August 2026.[2][6] |
| System status interface | Yes — UniFi Drive dashboard and 1.47-inch color LCM.[2][5] |
| System log interface | Drive 4.x health/status additions are described in the August 2026 follow-up; a dedicated log application is not specified in the model table.[2][6] |
| File protocols | SMB and NFS[2] |
| UniFi Drive version requirement | Version 3.4.5 and later; iOS 10.32.1+ / Android 10.35.1+[2] |
| Additional Drive features (official flags) | SSD cache; personal & shared drives; file encryption; share links; client apps; user groups; Time Machine[2] |
| Storage pool and RAID group limit | One storage pool with one RAID group.[11] |
| RAID conversion boundary | The current help article limits its conversion-without-reformat procedure to UNAS Pro. No non-destructive RAID-type conversion guarantee is established here.[11] |
| File encryption | Supported in the current official feature table.[2] Launch-review text saying encryption is absent is historical and conflicts with current primary documentation. |
| SSD cache assignment | One SSD for read-only; two for mirrored read/write. Cannot add to an all-SSD pool or a legacy pool created before UniFi OS 4.3. Large sequential files bypass cache.[12] |
| SSD cache failure and removal | With mirrored read/write cache, one failure triggers write-back and read-only operation; both failing puts the pool in Failed state. Normal removal writes cached data back before formatting SSDs.[12] |
Warranty and support
Exact-model specifications and documented limits.
| Standard warranty | Official webstore: two years from delivery. Authorized distributor/reseller: one year from shipment to that distributor/reseller, not one year from the end buyer’s purchase.[3] Replacement does not restart the warranty. Confirm channel eligibility; optional UI Care is separate. |
|---|---|
| Warranty and data responsibility | Hardware repair/replacement terms exclude software and third-party products; preserve backups before RMA. Replacement does not extend the original term.[3] |
Physical, power and acoustics
Exact-model specifications and documented limits.
| Dimensions | 246 x 129 x 224.5 mm (9.7 x 5.1 x 8.8 in)[2] |
|---|---|
| Weight | 2.6 kg (5.7 lb)[2] |
| Power supply and consumption | PoE+++; 90W PoE+++ adapter included; max. 90W; max. drive budget 80W[2] |
| Acoustic conditions | Not published officially. NAS Compares: louder than UNAS 2 when four disks heat the chassis; fan profiles Quiet/Balanced/Cooling exist in Drive. No dBA table in the UNAS 4 launch review extract.[2][6] |
| USB expansion | (1) 5 Gbps USB-C; USB Drive supported[2] |
| Front display | 1.47-inch color LCM[2] |
| Bluetooth | Bluetooth 4.1[2] |
| Enclosure material | Polycarbonate[2] |
| Form factor | Desktop[2] |
| System indicator | System LED supported[2] |
| Operating temperature | -5 to 40°C (23 to 104°F)[2] |
| Operating humidity | 10–90%, non-condensing[2] |
| USB power budget | 4.5 W maximum; official drive-power note excludes cable loss.[2] |
Exact product identity & open questions
- Product ID
- ubiquiti-unas-4[1]
- Model
- UNAS 4[1]
- Official color aliases
- UNAS-4-B (black), UNAS-4-W (white)[1]
- Factory compute and memory
- Quad-core ARM Cortex-A55 at 1.7 GHz; 4 GB[2]
- Storage layout
- (4) 2.5/3.5-inch bays + (2) M.2 NVMe cache (2 TiB max)[2]
- UNAS 4 QIG stills: Official QIG URL https://ui.com/qig/unas-4-w loaded as a short SPA; drive-tray stills were not rendered like UNAS 2.
- Dong Knows UNAS 4 is a first look: No UNAS 4 throughput charts. Kept out of reviews[] measurements.
- Help Center 403: Same 403 as UNAS 2 for Time Machine / pool articles.
- Amazon / Newegg / B&H: Amazon B0GVB4GBLB intercepted; Newegg CAPTCHA; B&H search 403.
- Video: No UNAS 4 dedicated video ASR this round. Family videos not treated as UNAS 4 measurements.
- Official dBA / ECC: Not on the tech-specs table.
- SSD-pool cache conflict: Coywolf describes NVMe alongside a SATA-SSD pool, but current official instructions disallow adding cache to SSD pools. Installed devices do not establish effective caching.
Sources
Research updated Sep 11, 2026. Individual source check dates are listed below. Measurements belong to the named reviewers; tested configurations and software versions may differ from the product you buy.
- [1] Ubiquiti US Store UNAS 4 ↗
Checked Sep 11, 2026 · NEXT_DATA displaySku UNAS-4; UNAS-4-W Available $379/$408; UNAS-4-B ComingSoon
- [2] UniFi UNAS 4 tech specs ↗
Checked Sep 11, 2026 · technicalSpecification Overview/Hardware/Software; RAID 5/6/10; SSD cache 2 TiB
- [3] Ubiquiti limited warranty ↗
Checked Sep 11, 2026 · Full policy read: two years from direct delivery; one year from shipment to authorized distributor/reseller; replacement does not extend term.
- [4] UNAS 4 store historical price row ↗
Checked Sep 11, 2026 · Retained baseline source id; current money taken from 2026-09-11 NEXT_DATA
- [5] NAS Compares UniFi UNAS 4 review ↗
Checked Sep 11, 2026 · Parent read full available original written article via web; figure access limits recorded in audit.
- [6] NAS Compares UNAS 2 and UNAS 4 one year later ↗
Checked Sep 11, 2026 · Parent read full available original written article via web; figure access limits recorded in audit. Follow-up continues the same original test family.
- [7] Dong Knows UNAS 4 first take ↗
Checked Sep 11, 2026 · Full original preliminary article read; no original throughput experiment. Daily scheduling assertions are historical.
- [8] Ubiquiti US Store UNAS-4 offer ↗
Checked Sep 11, 2026 · UNAS-4-W Available $408 with surcharge
- [9] Flytec UNAS-4-W ↗
Checked Sep 11, 2026 · schema.org Offer price 379 USD, NewCondition, OutOfStock, sku UNAS-4-W
- [10] Microcom UNAS-4-B ↗
Checked Sep 11, 2026 · Item# UNAS-4-B $379.00; Usually ships in 6-8 weeks
- [11] Ubiquiti storage protection and RAID ↗
Checked Sep 11, 2026 · For UNAS: single pool/group, drive counts and RAID footnotes; Pro-only conversion is not generalized.
- [12] Ubiquiti adding SSD cache on UNAS/ENAS ↗
Checked Sep 11, 2026 · UNAS 4 explicitly included; assignment, exclusion and failure behavior.
- [13] UniFi storage requirements and compatibility ↗
Checked Sep 11, 2026 · NVMe row explicitly names UNAS-4; PCIe Gen3 x2. Generic rack-console SATA rows are not model-qualified UNAS 4 lists.
- [14] Coywolf UNAS 4 home deployment ↗
Checked Sep 11, 2026 · Jon Henshaw, published March 29 / updated June 14, 2026; original deployment and backup experience. Figures not independently recovered.
Research and review record
- Research: Grok 4.6 · Source research and data update
- Self-check: Grok 4.6 · Researcher self-check
- Independent review: GPT-6 (Codex) · Independent original written-source, table and specified figure inspection; exact-model reconciliation and dated merchant terms. Video and blocked figures excluded.
- Editorial integration: GPT-6 (Codex) · Editorial integration and validation
Independent review completed for the scope recorded in the audit.
Source evidence and review history (JSON)