6 Best Alternatives to the Synology 4-Bay Rackmount NAS Redundant (2026)

How each alternative compares

BUFFALO TeraStation 5420RN 16TB Rackmount NAS

The BUFFALO TeraStation 5420RN offers 16TB of pre-installed storage, whereas the Synology RS826RP+ is diskless. BUFFALO includes 10GbE networking for higher throughput, while the Synology relies on standard Gigabit ports. This model prioritizes security features and encryption over software flexibility. It is a heavier unit at 27.2 pounds, compared to the Synology's lighter frame. You should choose this if you need immediate storage capacity and faster network speeds. The Synology is better if you want to scale capacity later using expansion units. The BUFFALO is a complete solution for secure, high-speed business data storage without the need for separate drive purchases.

Asustor Lockerstor 4-Bay 10GbE NAS

The Asustor AS6804T distinguishes itself with 16GB of ECC RAM and a quad-core AMD Ryzen processor. The Synology RS826RP+ lacks dedicated ECC memory and uses a different processor architecture. Asustor also includes both 5GbE and 10GbE ports, offering superior network flexibility compared to the Synology's standard connectivity. This NAS is heavier and larger, measuring 12x10x13 inches. It is designed for performance-focused setups that require robust memory handling. You should pick the Asustor if you prioritize raw processing power and high-speed networking. The Synology is a better fit if you value seamless capacity expansion through its RX426 expansion unit and prefer a simpler, license-free backup suite.

Synology 4-Bay Rackmount Expansion Unit

The Synology RX418 is an expansion unit, not a standalone NAS. It adds four additional drive bays to your existing Synology setup. The RS826RP+ is a complete 4-bay server with redundant power supplies and a built-in processor. The RX418 cannot operate independently and requires a host NAS to function. It is significantly smaller, measuring 17x11.4x1.73 inches. This product is ideal if you already own a Synology NAS and need more storage space. It allows you to scale from 4 to 8 drive bays easily. If you need a complete server with redundant power and high uptime, the RS826RP+ is the correct choice. The RX418 is purely for capacity expansion within the Synology ecosystem.

G-Technology 32TB G-Speed Shuttle

The G-Technology G-Speed Shuttle uses Thunderbolt 3 connectivity, unlike the Ethernet-based Synology RS826RP+. It comes with 32TB of pre-installed storage, while the Synology is diskless. This unit features hardware RAID, making it suitable for direct workstation connections. It is a transportable drive, measuring 9.75x6.85x10.5 inches and weighing 16 pounds. The Synology is a rackmount server designed for network-wide access and redundancy. You should choose the G-Technology if you need high-speed Thunderbolt 3 connections for video editing workflows. The Synology is better for office environments requiring redundant power and scalable network storage. This G-Technology model lacks network redundancy features found in the RS826RP+.

QNAP 4-Bay USB-C Hardware RAID Enclosure

The QNAP TR-004 is a Direct Attached Storage (DAS) unit, not a network-attached server. It connects via USB-C, whereas the Synology RS826RP+ connects over Ethernet. The QNAP lacks network redundancy and independent operation capabilities. It is designed to expand storage for a single PC or as a backup target for an existing NAS. The unit is diskless and measures 8.62x6.31x6.63 inches. You should pick this if you need local storage expansion for a workstation. The Synology is better if you need a dedicated network server with redundant power supplies. The QNAP offers simplicity for local storage needs, while the Synology provides full network NAS functionality and high-uptime protection for office applications.

QNAP 4-Bay USB-C Direct Attached Storage

The QNAP TR-004 is another DAS option, similar to the previous entry but with a black finish. It connects via USB-C and lacks network interfaces. The Synology RS826RP+ is a full network server with redundant power and Ethernet connectivity. This QNAP unit is diskless and designed for simple hardware RAID configurations. It measures 4 Bay in size, with specific dimensions not fully detailed beyond bay count. It is suitable for users who need local storage expansion or backup space for existing systems. You should choose this if you prefer simple hardware RAID over complex network setups. The Synology is the better choice for network-wide access, redundant power, and scalable capacity. This QNAP model does not offer the high-uptime features of the RS826RP+.

Quick picks

Our 7 picks

1 Best overall

Synology 4-Bay Rackmount NAS with Redundant Power

Best for: offices needing redundant power and scalable capacity

Drive Bays

4-Bay

Included Storage

Diskless

Weight

23 pounds

View on Amazon: Synology 4-Bay Rackmount NAS with Redundant Power Affiliate link

The Synology RS826RP+ is a 4-bay rackmount NAS designed for high availability. It features dual redundant power supplies to maintain uptime during failures. The system delivers over 2,000 MB/s sequential read speeds. You can expand capacity by connecting an RX426 expansion unit. This unit supports comprehensive backup solutions for physical and virtual systems. It suits offices needing reliable, scalable storage infrastructure.

