Synology Expansion Unit DX517 – 5-Bay Storage Expansion

The Synology Expansion Unit DX517 – 5-Bay Storage Expansion is a flexible and reliable storage expansion solution designed for Synology DiskStation and RackStation NAS models. Featuring five hot-swappable 3.5″/2.5″ SATA drive bays, the DX517 allows businesses and advanced users to expand their NAS capacity instantly without downtime.

With plug-and-play integration, Synology Hybrid RAID (SHR) support, and automatic volume expansion, this unit is ideal for growing data storage needs, backup solutions, and high-capacity applications.

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Drive Bays

• 5 x 3.5″/2.5″ SATA HDD/SSD (hot-swappable)
• Supports both SATA III (6Gb/s) and SATA II (3Gb/s) drives

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Storage Expansion

• Expands the storage capacity of supported DiskStation and RackStation models
• Automatic volume expansion without system downtime
• Supports creation of new volumes for independent storage use
• Compatible with Synology Hybrid RAID (SHR), JBOD, RAID 0, 1, 5, 6, 10

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Connectivity

• Interface: 1 × eSATA (dedicated connection to host NAS)
• Max Bandwidth: 6 Gb/s transfer speed via eSATA

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Performance

• Plug-and-play setup ensures minimal downtime
• Integrated with Synology DSM for centralized storage management
• Supports SSD cache with compatible drives for improved performance

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Design & Build

• Hot-swappable drive trays for quick installation and replacement
• Compact and quiet design for office/server room environments
• Equipped with smart-controlled fan for efficient cooling

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Power & Efficiency

• Power Supply: External 100 W
• Power Consumption:
  • ~21 W (access)
  • ~9 W (HDD hibernation)

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Physical Specifications

• Dimensions (H × W × D): 157 × 248 × 233 mm
• Weight: ~3.9 kg (without drives)

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Compatibility

• Works with select Synology DiskStation and RackStation models
• Supported models can be expanded up to their maximum capacity with DX517

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Warranty & Support

• Warranty: 3 Years (extendable in some regions)

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Typical Use Cases

• Seamless NAS expansion for growing business data
• Backup storage for critical workloads
• Media archiving for creative teams
• Surveillance video retention with Surveillance Station

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Key Features

• 5 hot-swappable 3.5″/2.5″ SATA drive bays
• eSATA connectivity with 6 Gb/s bandwidth
• Plug-and-play volume expansion with no downtime
• Supports Synology SHR and multiple RAID levels
• Compact, efficient, and quiet design

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Meta Description

Synology Expansion Unit DX517 – 5-Bay Storage Expansion with 5 hot-swappable SATA drive bays, eSATA connectivity, and support for SHR/RAID. Expand your DiskStation or RackStation storage seamlessly without downtime.

Datasheet