Best Synology Hard Drive Enclosures: 15 Models Compared
As an Amazon Associate we earn from qualifying purchases. Links on this page are affiliate links.
Finding the right synology hard drive enclosure depends on whether you need a standalone network server or an expansion unit for existing hardware. Synology offers desktop towers and rackmount units ranging from 2-bay configurations to 12-bay systems in black and white finishes.
The Synology RackStation Storage Expansion Enclosure earns the top spot as it is best for expanding compatible Synology RackStation capacity without downtime. We compared 15 models using strictly the specifications published on their product listings to help you find the right hardware.
Quick picks
Our 15 picks
Synology RackStation Storage Expansion Enclosure
Best for: expanding compatible Synology RackStation capacity without downtime
- Dimensions
- 25.4 × 17 × 3.46 inches
- Weight
- 28 pounds
View on Amazon: Synology RackStation Storage Expansion Enclosure
The Synology RackStation Storage Expansion Enclosure expands your existing RackStation setup without downtime. It measures 3.46 inches high, 16.95 inches wide, and 25.35 inches deep, with a total weight of 28 pounds. You control the diskless unit directly through Synology DiskStation Manager (DSM). It provides plug-and-use connectivity and supports on-the-fly online volume expansion. This enclosure suits you if you need seamless rackmount capacity upgrades managed under your current DSM interface.
Pros
- Managed directly from Synology DiskStation Manager (DSM)
- Supports online volume expansion on the fly
- Plug-n-use design for storage space upgrades
- Chassis dimensions of 3.46 by 16.95 by 25.35 inches
Cons
- Ships diskless without pre-installed drives
- Weighs 28 pounds before drives are installed
- Deep 25.35-inch chassis requires substantial rack clearance
Good fit if
- You need on-the-fly storage expansion managed through Synology DSM.
- You have a compatible Synology RackStation system.
- You have server rack space that accommodates a 25.35-inch chassis depth.
Skip if
- You need a standalone NAS unit rather than an expansion enclosure.
- You need hard drives included in the initial purchase.
- You operate in a shallow rack unable to house a 25.35-inch unit.
Verdict: Synology RackStation Storage Expansion Enclosure delivers direct online capacity expansion managed entirely through Synology DiskStation Manager. It provides a straightforward upgrade path for expanding an existing rack setup.
Synology 2U Rackmount Redundant Power Expansion Unit
Best for: rack deployments requiring redundant power supply protection
- Dimensions
- 27.4 × 17 × 3.46 inches
- Weight
- 29.5 pounds
View on Amazon: Synology 2U Rackmount Redundant Power Expansion Unit
This 2U rackmount expansion enclosure adds storage space to your Synology RackStation setup through a plug-and-use connection. It features redundant power supplies to keep drives running without interruption and supports online volume expansion directly inside Synology DiskStation Manager (DSM). Measuring 27.4 inches long and weighing 29.54 pounds, it suits rack environments where continuous uptime and managed expansion matter most for your storage infrastructure.
Pros
- Redundant power supplies maintain uptime during power interruptions
- Supports online volume expansion on the fly
- Managed directly through Synology DiskStation Manager (DSM)
- Plug-and-use design allows direct storage expansion
Cons
- Ships diskless without pre-installed storage drives
- Chassis length of 27.4 inches requires a deep server rack
- Requires a compatible Synology RackStation base unit to operate
Good fit if
- You need redundant power supplies to protect against power feed loss.
- You want to expand volume capacity on the fly using Synology DSM.
- You have server rack space that accommodates a 2U, 27.4-inch deep chassis.
Skip if
- You need a standalone NAS unit rather than a RackStation expansion enclosure.
- You use a shallow server rack that cannot fit a 27.4-inch chassis depth.
Verdict: Synology 2U Rackmount Redundant Power Expansion Unit delivers uninterrupted storage expansion for compatible RackStation systems needing hardware power redundancy. It enables seamless volume scaling managed centrally via DiskStation Manager.
Synology 4-Bay Rackmount Expansion Unit
Best for: shallow-depth 2-post rack storage expansion
- Number of Bays
- 4bay
- Dimensions
- 17 × 11.4 × 1.73 inches
- Weight
- 9.44 pounds
This 4-bay expansion enclosure adds storage capacity to your Synology deployment using online volume expansion. Its 12-inch depth fits compact 2-post and wall-mount racks, measuring 1.73 inches high and weighing 9.44 pounds. You manage drives directly through Synology DiskStation Manager, and the unit supports an energy-saving deep sleep mode. It suits you if you need extra drive capacity in shallow rack cabinets.
