DiskStation DS1621xs+
On-premises cloud solution built for performance


High-end scalable NAS in desktop form factor
DS1621xs+ is a high-end NAS with server-class performance in a 6-bay desktop form factor. The built-in M.2 SSD cache slots, 10GbE port, expandable memory, and scalable storage design allow you to boost the performance of your NAS, making it ideal for small and medium-sized businesses that need an efficient and space-saving storage solution.

CPU - Intel® Xeon D-1527 4-core 2.2 GHz
Memory - 8 GB DDR4 ECC SODIMM, up to 32 GB
High Performance - Over 3,100 MB/s sequential read
Scalability - Up to 16 drives with DX517


Supercharge your storage with speedy performance
DS1621xs+ comes with built-in M.2 SSD cache slots capable of providing I/O response speeds 20 times faster than hard drives without occupying front drive bays. The built-in 10GbE port provides fast data transmission and can be bonded with an additional network interface card for higher network bandwidth.

M.2 SSD support
Dual M.2 2280 SSD supporting NVMe SSDs

10GbE support
Built-in 10GBASE-T for bandwidth intensive environments

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, providing responsive technical support and hardware replacement services to maximize your return on investment.

Ultimate Backup Solution

DS1621xs+ integrates various backup applications into an intuitive user interface, offering durable storage technologies to safeguard your valuable data on any device.

Active Backup for Business
Centralize backup tasks for VMware, Windows, and file servers. Restore whatever you want fast and reliably when needed.
Learn more

Hyper Backup
Comprehensively back up your data to a local shared folder, an external device, another Synology NAS, an rsync server, or a public cloud to ensure data safety.
Learn more

Synology Drive
Safeguard your computer with Synology Drive Client. Effortlessly perform real-time data backups and point-in-time file recovery.
Learn more


Active Backup for

Office 365 / G Suite
On-premise backup solution with a centralized dashboard. Optimize storage efficiency with single instancing and block-level deduplication technology.

Office 365 G Suite 
Real-time collaboration on your private cloud
Synology Office is a collaboration package combining the convenience and usability of public clouds with the data privacy and security guaranteed by private clouds. It allows you to work seamlessly together on documents and spreadsheets in a protected environment. Learn more

Real-time collaboration on the same online documents to boost productivity,

Instant communication on Synology Chat during the editing of documents or spreadsheets

Version control for you to navigate all the changes and retrieve previous versions with just a click


Virtual Machine Manager
Virtual Machine Manager enables you to test new software in sandboxes, isolate your customers' machines, and increase the flexibility of your server. You can easily run Windows, Linux, and Virtual DSM on your Synology NAS by just a few steps. Learn more

Snapshots for virtual machines
Perfectly clone and restore a virtual machine within seconds.

Live migration
Seamlessly migrate Virtual DSM instances from a Synology NAS to another.

Multi-tenant environment
Create multiple isolated virtual machines for subsidiary business units or departments.


Powered by Synology DSM

Central Management System
Manage multiple Synology NAS servers simultaneously on a centralized interface to increase business efficiency.

Learn more
Synology MailPlus
Secure, reliable, and private mail server solution with an intuitive and modern mail client.

Learn more
Synology High Availability
Seamless transition between clustered servers in the event of a server failure to minimize the impact on applications.

Learn more
Security
Comprehensive built-in security tools are constantly updated to protect your devices against evolving threats.

Learn more
Synology Drive
A versatile solution for file management and synchronization. 

Learn more
Surveillance Station
Complete surveillance solution for recording, monitoring, and management.



Hardware Specs

CPU CPU Model Intel Xeon D-1527   CPU Architecture 64-bit   CPU Frequency 4-core 2.2 (base) / 2.7 (turbo) GHz   Hardware Encryption Engine (AES-NI)   Memory System Memory 8 GB DDR4 ECC SODIMM   Memory Module Pre-installed 8 GB (8 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. For more information on the recommended memory configurations, visit here. 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. Storage Drive Bays 6   Maximum Drive Bays with Expansion Unit 16 (DX517 x 2)   M.2 Drive Slots 2 (NVMe)   Compatible Drive Type* (See all supported drives) 3.5" SATA HDD 2.5" SATA HDD 2.5" SATA SSD M.2 2280 NVMe SSD   Maximum Single Volume Size* 200 TB (32 GB RAM required, for RAID 5 or RAID 6 groups only) 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 expandble up to 108TB (with memory less than 32GB) or 200TB (with memory equal to or greater than 32GB). External Ports RJ-45 1GbE LAN Port 2 (with Link Aggregation / Failover support)   RJ-45 10GbE LAN Port 1   USB 3.0 Port 3   eSATA Port 2 PCIe PCIe Expansion 1 x Gen3 x8 slot (x8 link) 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) 166 mm x 282 mm x 243 mm   Weight 5.3 kg Others 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* 62.85 W (Access)
34.26 W (HDD Hibernation)   British Thermal Unit 214.45 BTU/hr (Access)
116.89 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% Temperature 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 Certification EAC VCCI CCC RCM KC FCC CE BSMI Warranty 5 Years   Notes The warranty period starts from the purchase date as stated on your purchase receipt.  Environment RoHS Compliant Packaging Content Main Unit X 1 Accessory Pack X 1 AC Power Cord X 1 RJ-45 LAN Cable X 2 Quick Installation Guide X 1 Optional Accessories DDR4 ECC SODIMM: D4ES01-8G DDR4 ECC SODIMM: D4ECSO-2666-16G Expansion Units: DX517 2.5" SATA SSD: SAT5200 M.2 2280 NVMe SSD: SNV3400 10GbE Network Interface Card: E10G18-T2/E10G18-T1/E10G17-F2 VisualStation: VS960HD/VS360HD Surveillance Device License Pack   Notes All memory modules will operate at the maximum frequency specified by the CPU manufacturer. Notes: Model specifications are subject to change without prior notice. The figures are based on Synology internal testing. No other services or applications are processed during the performance tests.