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RackStation RS3621xs+

RackStation RS3621xs+

High-performance enterprise storage built for data accuracy and security.

Product Image RS3621xsplus
Product Image RS3621xsplus
  • Features
  • Specs
Trusted by professionals across all industries.
Synology is a solid storage with great capabilities out of the box. The licensing model of all-inclusive software adds great value to the product.
Information Technology Manager - Government
Synology provides a single-platform solution for all of our backup needs in a cost effective manner.
Director of Enterprise Infrastructure - Education
Synology's DSM is a masterpiece, designed to be user-friendly even for non-IT professionals, helping us become less reliant on out IT teams.
Director Media Services - Media
Working with Synology Products has just been the best. Its an all in one product that can cater for all aspects of Storage.
Senior Systems Engineer - Media
The Synology brand is very feature-rich and unbeatable in terms of price/performance in the NAS segment. Our current testing was primarily focused on backup, which delivered reliability alongside adequate performance.
CEO - IT Services
Smooth storage server setup with intuitive OS and reliable automation features
Server Administrator - Retail
Accelerate your business operations The 12-bay RS3621xs+ is capable of delivering over 238K 4K random read IOPS and 5,819 MB/s sequential read throughput— a true enterprise powerhouse. With full power supply redundancy, an 8-core processor, ECC memory, advanced snapshot technology, and file self-healing, the RS3621xs+ provides a reliable foundation to any data-driven business. Download Datasheet ComputeIntel® Xeon® D-1541 8-core 2.1 GHzNetworkingBuilt-in dual-port 10GbEMemory8 GB ECC DDR4 Up to 64 GBScalabilityUp to 36 drive bays with RX1217RP/RX1217

Storage you can trust

The RS3621xs+ keeps your data protected while you concentrate on delivering the best results to your customers — even when disaster strikes.

Redundant power

Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans allow them to be replaced without powering down the system.

Maximize service availability

Synology High Availability (SHA) pairs two identical units together creating an active-passive cluster with minute-level failover. Learn more

Next-generation file system

Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots. Learn more

Storage you can trust
Tailored to your businessThe RS3621xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment.Double bandwidthUpgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.SSD cacheBoost read/write IOPS by up to 16 times by enabling SSD cache with our Synology M.2 NVMe adapter cards and SNV3500 SSDs or by installing one or more 2.5” SAT5200 SSDs.Storage expansionQuickly and easily scale up to 36 drives with two RX1217RP/RX1217 expansion units.License-free data protection
Keep disaster at bay

Hyper Backup

A comprehensive backup and recovery solution for securing data stored on Synology servers. Backup data locally, to another Synology device, rsync server, or cloud-based storage such as Google Drive, Dropbox, S3-compatible destinations, and Synology C2. Deduplication, integrity checks, and incremental transfer technology reduce bandwidth and storage used. Learn more

Snapshot Replication

Easily schedule flexible point-in-time backups of shared folders and iSCSI LUNs with an RPO as low as 5 minutes and recovery in seconds. Set up replication and failover to other Synology storage systems for fast RTOs and minimal service disruption. Learn more

Backup your entire IT infrastructure

Active Backup Suite

Enables administrators to easily backup the entire IT infrastructure to their NAS, including Windows & Linux workstations and servers, file servers, VMware and Hyper-V virtual machines, and Microsoft 365 and Google Workspace accounts. Backups benefit from deduplication, multiversioning, and optimizations to reduce bandwidth and storage used. Learn more

Storage for virtualizationSynology iSCSI storage supports mainstream virtualization solutions with an easy management interface to enhance usability. VMware vSphere 6.5 and VAAI integration helps offload storage operations. Windows Offloaded Data Transfer (ODX) speeds up data transfer. OpenStack Cinder support turns your Synology NAS into a block-based storage component. Additionally, Synology Storage Console enables even more simplified storage provisioning and management options in VMware and Windows environments.Learn more

Complete surveillance solution

Synology Surveillance Station transforms the RS3621xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios. Learn more

Secure and private

AES-256 encryption adds additional security to the locally-stored footage.

