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Expansion Unit DX1215II

Plug-and-play storage expansion for Synology DiskStation

DX1215II
DX1215II

Easily add 12 bays to your DiskStation

With its 12-bay desktop form factor, the DX1215II provides generous storage expansion for Synology DiskStation1 whenever needed with minimal impact on the deployment footprint.

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Online volume and storage expansion

Add a new volume to your storage, or seamlessly expand RAID volumes on Synology DiskStation without reformatting drives with online volume expansion through DiskStation Manager (DSM) to minimize service disruptions.

Online volume and storage expansion

Backed by Synology drives

Engineered to handle intensive 24/7 workloads, Synology drives consistently deliver top-grade performance.2

Enterprise Series 3.5" SATA Plus Series 3.5" SATA
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Simple setup and management

Plug-and-play design makes adding the DX1215II to an existing DiskStation simple. Unified drive management through DSM ensures health monitoring, storage allocation, and maintenance tasks are centralized and easily accessible to administrators.

Simple setup and management
5-year warranty

5-year warranty

At Synology, we are committed to product innovation and quality. Synology guarantees a robust and reliable data management experience with a 5-year limited warranty,3 providing responsive technical support and hardware replacement services to maximize your return on investment. Learn more

Synology Replacement Service (SRS)

Synology Replacement Service (SRS)

SRS provides free advance replacement units as early as the next business day in selected regions, maximizing the service uptime for your mission-critical storage and ensuring your business continuity. Learn more

Notes:

  1. View specifications for a list of supported models. Requires DSM 6.2.4-25556 or newer to be installed on the host device.

  2. Storage drives are sold separately. Refer to the compatibility list for compatible devices.

  3. The warranty period starts from the date of purchase as stated on your purchase receipt. Visit https://www.synology.com/company/legal/warranty for more information.

Hardware Specifications
Applied Models
Applied Models
 Supports creating volumes across different units
  • FS series:FS1018
  • 19 series:DS2419+II, DS2419+
  • 18 series:DS3018xs
  • 17 series:DS3617xsII, DS3617xs
  • 15 series:DS3615xs, DS2415+, DS2015xs
  • 13 series:DS2413+
  • 12 series:DS3612xs
  • 11 series:DS3611xs, DS2411+
Notes
  • To have better performance, we recommend creating storage volumes physically located within the same NAS or Expansion Unit, rather than creating volumes across your NAS and Expansion Unit.
  • DSM version requirement: 6.2.4-25556 or later version.
Storage
Storage
 Drive Bays 12
Compatible Drive Type* (See all supported drives)
  • 3.5" SATA HDD
  • 2.5" SATA HDD
  • 2.5" SATA SSD
Hot Swappable Drive*
RAID Management through Synology DSM
Notes Synology only guarantees full functionality, reliability, and performance for Synology drives listed on the compatibility list. The use of non-validated components may limit certain functionality and result in data loss and system instability.
External Ports
External Ports
 Expansion Port 1
Appearance
Appearance
 Size (Height x Width x Depth) 270 mm x 300 mm x 340 mm
Weight 9.02 kg
Power
Power
 Power Recovery Synchronized with the Synology DiskStation
Power Supply Unit / Adapter 550 W
AC Input Power Voltage 100V to 240V AC
Power Frequency 50/60 Hz, Single Phase
Power Consumption 51.23 W (Access)
21.71 W (HDD Hibernation)
British Thermal Unit 174.69 BTU/hr (Access)
74.03 BTU/hr (HDD Hibernation)
Notes Power consumption is measured when it is fully loaded with Western Digital 1TB WD10EFRX hard drive(s).
Temperature
Temperature
 Operating Temperature 5°C to 35°C (40°F to 95°F)
Storage Temperature -20°C to 60°C (-5°F to 140°F)
Relative Humidity 5% to 95% RH
Others
Others
 System Fan 120 mm x 120 mm x 2 pcs
Easy Replacement System Fan
Noise Level* 27.2 dB(A)
Notes Noise Level Testing Environment: Fully loaded with Seagate ST2000VN000 hard drive(s) in the idle state. Two G.R.A.S. Type 40AE microphones, each set up 1 meter away from the Synology expansion unit at the front and rear. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%.
Certification
Certification
  • FCC
  • CE
  • BSMI
  • EAC
  • RCM
  • KC
Warranty
Warranty
 5 Years
Notes The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
Environment & Packaging
Environment
Environment
 RoHS Compliant
Packaging Content
Packaging Content
  • Main Unit X 1
  • User's Guide X 1
  • Accessory Pack X 1
  • AC Power Cord X 1
  • Expansion Cable: Infiniband X 1
Optional Accessories
Optional Accessories

Notes:

  1. Model specifications are subject to change without prior notice.
  2. The figures are based on Synology internal testing. Each performance test is done individually. No other services or applications are processed at the same time.
  3. The actual performance may be lower than lab testing figure due to differences in server configuration, deployment, and the number of active operations.
  4. If usage requirements exceed the specifications above, please contact our regional partners for professional advice.