Pros
- 12-inch depth fits 2-post and wall-mount racks
- Supports online volume expansion via DiskStation Manager
- Energy-saving deep sleep mode
- Compact 1.73-inch height
Cons
- Provides only 4 drive bays
- Ships diskless with no pre-installed drives
- Rackmount form factor not built for desktop use
Good fit if
- You need a compact 4-bay expansion for a 2-post or wall-mount rack.
- You want online volume expansion managed via Synology DiskStation Manager.
- You want an expansion enclosure featuring an energy-saving deep sleep mode.
Skip if
- You need more than four drive bays in a single enclosure.
- You want a desktop tower unit rather than a rackmount chassis.
- You need an enclosure that includes pre-installed storage drives.
Verdict: Synology 4-Bay Shallow-Depth Expansion Unit delivers straightforward four-bay storage growth for shallow 2-post and wall-mount rack installations. It integrates directly into DiskStation Manager with plug-and-play setup and deep sleep support.
Synology 4-Bay Intel Quad-Core NAS
Best for: expandable four-bay storage with SSD caching
- Number of Bays
- 4-bay
- Processor Cores
- quad-core
- RAM Capacity
- 4 GB DDR4
- Dimensions
- 8.78 × 7.83 × 6.54 inches
- Weight
- 4.94 pounds
This diskless 4-bay enclosure provides central network storage powered by an Intel quad-core processor with AES-NI hardware encryption. It features 4 GB of DDR4 memory and dual M.2 2280 NVMe SSD slots for cache acceleration without occupying standard drive bays. You can scale capacity up to nine drives using a DX517 expansion unit, delivering sequential read and write speeds over 225 MB/s.
Pros
- Two built-in M.2 2280 NVMe SSD slots for cache acceleration
- Intel quad-core processor with AES-NI hardware encryption
- Scalable up to 9 drives with Synology DX517
- 4 GB DDR4 memory expandable up to 8 GB
Cons
- Ships diskless without pre-installed storage drives
- Maximum memory expansion is capped at 8 GB
- Includes only two default camera licenses
Good fit if
- You want NVMe SSD caching without using any of the main drive bays.
- You plan to start with four drives and expand up to nine drives later.
Skip if
- You need more than 8 GB of total system RAM.
- You require an enclosure that comes pre-loaded with hard drives.
Verdict: Synology 4-Bay NAS with Dual NVMe Slots delivers reliable multi-drive storage with dedicated slots for high-speed SSD caching. It offers solid quad-core performance with room to expand up to nine bays.
Synology 8-Bay Redundant Power RackStation
Best for: Compact racks needing high-availability multi-user storage
- Number of Bays
- 8 bay
- RAM Capacity
- 4GB RAM
- Dimensions
- 22.5 × 20.8 × 8.5 inches
This 8-bay rackmount enclosure gives you centralized network storage designed for server racks with a 399 mm depth. It includes 4GB of RAM and delivers speeds up to 2,315 MB/s read and 1,147 MB/s write. You can expand networking through an optional PCIe card or pair two enclosures for Synology High Availability failover clusters. It suits multi-user business environments needing compact rack placement and dual power protection.
Pros
- Short chassis depth of 399 mm fits compact rack setups
- Delivers up to 2,315 MB/s read and 1,147 MB/s write performance
- Supports PCIe network cards for SFP+ or RJ-45 upgrades
- Supports Synology High Availability for cluster failover
Cons
- Comes diskless without hard drives included
- Ships with 4GB RAM out of the box
- Requires a separate PCIe card for upgraded network speeds
Good fit if
- You need an 8-bay rackmount enclosure with a compact 399 mm chassis depth.
- You want dual-unit high-availability clustering for failover protection.
- You plan to add high-speed SFP+ or RJ-45 networking via PCIe expansion.
Skip if
- You need pre-installed hard drives ready to deploy immediately.
- You want a desktop form factor instead of a rackmount unit.
Verdict: Synology 8-Bay Redundant Power RackStation delivers high-speed multi-user throughput in a short-depth rack design with PCIe expansion.
Synology 12-Bay DiskStation Expansion Unit
Best for: large-scale DiskStation capacity expansion
- Number of Bays
- 12 Bay
- Dimensions
- 18.5 × 17.1 × 16.5 inches
- Weight
- 19.9 pounds
This 12-bay expansion unit connects to your compatible Synology DiskStation through a plug-and-play setup. It supports Synology HAT5300 SATA hard drives, allowing you to add 12 extra drives to your existing array without buying a standalone NAS. Weighing 19.9 pounds with dimensions of 270 mm by 300 mm by 340 mm, it suits your setup if you need massive local capacity backed by a 5-year limited warranty.