Access from anywhere, anytime

Access recordings and live streams whenever you want using a web browser, desktop client, or the DS cam mobile app.

Real-time alerts

Email, SMS, or push notifications alert you when incidents occur or predefined conditions are met.

Complete surveillance solution

Works best with Synology drives

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

HDD
Enterprise Series 3.5" SATA
SSD
Enterprise Series 2.5" SATA Enterprise Series M.2 NVMe
Enterprise Series 3.5" SATAEnterprise Series 2.5" SATAEnterprise Series M.2 NVMe

Powered by Synology DiskStation Manager

The RS3621xs+ runs Synology DiskStation Manager (DSM), the web-based operating system with applications and services designed specifically for businesses.

Central Management System

Conveniently manage your fleet of Synology NAS from a centralized console.

Learn more

Synology Drive

Instantly access your NAS files across multiple devices whenever you want, wherever you are.

Learn more

Collaboration Suite

Satisfy all team collaboration needs behind the safety of your own private cloud with Synology Office, Calendar, and Chat.

Learn more

Virtual Machine Manager

Run various operating systems in isolated sandboxes. Seamlessly clone, store, and migrate virtual machines.

Learn more

Security

Shield your Synology NAS from the most sophisticated threats with industry-leading security solutions.

Learn more

Public Cloud Integration

Back up and synchronize data easily between public cloud accounts and your NAS.

Learn more

5-year warranty

At Synology, we are committed to product innovation and quality. The RS3621xs+ is backed by a 5-year limited warranty that includes technical support and hardware replacement services to maximize your return on investment. Learn more

