��� NAS � Synology DS1621+

CPU Model
AMD Ryzen V1500B
CPU Architecture
64-bit
CPU Frequency
4-core 2.2 GHz
Hardware Encryption Engine (AES-NI)

System Memory
4 GB DDR4 ECC SODIMM
Memory Module Pre-installed
4 GB (4 GB x 1)
Total Memory Slots
2
Maximum Memory Capacity
32 GB (16 GB x 2)
Notes
• Please select Synology memory modules for optimum compatibility and reliability. Synology will not provide complete product warranty or technical support if non-Synology memory modules are used for memory expansion.
• Synology reserves the right to replace memory modules with the same or higher frequency based on supplier's product life cycle status. Rest assured that the compatibility and stability have been strictly verified with the same benchmark to ensure identical performance

Drive Bays
6
Maximum Drive Bays with Expansion Unit
16 (DX517 x 2)
M.2 Drive Slots
2 (NVMe)
Compatible Drive Type*
3.5" SATA HDD
2.5" SATA HDD
2.5" SATA SSD
M.2 2280 NVMe SSD
Maximum Single Volume Size*
108 TB
Hot Swappable Drive
Notes
• "Compatible drive type" indicates drives that have been tested to be compatible with Synology products. This term does not indicate the maximum connection speed of each drive bay.
• Each internal volume (may consist of multiple drives) is expandable up to 108TB.

RJ-45 1GbE LAN Port
4 (with Link Aggregation / Failover support)
USB 3.0 Port
3
eSATA Port
2

PCIe Expansion
1 x Gen3 x8 slot (x4 link)

Internal Drives
• Btrfs
• EXT4
External Drives
• Btrfs
• EXT4
• EXT3
• FAT
• NTFS
• HFS+
• exFAT*
Notes
exFAT Access is purchased separately in Package Center.

Size (Height x Width x Depth)
166 mm x 282 mm x 243 mm
Weight
5.1 kg

System Fan
92 mm x 92 mm x 2 pcs
Fan Speed Mode
• Full-Speed Mode
• Cool Mode
• Quiet Mode
Easy Replacement System Fan
Brightness Adjustable Front LED Indicators
Power Recovery
Noise Level*
25.2 dB(A)
Scheduled Power On / Off
Wake on LAN / WAN
Power Supply Unit / Adapter
250 W
AC Input Power Voltage
100 V to 240 V AC
Power Frequency
50/60 Hz, Single Phase
Power Consumption*
51.22 W (Access)
25.27 W (HDD Hibernation)
British Thermal Unit
174.77 BTU/hr (Access)
86.22 BTU/hr (HDD Hibernation)
Notes
• Power consumption is measured when it is fully loaded with Western Digital 1TB WD10EFRX hard drive(s).
• Noise Level Testing Environment: Fully loaded with Seagate 2TB 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 NAS at the front and rear. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%

Operating Temperature
0°C to 40°C (32°F to 104°F)
Storage Temperature
-20°C to 60°C (-5°F to 140°F)
Relative Humidity
5% to 95% RH
RoHS Compliant