Pros
- Adds 12 drive bays to a compatible DiskStation
- Plug-and-play design for direct storage expansion
- Backed by a 5-year limited warranty
- Verified compatibility with Synology HAT5300 SATA drives
Cons
- Ships diskless without pre-installed storage
- Requires a separate host DiskStation to function
- Substantial empty weight of roughly 19.9 pounds
Good fit if
- You already run a compatible Synology DiskStation and need 12 extra bays.
- You plan to populate your storage with Synology HAT5300 SATA hard drives.
- You want an expansion enclosure covered by a 5-year warranty.
Skip if
- You need an independent NAS with an integrated processor and operating system.
- You want a fully populated storage unit that includes drives in the box.
Verdict: Synology 12-Bay DiskStation Expansion Unit adds 12 plug-and-play bays to your existing DiskStation setup. It delivers massive SATA drive expansion backed by a 5-year limited warranty.
Synology 12-Bay Quad-Core NAS
Best for: high-capacity scalable centralized storage
- Number of Bays
- 12-bay
- Processor Cores
- Quad Core
- RAM Capacity
- 4GB DDR4
- Dimensions
- 18.5 × 17 × 16.5 inches
- Weight
- 20.9 pounds
This diskless 12-bay desktop unit gives you high-capacity network storage powered by a quad-core processor and 4GB of DDR4 memory. It reaches sequential speeds up to 2,201 MB/s read and 1,383 MB/s write. You can expand capacity to 24 drive bays with an optional DX1222 expansion unit or upgrade memory up to 32 GB. It suits teams needing massive local file capacity and fast sequential read throughput.
Pros
- Delivers up to 2,201 MB/s read and 1,383 MB/s write speeds
- Scales up to 24 drive bays with DX1222 expansion unit
- Supports memory expansion up to 32 GB
- Supports 10/25GbE network cards and NVMe SSD cache upgrades
- Backing includes a 3-year warranty
Cons
- Base configuration includes only 4GB of memory
- Requires separate purchase of hard drives
- Large desktop footprint weighing over 20 pounds empty
Good fit if
- You need 12 native drive bays with expansion up to 24 bays.
- You require sequential read throughput reaching up to 2,201 MB/s.
- You plan to add high-speed 10/25GbE networking or NVMe SSD cache.
Skip if
- You want a compact enclosure for tight desktop spaces.
- You need pre-installed hard drives included in the box.
- You require more than 4GB of memory out of the box without upgrading.
Verdict: Synology 12-Bay Quad-Core NAS delivers scalable multi-drive storage with high sequential throughput and extensive upgrade options. It handles large-capacity centralized storage workloads reliably under its 3-year warranty.
Synology 12-Bay Xeon Desktop Enclosure
Best for: virtualization and high-capacity multi-drive storage
- Number of Bays
- 12 Bay
- Processor
- Intel Xeon
- Processor Cores
- 6-core
- RAM Capacity
- 16GB RAM
- Dimensions
- 17 × 18.3 × 17 inches
- Weight
- 21.6 pounds
This 12-bay desktop storage enclosure provides centralized network storage powered by a 6-core Intel Xeon processor and 16 GB of memory. It supports up to 48 GB of RAM and expands up to 36 drive bays using two 12-bay expansion units. You also get support for 10/25GbE networking, Fibre Channel, and NVMe SSD caching. It suits you if you host virtual machines, video management, or extensive business backups.
Pros
- 6-core Intel Xeon processor
- 12 internal drive bays expandable up to 36 bays
- 16 GB RAM installed, expandable up to 48 GB
- Supports 10/25GbE networking and NVMe SSD caching
- 5-year manufacturer warranty
Cons
- Large footprint measuring 17 inches high and 18.25 inches wide
- Chassis weighs 21.6 pounds before adding drives
- Scaling past 12 bays requires purchasing external expansion units
Good fit if
- You need 12 drive bays with expansion up to 36 bays for massive capacity.
- You require a 6-core Xeon processor and expandable RAM for virtual machines or video management.
- You plan to implement high-speed 10/25GbE network connections or NVMe caching.
Skip if
- You have limited workspace for a unit that measures 17 inches tall and deep.