Hardware Overview
  • 1Power button and indicator
  • 2Alert Off Button
  • 3Drive tray
  • 4Drive status indicator
  • 5Power Port
  • 6PSU Indicators & Alert Off Buttons
  • 7PSU fan
  • 8Console port
  • 91GbE/10GbE RJ-45 Ports
  • 10USB 3.2 Ports
  • 11Expansion port
  • 12PCIe expansion slot
  • 13Reset button
  • First Product Image
  • Second Product Image
  • Third Product Image
  • Fourth Product Image
  • Fifth Product Image
  • Sixth Product Image
Notes:Gartner® and Peer Insights™ are trademarks of Gartner, Inc. and/or its affiliates. All rights reserved. Gartner Peer Insights content consists of the opinions of individual end users based on their own experiences, and should not be construed as statements of fact, nor do they represent the views of Gartner or its affiliates. Gartner does not endorse any vendor, product or service depicted in this content nor makes any warranties, expressed or implied, with respect to this content, about its accuracy or completeness, including any warranties of merchantability or fitness for a particular purpose.Performance testing conducted by Synology with 10GbE NICs installed. Actual results may vary depending on system configuration, testing methods, and other environmental variables. Check the performance page for additional details.Network adapter cards, expansion units, other PCIe add-in cards, and storage drives are sold separately. Refer to the compatibility list for compatible devices.SSD cache can be enabled by using compatible 2.5" SSDs or without occupying drive bays by installing Synology SNV3500 M.2 22110 NVMe SSDs using M2D20 or E10M20-T1 adapter cards, sold separately.Users have reported total data size reductions of more than 50% when backing up multiple systems with deduplication technology.Surveillance Station includes 2 free licenses. Connecting more cameras and devices requires additional licenses.
Hardware Specs
Hardware Specs
Hardware Specifications
CPU
CPU
CPU Model Intel Xeon D-1541
CPU Quantity 1
CPU Core 8
CPU Architecture 64-bit
CPU Frequency 2.1 (base) / 2.7 (turbo) GHz
Hardware Encryption Engine
Memory
Memory
System Memory 8 GB DDR4 ECC UDIMM
Memory Module Pre-installed 8 GB (8 GB x 1)
Total Memory Slots 4
Maximum Memory Capacity 64 GB (16 GB x 4)
Notes
  • 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.
  • 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 multi-module memory configurations, all modules must be identical and share the same model number. Check the Product Manual of your Synology product for recommended memory configurations.
Storage
Storage
Drive Bays 12
Maximum Drive Bays with Expansion Unit 36 (RX1217 x 2)
Drive Type (See all supported drives)
  • 3.5" SATA HDD
  • 2.5" SATA SSD
Hot Swappable Drive*
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
RJ-45 1GbE LAN Port 4
RJ-45 10GbE LAN Port 2
USB 3.2 Gen 1 Port 2
Expansion Port 2
Expansion Port Type Infiniband
PCIe
PCIe
PCIe Expansion 2 x Gen3 x8 slots (x8 link)
Appearance
Appearance
Form Factor (RU) 2U
Size (Height x Width x Depth) 88 mm x 482 mm x 724 mm
Weight 14.5 kg
Rack Installation Support* 4-post 19" rack (Synology Rail Kit - RKS-02)
Notes The rail kit is sold separately
Others
Others
System Fan 80 mm x 80 mm x 4 pcs
Fan Speed Mode
  • Full-Speed Mode
  • Cool Mode
  • Quiet Mode
Easy Replacement System Fan
Power Recovery
Noise Level* 50.2 dB(A)
Scheduled Power On / Off
Wake on LAN / WAN
Power Supply Unit / Adapter 500 watts
550 watts*
Redundant Power Supply
AC Input Power Voltage 100 V to 240 V AC
Power Frequency 50/60 Hz, Single Phase
Power Consumption* 142.5 watts (Access)
72.76 watts (HDD Hibernation)
British Thermal Unit 485.93 BTU/hr (Access)
248.11 BTU/hr (HDD Hibernation)
Notes
  • For more information on how power consumption is measured, refer to this article.
  • Power supply specifications vary by hardware revision. A 500 W PSU is used in devices with serial numbers containing SZR (5th to 7th digits), while a 550 W PSU is in devices with UUR and VR1 serial numbers. For more information, refer to the Product Change Notice.
  • 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
Temperature
Operating Temperature 0°C to 35°C (32°F to 95°F)
Storage Temperature -20°C to 60°C (-5°F to 140°F)
Operating Humidity 8% to 80% RH
Storage Humidity 5% to 95% RH
Certification
Certification
  • FCC
  • CE
  • BSMI
  • VCCI
  • RCM
  • EAC
  • CCC
  • KC
  • BIS
  • UL
Warranty
Warranty
5 Years
Notes The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
Environment
Environment
RoHS Compliant
Packaging Content
Packaging Content
  • Main Unit X 1
  • Accessory Pack X 1
  • AC Power Cord X 2
  • Quick Installation Guide X 1
Optional Accessories
Optional Accessories
