Synology 4-Bay Expandable Rackmount NAS vs Synology 4-Bay Dual 2.5GbE NAS (2026): Key Differences
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You are comparing the synology 4 bay expandable rackmount NAS vs 4 bay dual 2 5gbe NAS to find the right storage for your needs. Both units are diskless, four-bay desktop solutions from Synology. The main difference lies in their design and networking. One model offers rackmount expandability and higher throughput, while the other provides dual 2.5GbE ports and a compact form factor. Your choice depends on your space and speed requirements.
Key differences
| Aspect | Synology 4-Bay Expandable Rackmount NAS | Synology 4-Bay Dual 2.5GbE NAS |
|---|---|---|
| Model | RS822+ | DS925+ |
| Network Ports | Four 1GbE ports | Dual 2.5GbE ports |
| Sequential Read/Write | Over 2,103/1,074 MB/s | Up to 522/565 MB/s |
| Expandability | Supports RX418 Expansion Unit | Not listed |
| Warranty | Not listed | 3-year limited hardware warranty |
| Weight | 18.7 pounds | 4.98 pounds |
Which one should you choose?
Choose Synology 4-Bay Expandable Rackmount NAS if
- You need to scale storage beyond four drives using an expansion unit
- You require higher sequential read and write throughput for large files
- You want to use four 1GbE ports for network failover or load balancing
Choose Synology 4-Bay Dual 2.5GbE NAS if
- You prefer faster 2.5GbE network connections for everyday transfers
- You want a lighter, more compact unit for a desk or small space
- You value the included 3-year limited hardware warranty
Verdict: The RS822+ is better for users who need high throughput and the ability to expand their storage capacity significantly. The DS925+ suits those who prioritize faster 2.5GbE networking and a lighter, more compact design. Choose based on whether you need expandability and raw speed or modern networking and portability.
Rackmount vs Desktop NAS Specs
Network connectivity
The Synology 4-Bay Expandable Rackmount NAS features four 1GbE ports, supporting network failover and load balancing. It also allows for optional 10/25GbE expansions to boost bandwidth further. In contrast, the Synology 4-Bay Dual 2.5GbE NAS provides dual 2.5GbE ports. These ports offer faster native transfer speeds and increased redundancy without needing extra expansion cards. If you need higher baseline speeds out of the box, the dual 2.5GbE setup is more efficient. However, the rackmount model offers greater flexibility for future high-speed upgrades.
Form factor and size
Physical dimensions vary significantly between these two models. The rackmount unit measures 17.2 inches wide, 10 inches high, and 19.3 inches long, weighing 18.7 pounds. It is designed for 19-inch server racks. The desktop model is much smaller, measuring 7.83 inches wide, 6.54 inches high, and 8.78 inches long, weighing only 4.98 pounds. This compact size makes it suitable for home offices or small workspaces where rack space is unavailable. You must choose based on your available physical space and mounting requirements.
Expandability
Storage expansion options differ between the two devices. The rackmount NAS can scale up to eight drives by connecting one Synology RX418 Expansion Unit. This allows you to double your drive capacity while maintaining the rackmount form factor. The desktop model does not list specific expansion unit compatibility in the provided data. It remains a fixed four-bay solution. If you anticipate needing more than four drives in the future, the rackmount model provides a clear path for growth through official expansion hardware.
Sequential throughput
Data transfer speeds are a key performance metric. The rackmount NAS supports over 2,103 MB/s sequential read and 1,074 MB/s sequential write throughput. This high performance supports stable transfers for large files and heavy workloads. The desktop model offers up to 522 MB/s read and 565 MB/s write throughput. While sufficient for many users, these numbers are significantly lower than the rackmount unit. If your workflow involves large video files or frequent bulk transfers, the rackmount model delivers superior raw performance.
Warranty coverage
Synology provides different warranty terms for these models. The desktop NAS is backed by a 3-year limited hardware warranty, offering longer protection for your investment. The rackmount model's warranty details are not listed in the provided data. Typically, enterprise-grade hardware may have different support tiers, but without specific data, you cannot confirm its terms. For peace of mind regarding hardware defects, the desktop model offers a clearly stated three-year coverage period right from the purchase.
Which NAS model fits your needs
You need rackmount expandability
This model supports expansion via an RX418 unit, allowing you to scale up to eight drives. It features four 1GbE ports for network failover and load balancing. You can also add optional 10/25GbE expansions for higher bandwidth. The sequential read and write speeds reach over 2,103 and 1,074 MB/s respectively, ensuring stable data transfers for larger setups.
You want faster native networking
This unit includes dual 2.5GbE ports, providing faster native network transfer speeds compared to standard gigabit connections. It offers sequential read and write throughput of up to 522 and 565 MB/s. The device is compact, measuring 7.83 by 6.54 by 8.78 inches and weighing just 4.98 pounds, making it easy to place on a desk or shelf.
You need a warranty
This model is backed by a three-year limited hardware warranty, giving you peace of mind regarding hardware reliability. It supports drives from Synology's official compatibility list. You get access to built-in file management, photo management, data protection, virtualization, and surveillance solutions. The compact design fits well in smaller spaces without requiring rack mounting.