- You only require a simple two-bay or four-bay enclosure for basic data storage.
Verdict: Synology 12-Bay Xeon Desktop Enclosure provides high computational power and extensive scaling through its 6-core Xeon processor and 12 internal drive bays. It serves demanding data operations that require enterprise-level expansion in a tower format.
Synology 2-Bay 2GB RAM NAS Hub
Best for: compact two-bay home and office backup
- Number of Bays
- 2-Bay
- RAM Capacity
- 2GB RAM
- Dimensions
- 6.5 × 4.25 × 9.17 inches
- Weight
- 2.82 pounds
This two-bay desktop enclosure operates with 2GB of DDR4 memory and comes diskless. You can connect IP cameras for automated surveillance, schedule automated data backups from computers and mobile devices, and sync files across teams. Its compact chassis measures 4.25 inches wide and weighs 2.82 pounds. It suits home offices or small workspaces where you need centralized network storage, multi-device backup protection, and local file ownership without multi-bay expansion overhead.
Pros
- Two drive bays for centralized data consolidation
- 2GB of DDR4 system memory
- Built-in IP camera surveillance with motion alerts and recording schedules
- Automated backup support for Macs, PCs, and mobile devices
- Two-year manufacturer hardware warranty
Cons
- Comes diskless with no hard drives included
- Limited to two drive bays
- Fixed 2GB RAM configuration
Good fit if
- You want automated backup across computers and mobile hardware.
- You need a compact two-bay network enclosure for home or office file sync.
- You plan to set up IP camera recording and remote monitoring.
Skip if
- You require more than two drive bays for large-scale storage.
- You need an enclosure that includes pre-installed hard drives.
- You need more than 2GB of system memory for heavy workloads.
Verdict: Synology 2-Bay 2GB RAM NAS Hub delivers centralized data backups, file synchronization, and IP camera monitoring in a compact two-bay chassis. It offers reliable local network storage backed by a two-year warranty.
Synology 12-Bay Redundant Power Expansion Unit
Best for: high-availability rack storage expansion
- Number of Bays
- 12-Bay
- Dimensions
- 32.7 × 25.7 × 8.27 inches
- Weight
- 38.5 pounds
View on Amazon: Synology 12-Bay Redundant Power Expansion Unit
This Synology 12-bay expansion unit connects to your compatible deployment to expand storage via Synology DSM management tools. It accepts up to twelve 2.5-inch or 3.5-inch SATA hard drives or solid-state drives. Built-in redundant power supplies protect against power hardware outages. Measuring 16.9 by 27.2 by 3.5 inches and weighing 38.45 pounds, it suits enterprise server racks that require uninterrupted uptime and large-scale plug-and-play capacity addition.
Pros
- Accommodates twelve 2.5-inch or 3.5-inch SATA HDDs or SSDs
- Integrated redundant power supply prevents single points of failure
- Five-year limited warranty coverage
- Managed directly through unified Synology DSM tools
Cons
- Functions only as an expansion unit, not a standalone NAS
- Comes diskless with drives sold separately
- Deep 27.2-inch chassis and 38.45-pound weight require ample rack space
Good fit if
- You need to add twelve SATA drive bays to an existing Synology system.
- You require dual redundant power supplies for continuous uptime.
- You have server rack space for a 27.2-inch deep enclosure.
Skip if
- You need an independent, standalone NAS device.
- You do not have a compatible Synology host system running DSM.
- You lack the physical rack space for a 38.45-pound chassis.
Verdict: Synology 12-Bay Redundant Power Expansion Unit delivers scalable twelve-bay SATA capacity with critical hardware failover via dual power supplies. It serves enterprise setups expanding their existing Synology storage environment without service interruption.
Synology 5-Bay SATA Expansion Unit
Best for: expanding compatible DiskStation storage with five drives
- Number of Bays
- 5-Bay
- Dimensions
- 8.78 × 9.06 × 6.54 inches
- Weight
- 5.42 pounds
This diskless expansion unit adds five additional 3.5-inch or 2.5-inch SATA hard drive or solid-state drive bays to your existing DiskStation setup. It measures 9.06 inches wide by 6.54 inches high by 8.78 inches long and weighs 5.42 pounds. Managed directly through Synology DSM unified tools, it suits you if your current storage is full and you need plug-and-play, hot-swappable drive expansion backed by a three-year limited hardware warranty.