  • DDR4 ECC UDIMM: D4EC-2666-8G/D4EC-2666-16G
  • Expansion Units: RX1217/RX1217RP
  • Enterprise Series 3.5" SATA HDD: HAT5300 Series
  • Enterprise Series 2.5" SATA SSD: SAT5200 Series
  • M.2 SSD & 10GbE Combo Adapter Card: E10M20-T1
  • M.2 SSD Adapter Card: M2D20
  • 25GbE Network Interface Card: E25G30-F2
  • 10GbE Network Interface Card: E10G30-F2/E10G30-T2/E10G18-T1
  • Rail Kit Sliding: RKS-02
Notes All memory modules will operate at the maximum frequency specified by the CPU manufacturer.
DSM Specifications
Storage Management
Storage Management
Maximum Single Volume Size
  • 1 PB (64 GB memory required, for RAID 6 groups only)
  • 200 TB (32 GB memory required)
  • 108 TB
Maximum Internal Volume Number 256
SSD Read/Write Cache (Determining cache size)
SSD TRIM
RAID Group
Supported RAID Type
  • RAID F1
  • 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
  • RAID F1
  • RAID 1
  • RAID 5
  • RAID 6
  • RAID 10
Volume Expansion by Adding a HDD
  • RAID F1
  • JBOD
  • RAID 5
  • RAID 6
Global Hot Spare Supported RAID Type
  • RAID F1
  • RAID 1
  • RAID 5
  • RAID 6
  • RAID 10
Notes
  • Volumes over 108 TB require 32 GB of memory or more.
  • Actual maximum storage pool and volume sizes depend on drive sizes used, the number of drive bays available, and the RAID configuration.
  • Usable capacity for each volume will be lower than the maximum volume size and is dependent on the filesystem and the amount of system metadata stored.
  • When Peta Volume is enabled, validated services and packages are required. Please refer to this article for more information on limitations.
File System
File System
Internal Drives
  • Btrfs
  • ext4
External Drives
  • Btrfs
  • ext4
  • ext3
  • FAT32
  • NTFS
  • HFS+
  • exFAT
File Services
File Services
File Protocol
  • SMB
  • AFP
  • NFS
  • FTP
  • WebDAV
  • Rsync
Maximum Number of SMB Connections (FSCT-Based) 1,300
Windows Access Control List (ACL) Integration
NFS Kerberos Authentication
Notes
  • Connection value of this model is tested with Synology SATA SSD fully populated and up to four 10GbE network ports
  • Models with expandable memory are tested with the maximum supported quantity installed.
  • SMB performance was evaluated using Microsoft File Server Capacity Tool (FSCT) version 1.3, with the following configuration:
    • Test workload: HomeFolder scenario provided by the FSCT tool
    • Test duration: 600 seconds
    • Domain controller & FSCT controller: Windows Server 2022
    • FSCT clients: 8 × Windows 10 machines
    • SMB feature: Directory leasing enabled
Account & Shared Folder
Account & Shared Folder
Maximum Local User Accounts 5,120
Maximum Local Groups 512
Maximum Shared Folder 512
Maximum Shared Folder Sync Tasks 32
Hybrid Share
Hybrid Share
Maximum Hybrid Share Folders 15
Hyper Backup
Hyper Backup
Folder and Package Backup
Entire System Backup
Notes Full-system backup requires DSM 7.2 or later.
High Availability
High Availability
Synology High Availability
Log Center
Log Center
Log Center
Syslog Events per Second 3,000
Virtualization
Virtualization
VMware vSphere ESXi 8.0 U2, ESXi 8.0 U1, ESXi 8.0, ESXi 7.0 U3, ESXi 7.0 U2, ESXi 7.0 U1, ESXi 7.0, ESXi 6.7 U3, ESXi 6.7 U2, ESXi 6.7 U1, ESXi 6.7, ESXi 6.5 U3, ESXi 6.5 U2, ESXi 6.5 U1, ESXi 6.5
Microsoft Hyper-V Windows Server 2022, Windows Server 2019, Windows Server 2016
Citrix XenServer XenServer 8, Citrix Hypervisor 8.2 LTSR CU1
OpenStack Cinder
General Specifications
General Specifications
Supported Protocols SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, Fibre Channel, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV
Supported Browsers
  • Chrome
  • Firefox
  • Edge
  • Safari
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
Notes For an updated list of supported browser versions, check the DSM Technical Specifications.
Add-on Packages view the complete package list
Central Management System
Central Management System
Synology AI Console
Synology AI Console
Synology AI Console
Third-Party AI Model Integration
Maximum De-Identification Rate 1,300 words per second
Notes
  • De-identification performance measurement: Filters for Credit Card Numbers, IBAN, Individual Taxpayer Identification Number, SSN, and Names applied to a 4,355-word English text.
  • To enable de-identification, your device must have at least 8 GB of memory and Container Manager installed.
Synology Chat
Synology Chat
Synology Chat
Maximum Number of Users 500
Notes
  • Measured with simulated users, each with an average record of 20,000 messages, emojis, or stickers. The required server response time is below ten seconds.
  • Models with expandable memory are tested with the maximum supported quantity installed.
Download Station