The products compared
Synology 4-Bay Expandable Rackmount NAS
Best for: Expandable rackmount storage with redundancy
- Drive Bays
- 4-Bay
- Network Connectivity
- 4 x 1GbE
- RAM Capacity
- 32GB
- Included Storage
- Diskless
- Dimensions
- 19.3 × 17.2 × 10 inches
- Weight
- 18.7 pounds
View on Amazon: Synology 4-Bay Expandable Rackmount NAS Affiliate link
The Synology RS822+ is a 4-bay rackmount NAS designed for expandable storage. It offers over 2,103 MB/s sequential read throughput and includes four 1GbE ports for network failover. You can scale capacity by adding an RX418 expansion unit. This diskless unit supports optional SSD caching to boost random IOPS. It fits users needing robust, scalable network storage in a rack environment.
Pros
- Sequential read speeds exceed 2,103 MB/s
- Expands to 8 drives with RX418 unit
- Four 1GbE ports for failover and load balancing
- Supports optional SSD cache for IOPS
Cons
- Sold diskless with no included storage
- Base ports are limited to 1GbE
- Large 19.3-inch depth requires rack space
Good fit if
- You need expandable storage up to 8 drives
- You require network failover with multiple ports
- You have a 19-inch rack available
Skip if
- You need pre-loaded storage drives
- You require 10GbE connectivity out of the box
- You have limited rack space depth
Verdict: Synology RS822+ Rackmount NAS suits users who need scalable, high-throughput storage in a rack. It is ideal for those who plan to add expansion units and value network redundancy over immediate drive inclusion.
Synology 4-Bay Dual 2.5GbE NAS
Best for: Desktop users needing dual 2.5GbE speeds
- Drive Bays
- 4-Bay
- Network Connectivity
- Dual 2.5GbE
- Included Storage
- Diskless
- Dimensions
- 8.78 × 7.83 × 6.54 inches
- Weight
- 4.98 pounds
View on Amazon: Synology 4-Bay Dual 2.5GbE NAS Affiliate link
The Synology DS925+ is a 4-bay diskless NAS featuring dual 2.5GbE ports for fast, redundant networking. It delivers up to 565 MB/s sequential read and write speeds, supporting stable data transfers. You get built-in tools for file management, photo organization, virtualization, and surveillance. This unit is designed for users who need reliable performance and expandable storage without pre-installed drives.
Pros
- Dual 2.5GbE ports for fast network transfer speeds
- Up to 565 MB/s sequential read/write throughput
- Built-in file, photo, virtualization, and surveillance solutions
- Backed by a 3-year limited hardware warranty
Cons
- Sold diskless with no included storage drives
- Not a rackmount chassis for server rooms
- No mention of USB expansion ports in specs
Good fit if
- You need fast dual 2.5GbE network connectivity
- You want a compact 4-bay desktop NAS
- You prefer to choose your own hard drives
Skip if
- You require a rackmount form factor
- You need a NAS with pre-installed drives
- You want 10GbE network ports
Verdict: Synology DS925+ 4-Bay NAS is a solid desktop choice for users who value dual 2.5GbE speeds and flexible storage expansion over rackmount mounting options.
Specifications side by side
| Spec | Synology 4-Bay Expandable Rackmount NAS | Synology 4-Bay Dual 2.5GbE NAS |
|---|---|---|
| Drive Bays | 4-Bay | 4-Bay |
| Network Connectivity | 4 x 1GbE | Dual 2.5GbE |
| RAM Capacity | 32GB | not stated |
| Included Storage | Diskless | Diskless |
| Number of Bays | 4-Bay | 4-Bay |
| Dimensions | 19.3 × 17.2 × 10 inches | 8.78 × 7.83 × 6.54 inches |
| Weight | 18.7 pounds | 4.98 pounds |
| Size | RS822+ | 166 mm x 199 mm x 223 mm |
| Color | Not Available | Black |
| Model | RS822+ | DS925+ |
Frequently asked questions
Can I mount the Synology RS822+ in a standard server rack?
Yes, the Synology RS822+ is designed for rackmount use. It measures 17.2 inches in width and 10 inches in height. These dimensions allow it to fit into standard 19-inch server racks. This makes it suitable for data centers or dedicated server rooms where space efficiency matters.
What is the weight difference between the RS822+ and DS925+?
The RS822+ weighs 18.7 pounds, while the DS925+ weighs 4.98 pounds. The rackmount model is significantly heavier due to its metal chassis and rackmount hardware. The desktop DS925+ is much lighter, making it easier to place on a desk or shelf without heavy mounting brackets.
Does the Synology DS925+ support rackmount installation?
No, the DS925+ is a desktop unit. It measures 8.78 inches in length, 7.83 inches in width, and 6.54 inches in height. It is designed to sit on a flat surface. It does not include the hardware or form factor required for rackmount installation.
How do I expand storage on the Synology RS822+?
You can expand storage by adding an RX418 expansion unit. This allows you to scale up to eight drives total. The RS822+ is built for scalability, making it ideal for users who anticipate needing more capacity in the future without replacing the main NAS unit.
Which model has faster native network speeds?
The DS925+ has faster native network speeds. It features dual 2.5GbE ports. The RS822+ features four 1GbE ports. While the RS822+ supports optional 10/25GbE expansions, the DS925+ delivers higher throughput out of the box without requiring additional hardware upgrades.
Can I use the RS822+ for network load balancing?
Yes, the RS822+ supports network load balancing. It includes four 1GbE ports that can be configured for this purpose. This setup helps distribute network traffic across multiple connections. It also supports network failover to maintain connectivity if one link fails.