With an Intel quad-core processor, the devices main frequency reaches up to 1.5 GHz (max turbo to 2.3 GHz). It achieves read speeds of 119 MB/s and write speeds up to 118 MB/s, supports AES NI hardware encryption, and is ideal for small to medium commercial storage servers with 4GB DDR3 memory and four 1000Mbps network interfaces.
6-layer data security protection
The F5-421 device relies on the following six data security layers:
Automatic scheduled backup Btrfs file system and snapshot Multi RAID array security AES hardware folder encryption and network transport encryption Cloud drive data backup File system Cluster
Enhance the Safety of your Data with a Next-Generation File System
Superior storage technology and optimised snapshot technology are the cornerstones of the Btrfs file system, which is what TerraMasters F5-421 5-bay NAS unit relies on for advanced data protection, prevention of data corruption, and minimal maintenance expenses. Use of this file system promotes high data integrity, all the while promoting flexibility and efficiency in the areas of data protection and data recovery. Optimised snapshot technology generates 1024 snapshots for every shared folder, and up to 8,192 overall system snapshots. In this way, users can benefit from flexible, storage-saving data protection. Since data recovery takes place at the file or folder level, businesses can also benefit from enhanced flexibility and efficient data recovery.
Faster and Safer
The device is equipped with four Gigabit network interfaces to support network aggregation and failover. If one network interface fails, the Internet connection can be maintained, helping to reduce the possibility of service interruption and the inconvenience of downtime operation. In addition, network aggregation can give full play to the advantages of the four network interfaces, which several times faster the connection speed and breaks the speed limit of a single network interface.
Large-Scale User Access
Support concurrent access for up to 1,000 users. You can also share storage space across multiple users, apply RBAC rights management and Windows ACL, and set access rights according to users, user groups, and folders.
Using SSD acceleration technology, transmission efficiency can be enhanced with a read-write optimised combination of hard disk and SSD cache. Effective SSD acceleration technology dramatically reduces I/O latency and improves storage efficiency by more than 20%.
Multiple RAID Modes
Support a variety of disk array modes, including RAID 0, RAID 1, RAID 5, RAID 6, RAID 10, JBOD, and SINGLE, to meet the needs of various users and levels of data security.
A Private Space in the Cloud
TNAS offers users the opportunity to establish a personal cloud drive that satisfies their remote access needs. Rights of access can be tailored for your colleagues, relatives, or friends, and with support for two-way sync cloud drive, enjoying the benefits of convenient cloud life has never been easier.
TNAS.online for Simple Remote Access
TNAS.online spares you from setting up DDNS, complicated network settings, and further port forwarding rules when trying to access files on TNAS through the Internet. At no additional expense, the service provides a secure, modifiable URL that you can use to engage with audio and video content, along with other work files, on your Internet-enabled device.
Striving to Satisfy Small and Medium Businesses
Small businesses benefit from the opportunity to conveniently build file storage servers, mail servers, web servers, FTP servers, MySQL databases, CRM systems, Node.js, and Java virtual machines, as well as a host of other commercial applications.
State-of-the-Art TOS 4.1.X Operating System
With the most recent version of the TOS operating system, TOS 4.1.X, you can back up your data, manage your file server, and optimise your sharing services in an intuitive, simple, and user-friendly way. The operating system includes a complex of application software, with rich application content, potent multimedia services, and numerous ways to back up your data.
Smart Mobile App
With the TNAS mobile app, quickly access your TNAS device and its multimedia data without restrictions, all simply through your iOS or Android system.
F5-421 - PRODUCTS
Intel® Celeron® J3455
Quad Core 1.5GHz (Max burst up to 2.3GHz)
Hardware Encryption Engine
Pre-installed Memory module
Total Memory Slot Number
Maximum Supported Memory
8 GB (4 GB + 4 GB)
TerraMaster reserves the right to replace memory modules with the same or higher frequency based on supplier's product life cycle status. Rest assured that the compatibility and stability have been strictly verified with the same benchmark to ensure identical performance.
Disk Slot Number
Compatible Drive types
3.5' SATA HDD
2.5' SATA HDD
2.5' SATA SSD
Maximum Internal Raw Storage Capacity
80TB (16TB x 5) (Capacity may vary by RAID types)
Max Single Volume
Drive Hot Swap
. Hard drive vendors will release their latest models of hard drives, and Maximum internal raw storage capacity may be adjusted accordingly. . The maximum single volume size is not directly related to the maximum raw capacity.
EXT3, EXT4, NTFS, FAT32, HFS+
RJ-45 1GbE Network Jack
USB 3.0 Port
USB 2.0 Port
LSI 9207-8i HBA Card
227 x 225 x 136 mm
Packaging Size (H*W*D)
300 x 275 x 186 mm
Net Weight: 2.30Kg Gross Weight: 3.56Kg
80 mm x 80 mm x25mm 2 pcs
Smart, High speed, Middle speed, Low speed
AC Input Voltage
100V - 240V AC
50/60 Hz, Single frequency
46.6W (read & write)
FCC, CE, CCC, KC
5°C ~ 40°C (40°F ~ 104°F)
-20°C ~ 60°C (-5°F ~ 140°F)
5% ~ 95% RH
Host unit (x1)
Power cord (x1)
RJ-45 network cable (x1)
Quick Installation Guide (x1)
Limited Warranty Note(x1)
Power adapter (x1)
Supported Client OS
Windows OS, Mac OS, Linux OS
Supported Web Browsers
Google Chrome 48, Microsoft Internet Explorer 9, Mozilla Firefox 30,Apple Safari 4.5 or later version; Microsoft Edge is not recommened.