Pros
- Adds 5 bays for 3.5-inch or 2.5-inch SATA HDDs or SSDs
- Supports hot-swapping drives with plug-and-play setup
- Configured directly through Synology DSM unified tools
- Backed by a 3-year limited hardware warranty
Cons
- Requires an existing compatible DiskStation to operate
- Drive support is restricted to the official compatibility list
- Ships diskless with no pre-installed storage drives
Good fit if
- You need to add up to five SATA drives to an existing DiskStation.
- You want hot-swappable bays that configure through Synology DSM tools.
- You use drives found on the model's official compatibility list.
Skip if
- You need an independent, standalone NAS rather than an expansion unit.
- You plan to install drives not listed on the official compatibility list.
Verdict: Synology 5-Bay Hot-Swap Expansion Unit expands your existing DiskStation capacity with five hot-swappable SATA drive bays. It integrates directly into Synology DSM tools and carries a 3-year limited hardware warranty.
Synology 2-Bay Desktop NAS Enclosure
Best for: compact home backups and IP camera recording
- Number of Bays
- 2-Bay
- Dimensions
- 6.5 × 3.94 × 8.9 inches
- Weight
- 1.92 pounds
This Synology 2-Bay Desktop NAS Enclosure is a compact, two-bay diskless storage unit designed for personal data management. Measuring 3.94 by 8.9 by 6.5 inches and weighing under two pounds, it houses two drives for cross-platform file sharing and automated backups across Mac, PC, and mobile platforms. It also supports 24/7 IP camera recording for home security. This enclosure suits you if you need a straightforward, small-footprint private cloud backed by a two-year warranty.
Pros
- Two drive bays in a compact 3.94 x 8.9 x 6.5-inch chassis
- Automated backup support for Mac, PC, and mobile devices
- Integrated 24/7 IP camera recording and remote monitoring support
- Lightweight build weighing approximately 1.92 pounds
- Two-year hardware warranty coverage
Cons
- Ships diskless without pre-installed storage drives
- Restricted to two drive bays without built-in expansion bays
Good fit if
- You need automated backups across Mac, PC, and mobile devices.
- You want an enclosure capable of 24/7 IP camera recording.
- You require a compact desktop footprint under four inches wide.
Skip if
- You need more than two storage bays for high-capacity scaling.
- You want drives pre-installed inside the enclosure.
Verdict: Synology 2-Bay Desktop NAS Enclosure delivers practical two-bay capacity with multi-device automated backup and IP camera monitoring support. It provides an efficient entry point for running a private cloud within a compact footprint.
Synology 5-Bay 10GbE Desktop NAS
Best for: high-speed 10GbE video editing workflows
- Number of Bays
- 5-Bay
- Network Connectivity
- 10GbE
- Dimensions
- 8.78 × 9.06 × 6.54 inches
- Weight
- 5.89 pounds
This Synology 5-bay desktop enclosure is built for high-throughput network storage. It supports 10GbE network connectivity and transfers up to 1,181 MB/s, allowing you to edit 4K or 8K video directly across the network. The system holds up to 100TB internally and scales to 300TB with DX525 expansion units. It suits you if you need fast multi-user collaboration and high-capacity storage for media production.
Pros
- Delivers transfer speeds up to 1,181 MB/s for 4K and 8K workflows
- Supports 10GbE network connectivity for multi-user editing
- Expands from 100TB base storage to 300TB with DX525 units
- Backed by a 3-year warranty with enterprise support options
Cons
- Internal capacity stops at 100TB without external DX525 hardware
- Reaches 300TB maximum capacity only through add-on expansion units
Good fit if
- You need network throughput reaching 1,181 MB/s for high-resolution video editing.
- You require 10GbE network connectivity for simultaneous multi-user workflows.
- You plan to scale your media storage from 100TB up to 300TB over time.
Skip if
- You need more than 100TB of storage without adding external DX525 units.
- You do not require 10GbE network speeds for your daily storage tasks.
Verdict: Synology 5-Bay 10GbE Desktop NAS provides fast 1,181 MB/s throughput and 10GbE connectivity for collaborative video workflows. It is a capable 5-bay platform that scales up to 300TB as your storage demands increase.
Synology 8-Bay Expandable NAS Enclosure
Best for: Multi-user teams needing expandable high-speed storage
- Number of Bays
- 8-Bay
- Dimensions
- 9.57 × 13.5 × 6.54 inches
- Weight
- 13.2 pounds
The Synology 8-Bay Expandable NAS Enclosure is an 8-bay desktop unit built for data-heavy environments. It offers an initial capacity up to 160TB that scales to 360TB with expansion units, alongside transfer speeds up to 2,239 MB/s. You can add 10GbE or 25GbE network cards for demanding workflows. This enclosure fits creative groups running multi-user 4K or 8K video editing, virtual machines, and high-availability clustered storage across shared workspaces.
