Hardware Specifications
CPU
CPU Model Intel Celeron J3355
CPU Architecture 64-bit
CPU Frequency Dual Core 2.0 burst up to 2.5GHz
Hardware Encryption Engine (AES-NI)  YES
Hardware Transcoding Engine H.264 (AVC), H.265 (HEVC), MPEG-2 and VC-1; maximum resolution: 4K (4096 x 2160); maximum frame rate per second (FPS): 30
Memory
System Memory 2GB DDR3L
Memory Module Pre-installed 2GB (1x 2GB)
Total Memory Slots 2
Memory Expandable up to 6GB (2GB + 4GB)
Storage
Drive Bays 4
Compatible Drive Type
  • 3.5" SATA HDD
  • 2.5" SATA HDD
  • 2.5" SATA SSD
Maximum Internal Raw Capacity 56TB (14 TB drive x4) (Capacity may vary by RAID types)
Maximum Single Volume Size 108TB
Hot Swappable Drive  YES
Notes
  • "Compatible drive type" indicates the drives that have been tested to be compatible with Synology products. This term does not indicate the maximum connection speed of each drive bay.
  • The maximum single volume size is not directly related to the maximum raw capacity.
  • Expansion of the internal volume is only supported if the combined single volume size does not exceed the maximum limit of 108TB.
External Ports
RJ45 1GbE LAN Port 2 (with Link Aggregation / Failover support)
USB 3.0 Port 2
File System
Internal Drives
  • Btrfs
  • EXT4
External Drives
  • Btrfs
  • EXT4
  • EXT3
  • FAT
  • NTFS
  • HFS+
  • exFAT*
Notes exFAT Access is purchased separately in Package Center.
Appearance
Size (Height x Width x Depth) 166mm x 199mm x 223mm 
Weight 2.23kg 
Others
System Fan 92mm x 92mm x 2pcs
Fan Speed Mode
  • Full-Speed Mode
  • Cool Mode
  • Quiet Mode
Brightness adjustable front LED indicators  YES
Power Recovery  YES
Noise Level* 20.5dB(A) 
Scheduled Power On/Off  YES
Wake on LAN/WAN  YES
Power Supply Unit / Adapter 90W 
AC Input Power Voltage 100V~240V AC
Power Frequency 50/60Hz, Single Phase
Power Consumption* 29.01W (Access) 
10.59W (HDD Hibernation) 
British Thermal Unit 98.98BTU/hr (Access) 
36.12BTU/hr (HDD Hibernation) 
Environment Temperature
Operating Temperature 5°C~40°C (40°F~104°F)
Storage Temperature -20°C~60°C (-5°F~140°F)
Relative Humidity 5%~95% RH
Certification
  • EAC
  • CCC
  • RCM
  • KC
  • FCC
  • CE
  • BSMI
Warranty 2 Years
Notes
  • Power consumption is measured when fully loaded with Western Digital 1TB WD10JFCX hard drive(s).
  • Noise Level Testing Environment: Fully loaded with Seagate 2TB ST2000VN000 hard drive(s) in idle; Two G.R.A.S. Type 40AE microphones, each set up at 1 meter away from the Synology NAS front and rear; Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%
DSM Specifications 
Storage Management
Maximum Internal Volume Number 256
Maximum iSCSI Target Number 128
Maximum iSCSI LUN 256
SSD TRIM  YES
Supported RAID Type
  • Synology Hybrid RAID
  • Basic
  • JBOD
  • RAID 0
  • RAID 1
  • RAID 5
  • RAID 6
  • RAID 10
RAID Migration
  • Basic to RAID 1
  • Basic to RAID 5
  • RAID 1 to RAID 5
  • RAID 5 to RAID 6
Volume Expansion with Larger HDDs
  • Synology Hybrid RAID
  • RAID 1
  • RAID 5
  • RAID 6
Volume Expansion by Adding a HDD
  • Synology Hybrid RAID
  • RAID 5
  • JBOD
Global Hot Spare Supported RAID Type
  • Synology Hybrid RAID
  • RAID 1
  • RAID 5
File Sharing Capacity
Maximum Local User Accounts 2048
Maximum Local Groups 256
Maximum Shared Folder 256
Maximum Shared Folder Sync Tasks 4
Maximum Concurrent CIFS/AFP/FTP Connections 200
Maximum Concurrent CIFS/AFP/FTP Connections (with RAM expansion) 300
Windows Access Control List (ACL) Integration  YES
NFS Kerberos Authentication  YES
Log Center  YES
Syslog Events per Second 400
Add-on Packages 
Antivirus by McAfee (Trial)  YES
Chat  YES
Maximum Users 1000
Notes
  • The number of concurrent HTTP connections for Chat was configured to the maximum.
