Synology RackStation RS4021xs+ NAS Rack (3U) Ethernet LAN Black D-1541

SKU
RS4021XS+/256T/16X16T
Login for pricing
256 TB, 3U, Intel Xeon D-1541 (8x 2.1GHz), 16GB DDR4, 16x 2.5"/3.5", 2x USB 3.2 Gen1, 4x 1GbE RJ-45, 2x 10GbE RJ-45
  • Intel® Xeon® D-1541 8-core 2.1 GHz
  • Built-in dual-port 10GbE
  • 16 GB ECC DDR4 Up to 64 GB
  • Up to 40 drive bays with RX1217(RP)
More Information
Type NAS
Processor Intel Xeon D
Ethernet ports 6
Storage drives installed Yes
SKU RS4021XS+/256T/16X16T
Manufacturer Synology
Availability In Stock
Product Family RackStation
Securing your business assets
The 16-bay RS4021xs+ provides solid data security and lightening-fast performance with over 234K 4K random read IOPS and 6,258 MB/s sequential read throughput1. Together with its 8-core processor, ECC memory, advanced snapshot technology, and built-in 10GbE connectivity, the RS4021xs+ can support large multi-user environments while handling data-intensive workloads.

Engineered for service continuity
The RS4021xs+ ensures mission-critical data is always available, enabling businesses to deliver the best results, even in the face of disaster.

Redundant power
Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can 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.

Next-generation file system
Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots

Customize to your business
The RS4021xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment2.

Double bandwidth
Upgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.

SSD cache3
Boost 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 expansion
Quickly and easily scale up to 40 drives with two RX1217(RP) expansion units.

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. Deduplication4, integrity checks, and incremental transfer technology reduce bandwidth and storage used.

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.

Storage for virtualization
Synology 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

All-in-one surveillance solution
Synology Surveillance Station transforms the RS4021xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras5 and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios.

Secure and private
AES-256 encryption keeps locally-stored footage secure.

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.
Storage
Total installed storage capacity256 TB
Online RAID migrationYes
Online RAID expansionYes
Storage drives installedYes
Installed storage drive typeHDD
Number of storage drives installed16
Supported storage drive typesHDD & SSD
Number of storage drives supported16
Storage drive interfaceSerial ATA III
Storage drive capacity16 TB
Storage drive size3.5"
Hot-swap drive baysYes
RAID supportYes
Supported file systemsBTRFS, FAT32, HFS+, NTFS, exFAT, ext3, ext4
RAID levels0, 1, 5, 6, 10, F1, JBOD
HDD speed7200 RPM
Supported storage drive interfacesSerial ATA II, Serial ATA III
Storage drive sizes supported2.5,3.5"
Processor
Processor manufacturerIntel
Processor threads16
Processor cache12 MB
Processor boost frequency2.7 GHz
CPU configuration (max)1
Conflict-Free processorYes
Processor frequency2.1 GHz
Processor familyIntel® Xeon® D
Processor modelD-1541
Processor cores8
Memory
Internal memory typeDDR4
Internal memory16 GB
Memory clock speed2666 MHz
Maximum RAM supported64 GB
Memory slots4
Memory form factorUDIMM
ECCYes
Network
Link aggregationYes
Ethernet LAN data rate supported (max)10000 Mbit/s
Ethernet LANYes
Ethernet LAN data rates10,100,1000,10000 Mbit/s
Wake-on-LAN readyYes
Supported network protocolsSMB, AFP, NFS, FTP, WebDAV, CalDAV, iSCSI, Telnet, SSH, SNMP, VPN
iSCSI supportYes
Ports & interfaces
USB portYes
USB 3.2 Gen 1 (3.1 Gen 1) Type-A ports quantity2
PCI Express x8 (Gen 3.x) slots2
Ethernet LAN (RJ-45) ports6
Hard drive
RAID supportYes
Supported file systemsBTRFS, FAT32, HFS+, NTFS, exFAT, ext3, ext4
RAID levels0, 1, 5, 6, 10, F1, JBOD
HDD speed7200 RPM
Design
Cooling typeActive
Fan diameter8 cm
Product colourBlack
Number of fans3 fan(s)
LED indicatorsYes
Chassis typeRack (3U)
Technical details
TypeNAS
Device classSmall & Medium Business
Backup functionYes
Backup featuresCloud, iSCSI LUN
Product colourBlack
Number of users16000 user(s)
Noise level44.7 dB
Multilingual supportYes
LED indicatorsYes
Chassis typeRack (3U)
BuzzerYes
Number of fans3 fan(s)
Sustainability complianceYes
Sustainability certificatesUL ECOLOGO
Compliance certificatesCE, RoHS
Performance
Built-in FTP serverYes
System logYes
Share folderCIFS/AFP/NFS/FTP/WebDAV
Browser supportedChrome, Firefox, Edge, Internet Explorer, Safari
TypeNAS
Device classSmall & Medium Business
Backup functionYes
Backup featuresCloud, iSCSI LUN
On/off switchYes
Windows operating systems supportedYes
Mac operating systems supportedYes
Security algorithms256-bit AES, HTTPS, SSH, SSL/TLS
Reset buttonYes
Operating system installedDiskStation Manager
Number of users16000 user(s)
Noise level44.7 dB
Multilingual supportYes
BuzzerYes
Access Control List (ACL)Yes
Third-party supportYes
SnapshotYes
Cooling
Cooling typeActive
Fan diameter8 cm
Number of fans3 fan(s)
Security
Security algorithms256-bit AES, HTTPS, SSH, SSL/TLS
Access Control List (ACL)Yes
Software
Windows operating systems supportedYes
Mac operating systems supportedYes
Operating system installedDiskStation Manager
Management features
On/off switchYes
Reset buttonYes
Power
Power consumption (HDD standby)62.68 W
Power supply locationBuilt-in
Power supply unit (PSU) capacity800 W
AC input voltage100 - 240 V
AC input frequency50 - 60 Hz
Redundant power supply (RPS) supportYes
Power consumption (typical)145.79 W
Weight & dimensions
Width482 mm
Depth656.5 mm
Height132.3 mm
Packaging content
Cables includedAC
Power cables quantity2
Processor special features
Intel VT-x with Extended Page Tables (EPT)Yes
Intel Virtualization Technology for Directed I/O (VT-d)Yes
Intel Virtualization Technology (VT-x)Yes
Intel TSX-NI version1.00
Intel TSX-NIYes
Intel Trusted Execution TechnologyYes
Intel Secure Key Technology version1.00
Intel Enhanced Halt StateYes
Intel 64Yes
Idle StatesYes
Execute Disable BitYes
Enhanced Intel SpeedStep TechnologyYes
Embedded options availableNo
System requirements
Windows operating systems supportedYes
Mac operating systems supportedYes
Operational conditions
Storage temperature (T-T)-20 - 60 °C
Storage relative humidity (H-H)5 - 95%
Operating temperature (T-T)0 - 35 °C
Operating relative humidity (H-H)5 - 95%
Operating altitude0 - 5000 m
Certificates
CertificationFCC, BSMI, VCCI, RCM, EAC, CCC, KC
Packaging data
Cables includedAC