Pros

• Dual built-in redundant power supplies for continuous operation
• Over 2,000 MB/s sequential read throughput
• Expandable from 4 to 8 drive bays via RX426
• Includes license-free backup suite for VMs and cloud

Cons

• Sold diskless without pre-installed hard drives
• Larger physical footprint than desktop NAS units
• Requires rackmount installation rather than desk placement

Good fit if

• You need redundant power to prevent downtime
• You require high sequential read speeds for office apps
• You plan to expand storage capacity later

Skip if

• You want a pre-loaded drive solution
• You prefer compact desktop storage over rackmount
• You need immediate plug-and-play without expansion planning

Verdict: Synology RS826RP+ 4-Bay Rackmount NAS offers robust redundancy and speed for offices requiring scalable, high-uptime storage infrastructure.

2 Best rackmount

BUFFALO TeraStation 5420RN 16TB Rackmount NAS

Best for: Secure business data storage with 10GbE

Drive Bays

4-Bay

Network Connectivity

Native 10GbE port

Included Storage

16TB (4x4TB)

RAID Support

RAID 5, RAID 6, RAID 0

Form Factor

Rackmount

Dimensions

7.9 × 23 × 21.3 inches

View on Amazon: BUFFALO TeraStation 5420RN 16TB Rackmount NAS Affiliate link

The BUFFALO TeraStation 5420RN is a 4-bay rackmount NAS with 16TB of pre-installed storage. It features a native 10GbE port for fast transfers and 256-bit drive encryption. The system supports RAID 5 or 6 and includes snapshot capabilities for ransomware protection. This unit suits businesses needing secure, high-capacity data storage with hybrid cloud sync options for Dropbox and Azure.

Pros

• Native 10GbE port for high-speed file transfers
• 16TB capacity with 4x4TB drives included
• 256-bit drive encryption and two-factor authentication
• Snapshot feature for instant data recovery

Cons

• Closed system limits third-party app installation
• No mention of USB Type-C connectivity
• Heavier build at 27.2 pounds

Good fit if

• You need a 10GbE connection for fast data transfers
• You require built-in encryption and ransomware protection
• You want a rackmount unit with drives included

Skip if

• You prefer open platforms with extensive app ecosystems
• You need USB Type-C direct attachment
• You want a lightweight, portable storage solution

Verdict: BUFFALO TeraStation 5420RN 16TB Rackmount NAS fits businesses that prioritize security and speed over software flexibility. Its 10GbE port and encryption features make it a strong choice for protected data storage.

3 Best m.2 nvme

Asustor Lockerstor 4-Bay 10GbE NAS

Best for: users needing ECC RAM and 10GbE ports

Drive Bays

4 Bay

Network Connectivity

Dual 5GbE, Dual 10GbE

Processor

AMD Ryzen Quad-Core 2.3 GHz

RAM Capacity

16GB ECC DDR5

M.2 NVMe Slots

4 M.2 NVMe Slots

Included Storage

Diskless

View on Amazon: Asustor Lockerstor 4-Bay 10GbE NAS Affiliate link

This 4-bay NAS from Asustor uses an AMD Ryzen Quad-Core 2.3 GHz processor and 16GB of ECC DDR5 RAM. It includes four M.2 NVMe slots for fast caching or storage. The unit features dual 5GbE and dual 10GbE network ports. You get a diskless chassis measuring 12 by 10 by 13 inches. This setup suits users needing high memory and fast network speeds.

Pros

• 16GB ECC DDR5 RAM capacity
• Four M.2 NVMe slots
• Dual 10GbE network ports
• AMD Ryzen Quad-Core 2.3 GHz CPU

Cons

• Diskless design requires separate drive purchases
• Larger footprint than standard desktop NAS units
• No included storage media

Good fit if

• You need ECC memory for data integrity
• You require 10GbE network connectivity
• You want multiple NVMe drive options

Skip if

• You prefer a pre-configured storage solution
• You need a compact desktop form factor
• You only require 1GbE network speeds

Verdict: Asustor AS6804T 4-Bay NAS provides robust memory and networking for performance-focused setups. It fits users who prioritize ECC RAM and 10GbE speeds over plug-and-play convenience.

4 Also great

Synology 4-Bay Rackmount Expansion Unit

Best for: expanding Synology NAS storage capacity

Drive Bays

4-Bay

Included Storage

Diskless

Dimensions

17 × 11.4 × 1.73 inches

Weight

9.44 pounds

View on Amazon: Synology 4-Bay Rackmount Expansion Unit Affiliate link

The Synology RX418 is a 4-bay expansion unit designed to add storage to existing Synology NAS systems. It measures 17 by 11.4 by 1.73 inches and weighs 9.44 pounds. This diskless chassis supports online volume expansion and deep sleep mode for energy savings. You can manage it through Synology DiskStation Manager. It fits 2-post racks and mounts on walls.