Download Station
Download Station
Maximum Concurrent Download Tasks 80
SAN Manager
SAN Manager
SAN Manager
Maximum iSCSI Target Number 128
Maximum LUN 256
LUN Clone/Snapshot, Windows ODX
Synology MailPlus / MailPlus Server
Synology MailPlus / MailPlus Server
Synology MailPlus / MailPlus Server
Free Email Accounts 5 (Additional accounts require purchase of licenses)
Maximum Number of Users 2,800
Notes
  • The suggested maximum number of users is based on the following workload: 20% of users with a 20,000 item mailbox randomly performing actions and receiving 240 emails per day, and 80% of users receiving 20 emails per day. Learn more
  • Models with SSD support are tested with a single SSD volume.
  • Models with expandable memory are tested with the maximum supported quantity installed. Learn more about memory requirements.
  • Operating in high-availability mode will incur additional overhead.
  • Features enabled during evaluation: anti-spam, anti-virus, DNSBL, greylist, content scanning, and full-text search (English).
Media Server
Media Server
Media Server
DLNA Compliance
Synology Photos
Synology Photos
Synology Photos
Facial Recognition
Object Recognition
Snapshot Replication
Snapshot Replication
Snapshot Replication
Maximum Snapshots per Shared Folder 512
Maximum Snapshots per LUN 128
Maximum Snapshots per System 16,384
Maximum Replication Tasks for Shared Folders 64
Maximum Replication Tasks for LUNs 32
Maximum Replication Tasks per System 64
Surveillance Station
Surveillance Station
Surveillance Station
Default Licenses 2 (Additional cameras require purchase of licenses)
Maximum IP Cameras and Total FPS (H.264)
  • 1080p: 90 channels, 2250 FPS
  • 3M: 90 channels, 1500 FPS
  • 5M: 90 channels, 900 FPS
  • 4K: 55 channels, 550 FPS
Maximum IP Cameras and Total FPS (H.265)
  • 1080p: 90 channels, 2700 FPS
  • 3M: 90 channels, 2250 FPS
  • 5M: 90 channels, 1500 FPS
  • 4K: 90 channels, 1080 FPS
Notes
  • Performance figures are obtained from testing conducted with the device fully populated with drives, with their default memory configuration, and under a continuous recording setup. Actual system capabilities may vary based on configuration, drive performance, enabled features, and the presence of additional workloads.
  • Use NVR Selector to quickly find a suitable model based on your requirements.
  • The number of video channels that can be viewed simultaneously is double the maximum number of cameras for the same codec and resolution.
Synology Drive
Synology Drive
Synology Drive
Maximum Number of Users 2,400
Maximum Number of Hosted Files 15,000,000 (applies to files indexed or hosted by Synology Drive. For file access through other standard protocols, refer to the File Services section above)
Notes
  • The suggested maximum number of users is based on the following workload: 20% of users randomly perform file operations (upload, download, move, and delete), and 80% of users are logged in but idle. Learn more
  • Models with SSD support are tested with a single SSD volume.
  • Models with expandable memory are tested with the maximum supported quantity installed.
  • Exceeding the recommended numbers above will not block application operations, but may result in longer response time.
  • Btrfs file system and non-encrypted shared folders were used during the aforementioned testing.
Synology Office
Synology Office
Synology Office
Maximum Number of Users 2,300
Notes
  • The suggested maximum number of users is based on the following workload: 20% of users are executing random actions at an average of 30-second intervals, and 80% of users are logged in and viewing a file. Learn more
  • Models with SSD support are tested with a single SSD volume.
  • Models with expandable memory are tested with the maximum supported quantity installed.
  • Client performance may affect maximum simultaneous editing users. Client PCs used for testing: Intel Core i3-3220 / 8GB RAM
Virtual Machine Manager
Virtual Machine Manager
Virtual Machine Manager
Recommended Virtual Machine Instances 16 (Learn more)
Recommended Virtual DSM Number (Licenses required) 16 (including 1 Free License)
Notes The specifications vary depending on system configuration and memory size.
VPN Server
VPN Server
VPN Server
Maximum Connections 32
Notes: Model specifications are subject to change without prior notice. 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. The actual performance may be lower than lab testing figure due to differences in server configuration, deployment, and the number of active operations. If usage requirements exceed the specifications above, please contact our regional partners for professional advice.
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