Pros
- Supports up to 8 drives with expansion scaling to 360TB
- Delivers transfer rates up to 2,239 MB/s
- Accepts optional 10GbE and 25GbE network upgrade cards
- Comes with a 3-year warranty and enterprise support
Cons
- Requires separate add-on cards to achieve 10GbE or 25GbE speeds
- Needs external expansion units to reach the full 360TB capacity
- Weighs 13.2 pounds before drives are installed
Good fit if
- You need an 8-bay system that can scale up to 360TB.
- You require transfer speeds up to 2,239 MB/s for multi-user video editing.
- You want the option to upgrade to 10GbE or 25GbE networking.
Skip if
- You need out-of-the-box 10GbE or 25GbE ports without buying extra cards.
- You want a compact enclosure smaller than 13.5 inches wide.
Verdict: Synology 8-Bay Expandable NAS Enclosure delivers 8 bays of storage, speeds up to 2,239 MB/s, and networking upgrades up to 25GbE. It offers substantial expansion capacity up to 360TB for demanding team environments.
Synology 2-Bay Expandable Desktop NAS
Best for: home users and small businesses
- Number of Bays
- 2-Bay
- Intended Use
- Home Users
- Dimensions
- 8.78 × 4.17 × 6.54 inches
- Weight
- 3.33 pounds
The Synology DS725+ is a 2-bay NAS designed for home users and small businesses. It supports expansion to 140TB via a DX525 unit. The system handles up to 30 IP cameras with advanced analytics. You get multi-layered data protection through RAID and snapshots. It includes a 3-year warranty for reliable hardware. This compact unit fits well in home offices or small workspaces.
Pros
- 2-bay capacity with expansion to 140TB
- Supports up to 30 IP cameras
- Includes 3-year warranty
- Advanced data protection with RAID and snapshots
Cons
- Only 2 drive bays
- No mention of RAM or CPU specs
- Diskless design requires separate drive purchase
Good fit if
- You need a compact NAS for home use
- You want to expand storage up to 140TB
- You require surveillance for up to 30 cameras
Skip if
- You need more than 2 bays without expansion
- You require enterprise-grade redundant power
- You prefer a pre-loaded drive configuration
Verdict: Synology DS725+ 2-Bay NAS is a compact, expandable solution for home users and small businesses needing surveillance and scalable storage. It fits those prioritizing data protection and camera management in a small footprint.
Specifications side by side
| Spec | Synology RackStation Storage Expansion Enclosure | Synology 2U Rackmount Redundant Power Expansion Unit | Synology 4-Bay Rackmount Expansion Unit | Synology 4-Bay Intel Quad-Core NAS | Synology 8-Bay Redundant Power RackStation | Synology 12-Bay DiskStation Expansion Unit | Synology 12-Bay Quad-Core NAS | Synology 12-Bay Xeon Desktop Enclosure | Synology 2-Bay 2GB RAM NAS Hub | Synology 12-Bay Redundant Power Expansion Unit | Synology 5-Bay SATA Expansion Unit | Synology 2-Bay Desktop NAS Enclosure | Synology 5-Bay 10GbE Desktop NAS | Synology 8-Bay Expandable NAS Enclosure | Synology 2-Bay Expandable Desktop NAS |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Number of Bays | not specified | not specified | 4bay | 4-bay | 8 bay | 12 Bay | 12-bay | 12 Bay | 2-Bay | 12-Bay | 5-Bay | 2-Bay | 5-Bay | 8-Bay | 2-Bay |
| Processor | not specified | not specified | not specified | not specified | not specified | not specified | not specified | Intel Xeon | not specified | not specified | not specified | not specified | not specified | not specified | not specified |
| Processor Cores | not specified | not specified | not specified | quad-core | not specified | not specified | Quad Core | 6-core | not specified | not specified | not specified | not specified | not specified | not specified | not specified |
| RAM Capacity | not specified | not specified | not specified | 4 GB DDR4 | not specified | not specified | 4GB DDR4 | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified |
| Network Connectivity | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | 10GbE | not specified | not specified |
| Intended Use | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | not specified | Home Users |
| Dimensions | 25.4 × 17 × 3.46 inches | 27.4 × 17 × 3.46 inches | 17 × 11.4 × 1.73 inches | 8.78 × 7.83 × 6.54 inches | 22.5 × 20.8 × 8.5 inches | 18.5 × 17.1 × 16.5 inches | 18.5 × 17 × 16.5 inches | 17 × 18.3 × 17 inches | 6.5 × 4.25 × 9.17 inches | 32.7 × 25.7 × 8.27 inches | 8.78 × 9.06 × 6.54 inches | 6.5 × 3.94 × 8.9 inches | 8.78 × 9.06 × 6.54 inches | 9.57 × 13.5 × 6.54 inches | 8.78 × 4.17 × 6.54 inches |