Pros

• 4-bay capacity for additional drive space
• Supports online volume expansion
• Includes energy-saving deep sleep mode
• Fits 2-post and wall mount racks

Cons

• Diskless design requires existing Synology NAS
• No internal controller or power supply
• Limited to Synology ecosystem compatibility

Good fit if

• You need to expand storage for a Synology NAS
• You want to add 4 drive bays without buying a new system
• You have 2-post or wall mounting space available

Skip if

• You need a standalone NAS with its own controller
• You use a non-Synology NAS system
• You require a rackmount unit with built-in power and management

Verdict: Synology RX418 4-Bay Expansion Unit is a practical add-on for Synology users who need more drive bays. It fits well if you already own a Synology NAS and want to scale storage easily.

5 Best premium

G-Technology 32TB G-Speed Shuttle

Best for: Thunderbolt 3 video editing workflows

Drive Bays

4-Bay

Included Storage

32TB

RAID Support

0, 1, 5, 10

Hardware Interface

Thunderbolt

Dimensions

9.75 × 6.85 × 10.5 inches

Weight

16 pounds

View on Amazon: G-Technology 32TB G-Speed Shuttle Affiliate link

This is a 4-bay Thunderbolt 3 direct-attached storage unit with 32TB of capacity. It features built-in hardware RAID for data protection and a transportable design for mobile workflows. The device supports multi-stream 4K and 8K video editing. It connects via Thunderbolt interface and weighs 16 pounds. You should choose this if you need high-speed external storage for video production rather than a network-attached server.

Pros

• 32TB storage capacity
• Thunderbolt 3 interface
• Built-in hardware RAID 0, 1, 5, 10
• Transportable design

Cons

• No built-in network connectivity
• Requires host computer for operation
• Heavier than rackmount alternatives

Good fit if

• You need high-speed external storage for video editing
• You work with 4K or 8K multi-stream workflows
• You require Thunderbolt 3 connectivity

Skip if

• You need a standalone network-attached storage server
• You want to share files over a local network without a host
• You prefer a lightweight desktop drive

Verdict: G-Technology 32TB G-Speed Shuttle Thunderbolt 3 is a heavy, transportable 4-bay drive for video editors who need Thunderbolt 3 speed and hardware RAID on a single workstation.

6 Best budget

QNAP 4-Bay USB-C Hardware RAID Enclosure

Best for: expanding existing NAS capacity

Drive Bays

4-Bay

Included Storage

Diskless

RAID Support

RAID 0, 1, 5, JBOD

Dimensions

8.62 × 6.31 × 6.63 inches

Weight

4.08 pounds

View on Amazon: QNAP 4-Bay USB-C Hardware RAID Enclosure Affiliate link

The QNAP TR-004 is a direct-attached storage unit with four 3.5-inch SATA bays. It connects via USB Type-C for Windows, macOS, and Linux. Hardware RAID supports levels 0, 1, 5, JBOD, and individual disks. You can use it to expand NAS capacity or as external backup storage. It is a simple, diskless enclosure for adding drive space without network complexity.

Pros

• Four 3.5-inch SATA bays for high capacity
• Hardware RAID 0, 1, 5, JBOD support
• USB Type-C connection for fast data transfer
• Lockable drive bays for physical security

Cons

• Requires a host device; not a standalone NAS
• No local network connectivity or web interface
• Cannot run NAS applications or install software

Good fit if

• You need extra storage for an existing NAS
• You want hardware RAID without network setup
• You use Windows, macOS, or Linux

Skip if

• You need a standalone network-attached storage system
• You want to install apps or services
• You require direct IP network access

Verdict: The QNAP TR-004 4-Bay USB-C DAS is a practical expansion tool for users who already have a NAS and need more local storage space. It suits those who prefer simple hardware RAID over complex network configurations.

7 Also great

QNAP 4-Bay USB-C Direct Attached Storage

Best for: expanding single PC storage or NAS backup

Drive Bays

4-Bay

Included Storage

12TB

RAID Support

RAID 0, 1, 5, JBOD

View on Amazon: QNAP 4-Bay USB-C Direct Attached Storage Affiliate link

This is a direct-attached storage unit with four bays and pre-installed 12TB of Seagate IronWolf drives. It connects via USB Type-C to Windows, macOS, and Linux systems. The device supports RAID 0, 1, 5, and JBOD modes. You can use it as external backup storage or to expand the capacity of an existing QNAP NAS. It includes lockable drive bays for security.

Pros

• Pre-configured RAID 5 with 12TB capacity
• USB Type-C connection for broad OS support
• Lockable drive bays for physical security

Cons

• Limited to USB 3.2 Gen 1 speeds
• No internal network interface for direct NAS use
• No web management interface for remote configuration

Good fit if

• You need extra storage for a single computer
• You want to expand a QNAP NAS capacity
• You prefer plug-and-play RAID setup without configuration

Skip if

• You require high-speed 10GbE network connectivity
• You need a standalone network-attached storage server
• You want to manage storage remotely via the internet

Verdict: QNAP TR-004 4-Bay USB-C DAS is a simple expansion solution for users who need more local storage or backup space for their existing systems. It suits those who value pre-configured reliability over network flexibility.

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Frequently asked questions

See also

• wen 4 alternatives
• hlr 4 alternatives