Overview
The Ubiquiti UNAS-4-B is a black UniFi Network Attached Storage system with four 2.5/3.5-inch drive bays and two M.2 NVMe SSD slots for caching. It provides 2.5GbE networking, 5Gbps USB-C connectivity, integrated UniFi Drive management, and a compact desktop form factor.
Storage and Performance
The UNAS 4 supports up to four 2.5-inch or 3.5-inch HDDs and two M.2 NVMe SSDs. NVMe drives can be used for SSD caching, with support for NVMe SSD capacities up to 2TB per supported cache configuration. Supported RAID types include RAID 5, RAID 6, and RAID 10.
Network and Connectivity
Network connectivity is provided through a 2.5GbE RJ45 interface supporting 2.5G, 1G, 100M, and 10M Ethernet. A 5Gbps USB-C expansion port supports USB storage and other compatible peripherals. Bluetooth 4.1 is also integrated.
UniFi Storage Features
UniFi Drive provides shared and personal drive functionality with SMB and NFS file protocols. The system also supports file encryption, snapshots, share links, Time Machine backups, remote UNAS backups, CIFS/SMB server backups, and backup destinations including Google Drive, OneDrive, Dropbox, Amazon S3, Backblaze B2, and Wasabi.
Key Features
- Four 2.5/3.5-inch HDD bays for network storage
- Two M.2 NVMe SSD slots for SSD caching
- 2.5GbE RJ45 networking with multi-speed Ethernet support
- 5Gbps USB-C expansion port and Bluetooth 4.1
- Included 90W PoE+++ power adapter
Applications
The UNAS-4-B is designed for centralized file storage, shared network drives, workstation backups, media storage, and other UniFi-managed storage deployments. Its four drive bays and supported RAID configurations allow storage capacity and redundancy to be planned around the requirements of the deployment.
DC Supplies Product Note
The UNAS-4-B is supplied without storage drives, so HDD and NVMe selection should be planned separately according to the required capacity, RAID configuration, and caching requirements.
Specifications
| Specification | Details |
|---|
| Brand | Ubiquiti |
| Part Number / MPN | UNAS-4-B |
| Product Type | Network Attached Storage |
| Product Family | UniFi UNAS 4 |
| Color | Black |
| Form Factor | Desktop |
| Drive Bays | 4 × 2.5/3.5-inch HDD |
| M.2 Slots | 2 × M.2 NVMe SSD |
| Maximum NVMe SSD Capacity Supported | 2TB |
| Networking Interface | 1 × 2.5GbE RJ45 |
| Ethernet Speeds | 2.5G / 1G / 100M / 10M |
| Expansion Port | 1 × 5Gbps USB-C |
| Wireless Interface | Bluetooth 4.1 |
| Processor | Quad-Core ARM Cortex-A55, 1.7GHz |
| System Memory | 4GB |
| Supported RAID | RAID 5, RAID 6, RAID 10 |
| Supported File Protocols | SMB, NFS |
| SSD Cache | Supported |
| Maximum Power Budget for Drives | 80W |
| Maximum Power Consumption | 90W |
| Power Method | PoE+++ |
| Power Supply | 90W PoE+++ adapter, included |
| Display | 1.47-inch color LCM |
| Enclosure Material | Polycarbonate |
| Dimensions | 246 × 129 × 224.5 mm |
| Weight | 2.6 kg |
| Operating Temperature | -5°C to 40°C |
| Operating Humidity | 10–90% noncondensing |
| Certifications | FCC, CE, IC |
| NDAA Compliant | Yes |
FAQs
How many drives can the UNAS-4-B hold?
The system has four bays supporting 2.5-inch and 3.5-inch HDDs, plus two M.2 NVMe SSD slots.
Does the UNAS-4-B include hard drives?
No. The storage drives are not included and must be selected separately.
What network speed does the UNAS 4 support?
It has one 2.5GbE RJ45 network interface supporting 2.5G, 1G, 100M, and 10M Ethernet.
Which RAID modes are supported?
The UNAS 4 supports RAID 5, RAID 6, and RAID 10.
Can NVMe SSDs be used for caching?
Yes. The two M.2 NVMe slots support SSD caching, with a maximum supported NVMe SSD capacity of 2TB.