| Weight | 28 pounds | 29.5 pounds | 9.44 pounds | 4.94 pounds | not specified | 19.9 pounds | 20.9 pounds | 21.6 pounds | 2.82 pounds | 38.5 pounds | 5.42 pounds | 1.92 pounds | 5.89 pounds | 13.2 pounds | 3.33 pounds |
| Size | 88 mm x 482 mm x 696 mm | 2U x 24" x 36" | 44 mm x 480 mm x 325 mm | DS920+ | RS1221RP+ | 270 mm x 300 mm x 340 mm | 12-bay; 4GB DDR4 | DS3622xs+ | DS223 | 16.9" x 27.2" x 3.5" | 166 mm x 230 mm x 223 mm | 2-bay | 166 mm x 230 mm x 223 mm | 166 mm x 343 mm x 243 mm | 166 mm x 106 mm x 223 mm |
| Color | Black | Black | black | Black | Black | Black | Black | Black | Black | Black | Black | White | Black | Black | Black |
| Model | RX1217 | RX1217RP | RX418 | DS920+ | RS1221RP+ | DX1215II | DS2422+ | DS3622xs+ | DS223 | RX1223RP | DX525 | DS223j | DS1525+ | DS1825+ | DS725+ |
Choosing the Right Synology Enclosure
Desktop NAS towers split between entry-level models and high-capacity multi-bay systems. If you need local backups for a home or small office, two-bay to four-bay units like the DS223j and DS423 provide 2GB of RAM with low power footprints. For virtualization and enterprise hosting, larger eight-bay to twelve-bay enclosures like the DS3622xs+ offer 16GB of RAM and multi-core processing power.
If you already operate a host server, expansion enclosures add drive bays without extra network management. Models like the RX1217 scale capacity across rackmount deployments. Choose a standalone desktop enclosure if you need an independent server, or select an expansion chassis if your existing storage array requires more drive bays.
Where Synology Enclosures Fit
Synology covers setups from compact 2-bay desktop towers to 12-bay 2U rackmount enclosures. Unit weights scale from the 1.9-pound DS223j to the 38.45-pound RX1223RP. Color options include only standard black and white finishes, with no case lighting options.
The lineup leaves clear gaps if you need alternative drive counts. You will find no single-bay units, nor any 6-bay or 10-bay enclosures. Network connectivity across these models is strictly wired Ethernet reaching up to 25GbE, leaving out built-in Wi-Fi connectivity entirely.
You can also review the best MAIWO SSD enclosures to compare other storage options.
How to Choose a Synology Enclosure
-
Matching Bay Count to Growth
Calculate your raw storage requirements plus projected growth before selecting bay counts. Units with two or four bays handle basic backup tasks, but limit future expansion. Choosing an enclosure with eight or twelve bays allows broader RAID protection modes like dual-disk redundancy. The eight-bay DS1825+ provides sufficient drive channels to expand raw storage without swapping active disks for larger sizes later. Check whether the model supports external expansion units if you anticipate exceeding internal bay capacity over time.
-
Evaluating System Memory Requirements
Evaluate system memory based on planned software tasks rather than simple file storage. Base tasks like file backups run efficiently on 2GB of RAM. Multi-user file sharing, Docker containers, and high-frequency indexing demand at least 4GB of memory. Intensive environments that run local virtual machines require 16GB or higher to prevent performance bottlenecks. For heavy virtualization deployments, the DS3622xs+ includes 16GB of system memory out of the box. Verify memory expandability if your workload involves concurrent users or memory-heavy background services.
-
Checking Network Interface Speeds
Match network port specifications to your workflow transfer requirements. Standard Gigabit Ethernet ports limit sequential transfers to approximately 110 megabytes per second, creating a bottleneck during multi-user file access. High-bandwidth tasks like multi-stream 4K video editing benefit directly from 10GbE interfaces. The DS1525+ features built-in 10GbE connectivity that reaches transfer rates up to 1,181 megabytes per second over compatible network infrastructure. Confirm whether your client machines and local network switches support multi-gigabit connections before prioritizing high-speed network ports on your enclosure.