FCC
CE
BSMI
EAC
CCC
KC
VCCI
RCM

Storage Management
Maximum Internal Volume Number: 64
SSD Read / Write Cache (White Paper)
SSD TRIM
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
• RAID 10
Volume Expansion by Adding a HDD
• Synology Hybrid RAID
• JBOD
• RAID 5
• RAID 6
Global Hot Spare Supported RAID Type
• Synology Hybrid RAID
• RAID 1
• RAID 5
• RAID 6
• RAID 10
File Services
File Protocol CIFS/AFP/NFS/FTP/WebDAV
Maximum Concurrent CIFS/AFP/FTP Connections 1,000
Maximum Concurrent CIFS/AFP/FTP Connections (with RAM expansion) 2,000
Windows Access Control List (ACL) Integration
NFS Kerberos Authentication
Notes
• Regarding data concerning tests with RAM expansion, all memory slots are installed with the maximum capacity of supported RAM.
• The testing standard was based on the maximum number of concurrent connections supported by this model. During the testing, 25% of the connections were used to transfer files concurrently. The transfer process guaranteed that the connections were not interrupted; the minimum transfer speed was not guaranteed.
Account & Shared Folder
Maximum Local User Accounts 2,048
Maximum Local Groups 256
Maximum Shared Folder 512
Maximum Shared Folder Sync Tasks 16
High Availability
Synology High Availability
Log Center
Syslog Events per Second 800
Virtualization
VMware vSphere 6 with VAAI
Windows Server 2016
Windows Server 2019
Citrix Ready
OpenStack
General Specifications
Networking Protocols SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV
Supported Browsers
• Google Chrome
• Firefox
• Microsoft Edge
• Internet Explorer 10 onwards
• Safari 10 onwards
• Safari (iOS 10 onwards)
• Google Chrome (Android 6.0 onwards)
Supported Language
English, Deutsch, Français, Italiano, Español, Dansk, Norsk, Svenska, Nederlands, Русский, Polski, Magyar, Português do Brasil, Português Europeu, Türkçe, Český, ภาษาไทย, 日本語, 한국어, 繁體中文, 简体中文
Add-on Packages
Antivirus by McAfee (Trial)
Central Management System
Synology Chat
Maximum Users 1,500
Notes
• The number of concurrent HTTP connections for Synology Chat was configured to the maximum.
• For tested models with expandable memory, the maximum amount of RAM was installed.
Document Viewer
Download Station
Maximum Concurrent Download Tasks 80
exFAT Access (Optional)
iSCSI Manager
Maximum iSCSI Target Number 128
Maximum iSCSI LUN 256
iSCSI LUN Clone/Snapshot, Windows ODX
Synology MailPlus / MailPlus Server
Free Email Accounts 5 (Licenses required for additional accounts)
Maximum Number of Concurrent Users 150
Maximum Server Performance 1,484,000 emails per day, approx. 45GB
Notes
• Models with more than 4 bays were installed with two SSDs for SSD cache.
• For tested models with expandable memory, the maximum amount of RAM was 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
DLNA Compliance
Moments
Facial Recognition
Subject Recognition
Auto Color & Rotate
Moments Select
Snapshot Replication
Maximum Snapshots per Shared Folder 1,024
Maximum of System Snapshots 65,536
Surveillance Station
Maximum IP cam (Licenses required) 40 (including 2 Free License) (See All Supported IP Cameras)
Total FPS (H.264) 1200 FPS @ 720p (1280x720)
1050 FPS @ 1080p (1920x1080)
600 FPS @ 3M (2048x1536)
440 FPS @ 5M (2591x1944)
320 FPS @ 4K (3840x2160)
Total FPS (H.265) 1200 FPS @ 720p (1280x720)
1200 FPS @ 1080p (1920x1080)
1120 FPS @ 3M (2048x1536)
600 FPS @ 5M (2591x1944)
480 FPS @ 4K (3840x2160)
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.
• The maximum channel number also includes devices installed on Virtual DSM.
• Total FPS may be affected by other services running at the same time (e.g., archive tasks performed by Archive Vault).
Synology Drive
Recommended Number of Hosted Files 1,000,000 (applies to files indexed or hosted by Synology Drive. For file access through other standard protocols, refer to the File Services section above)
Recommended Number of Concurrent Sync Clients 550 (the number of connections that can be maintained when the recommended number of hosted files was reached)
Notes
• Exceeding the recommended numbers above will not block application operations, but may result in longer response time.
• Utilizing SSD cache can significantly improve performance.
• For tested models with expandable memory, the maximum amount of RAM was installed.
• Btrfs file system and non-encrypted shared folders were used during the aforementioned testing.
Synology Office
Maximum Users 1,800
Notes
• Multiple files were opened for testing and each file was edited by 30 users simultaneously.
• 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
Video Station
Virtual Machine Manager
Recommended Virtual Machine Instances 8 (Learn more)
Recommended Virtual DSM Number (Licenses required) 8 (including 1 Free License)
Notes The specifications vary depending on system configuration and memory size.
VPN Server
Maximum Connections 30