  • CPU and RAM usage were both under 80% when the number of maximum users was reached.
  • For tested models with expandable memory, the maximum amount of RAM was installed.
Cloud Station Server  YES
Maximum Number of Concurrently Connected Devices 200
Maximum Number of Concurrently Connected Devices (with RAM expansion) 300
Maximum Number of Hosted Files (btrfs) 1,000,000
Maximum Number of Hosted Files (ext4) 1,000,000
Notes
  • The maximum number of concurrently connected devices refers to the maximum number of devices that can remain connected at the same time.
  • The maximum number of hosted files refers to the maximum number of files that can be indexed and hosted by the Cloud Station Server service. RAM expansion was not used during testing.
  • Non-encrypted shared folders were used during the aforementioned testing.
Download Station  YES
Maximum Concurrent Download Tasks 80
Drive  YES
Maximum Number of Hosted Files 500,000
Maximum Number of Concurrent Connections for PC Clients 450
Notes
  • The Btrfs file system was used for the purpose of testing.
  • The maximum number of hosted files refers to the maximum number of files that can be indexed and hosted by the Drive service.
  • The maximum number of concurrent connections refers to the maximum number of connections that can be maintained when the maximum number of hosted files was reached.
  • For tested models with expandable memory, the maximum amount of RAM was installed.
  • Non-encrypted shared folders were used during the aforementioned testing.
exFAT Access (optional)  YES
MailPlus / MailPlus Server  YES
Free Email Accounts 5 (Licenses required for additional accounts)
Maximum number of concurrent users Up to 50
Maximum Server Performance 623,000 emails per day, approx. 19GB
Notes
  • The CPU and RAM usage were both under 80% when testing the maximum number of concurrent users.
  • For tested models with expandable memory, the maximum amount of RAM was installed.
  • Read-write SSD cache was enabled in 5-bay (and above) NAS models with 2 SSDs units installed.
  • The performance of the mail system will slightly decrease in high-availability mode due to data synchronization between the two servers.
  • Functions that were enabled in all of the tests above: anti-spam, anti-virus, DNSBL, greylist, content scan, full-text search (English only).
Media Server  YES
DLNA Compliance  YES
Moments  YES
Facial recognition  YES
Subject recognition  YES
Office  YES
Maximum Users 400
Notes
  • Multiple files were opened for testing and each file was edited by 30 users simultaneously.
  • CPU and RAM usage were both under 80% when the number of maximum users was reached.
  • For tested models with expandable memory, the maximum amount of RAM was installed.
  • Client performance may affect maximum simultaneous editing users. Client PCs used for testing: Intel Core i3-3220 / 8GB RAM
Snapshot Replication  YES
Maximum Snapshots per Shared Folder 1024
Maximum of system snapshots 65536
Surveillance Station YES 
Maximum IP cam (Licenses required) 25 (including 2 Free License) 
Total FPS (H.264)* 750 FPS @ 720p (1280x720) 
375 FPS @ 1080p (1920×1080) 
250 FPS @ 3M (2048x1536) 
200 FPS @ 5M (2591x1944) 
120 FPS @ 4K (3840x2160)
Total FPS (H.265)* 750 FPS @ 720p (1280x720) 
750 FPS @ 1080p (1920×1080) 
450 FPS @ 3M (2048x1536) 
250 FPS @ 5M (2591x1944) 
200 FPS @ 4K (3840x2160)
Total FPS (MJPEG)* 450 FPS @ 720p (1280x720) 
250 FPS @ 1080p (1920×1080) 
160 FPS @ 3M (2048x1536) 
130 FPS @ 5M (2591x1944)
Notes Surveillance Station throughput is tested with Axis network camera, using continuous recording with live view from Surveillance Station and motion detection by camera. Live view and recording are sharing the same stream from the camera.
Video Station  YES
Video Transcoding 4K Group 1
Maximum Transcoding Channel Number 2 channel, 30 FPS @ 4K (4096 x 2160), H.264 (AVC)/H.265 (HEVC) or 
2 channel, 30 FPS @ 1080p (1920×1080), H.264 (AVC)/H.265 (HEVC)/MPEG-2/VC-1
Notes  YES
VPN Server  YES
Maximum Connections 20
Environment & Packaging
Environment RoHS Compliant
Packaging Content
  • Main Unit X 1
  • Accessory Pack X 1
  • AC Power Adapter X 1
  • AC Power Cord X 1
  • RJ-45 LAN Cable X 2
  • Quick Installation Guide X 1