-
Assessing Redundant Power Needs
Look for redundant power supply units if continuous operational uptime is essential for your storage deployment. Standard desktop models rely on a single power adapter, meaning an internal power component failure causes immediate server downtime. Redundant power models include dual power modules connected to separate power sources, allowing continuous system operation if one feed fails. The rackmount RX1217RP provides dual power supplies to protect enterprise data environments against hardware power faults. Choose redundant power configurations for production storage setups that cannot tolerate unexpected maintenance interruptions.
-
Utilizing Dedicated NVMe Caching
Check for dedicated NVMe slots if your workload involves frequent random read and write operations. Enabling solid-state caching significantly accelerates file indexing, multi-user database queries, and small file transfers. Built-in M.2 slots provide high caching throughput without occupying standard 3.5-inch hard drive bays. The DS920+ integrates dual NVMe slots, letting you configure an SSD read-write cache while preserving all four primary drive bays for bulk capacity. Opt for dedicated caching bays if you host multi-user applications or virtual containers where mechanical drive latency creates operational delays.
-
Verifying Rack Chassis Depth
Measure rack cabinet depth before choosing rackmount storage hardware. Standard enterprise rack enclosures often exceed 25 inches in length and require full-depth four-post server cabinets. If you maintain compact wall-mount cabinets or shallow two-post racks, deep units will not fit. The shallow-depth RX418 measures 325 millimeters in depth, fitting easily inside space-constrained telecom frames. Verify both the chassis dimensions and necessary rear cable clearance before ordering rackmount equipment.
Frequently asked questions
Can you use a Synology expansion unit as a standalone NAS?
No. Expansion units like the DX525, DX1215II, or RX1217 lack standalone CPU and memory systems. They require a connection to a host DiskStation or RackStation system running Synology DiskStation Manager. You manage the additional bays directly through the host operating system to enlarge volumes or create independent storage pools.
What is the difference between Synology RP and non-RP models?
RP designations indicate redundant power supply hardware inside the chassis. Models such as the RX1217RP, RS1221RP+, and RX1223RP include dual power modules that protect against electrical supply interruptions. If one power source fails, the secondary supply maintains uninterrupted storage operation. Standard models rely on a single power connection without built-in hardware power failover.
Which Synology enclosures support high-speed networking upgrades like 10GbE or 25GbE?
Several multi-bay enclosures include high-speed networking or expansion slots for network cards. For example, the DS1525+ features built-in 10GbE connectivity for data rates up to 1,181 MB/s. Larger units like the DS1825+ support networking upgrades reaching up to 25GbE with maximum speeds of 2,239 MB/s. The RS1221RP+ also provides a PCIe expansion slot for interface upgrades.
Can you add M.2 NVMe SSD cache drives to Synology desktop enclosures?
Yes, specific Synology enclosures include dedicated slots to install high-speed solid-state cache. The DS920+ provides dual built-in M.2 NVMe slots designed explicitly for SSD caching without consuming standard drive bays. This hardware configuration improves input and output operations while leaving all four 3.5-inch SATA hard drive bays open for primary data storage pools.
Which Synology enclosures fit into shallow-depth server racks?
Synology offers short-depth rackmount chassis specifically engineered for compact or two-post server racks. The RX418 provides a four-bay rackmount expansion unit measuring 325 mm deep, making it suitable for wall-mount cabinets and shallow deployments. For an eight-bay primary system, the RS1221RP+ utilizes a short-depth rack design that fits tighter enclosures while retaining redundant power capabilities.
How much system memory do high-capacity Synology desktop enclosures include?
Memory capacity varies based on the enclosure tier and processor hardware. Compact desktop options like the DS423 include 2GB of RAM, while four-bay and eight-bay units such as the DS920+ and RS1221RP+ come with 4GB of RAM. High-performance enterprise desktop platforms like the DS3622xs+ feature 16GB of RAM alongside a 6-core Xeon processor for demanding workloads.
How many hard drives can you connect to a Synology expansion unit?
Drive capacity depends on the specific expansion unit model you attach to your primary system. The RX418 adds four drive bays, while the DX525 expands your setup by five hot-swappable SATA bays. For larger enterprise environments, the DX1215II, RX1217, and RX1223RP each deliver twelve additional drive bays to scale out raw storage capacity without requiring complete system replacements.