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SKU
RS4021XS+/256T/16X16T
HD6500
RS2821RP+/256TB-HAT5300
RS4021XS+/192T/16X12T
K/RS4021XS+_+16X_HAT5300-12T
K/RS4021XS+_+16X_HAT5300-16T
Description
Securing your business assets
The 16-bay RS4021xs+ provides solid data security and lightening-fast performance with over 234K 4K random read IOPS and 6,258 MB/s sequential read throughput1. Together with its 8-core processor, ECC memory, advanced snapshot technology, and built-in 10GbE connectivity, the RS4021xs+ can support large multi-user environments while handling data-intensive workloads.

Engineered for service continuity
The RS4021xs+ ensures mission-critical data is always available, enabling businesses to deliver the best results, even in the face of disaster.

Redundant power
Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can 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.

Next-generation file system
Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots

Customize to your business
The RS4021xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment2.

Double bandwidth
Upgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.

SSD cache3
Boost 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 expansion
Quickly and easily scale up to 40 drives with two RX1217(RP) expansion units.

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. Deduplication4, integrity checks, and incremental transfer technology reduce bandwidth and storage used.

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.

Storage for virtualization
Synology 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

All-in-one surveillance solution
Synology Surveillance Station transforms the RS4021xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras5 and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios.

Secure and private
AES-256 encryption keeps locally-stored footage secure.

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.
All the space you will ever need
With 60 bays in a 4U rackmount enclosure and support for up to 300 drives after expansion, the Synology HD6500 is the ideal high-density storage solution for large-scale warm and cold storage applications such as full system backups, video post-production, and large surveillance deployments.

Consistent performance at five times the size
The HD6500 is designed to scale up to 5 times in capacity with four additional RX6022sas expansion units. SAS multipath-enabled connectivity provides up to double the typical performance together and increased redundancy.

Built for high reliability
The HD6500 is built to keep mission-critical data and services accessible, so that businesses can continue to perform even when disaster strikes.

Out-of-band (OOB) management
Simplify troubleshooting by managing powered-down devices remotely and accessing critical logs through a dedicated interface.

Dual power supply
Reduce the possibility of power disruptions on a single distribution channel or PDU adversely impacting data and service availability with redundant PSUs.

High-reliability expansion architecture
Redundant SAS links prevent single points of failure from affecting other expansion units, ensuring higher data and service availability.

Powerful networking options
The HD6500 supports a large variety of networking interfaces, protocols, and configurations, whether you need fast sequential transfer, support for simultaneous connections, or high network redundancy.

Built-in fast connectivity
Three Gigabit Ethernet and two 10GbE RJ-45 ports allow for rapid transfer speeds right out of the box.

Mix and match network ports
Add extra 10GbE SFP+/RJ-45, 25GbE SFP28, or Fibre Channel ports in varying configurations by leveraging the four expansion slots.2

Failover and network balancing
Bond multiple network interfaces with Link Aggregation to enable automatic network failover and load balancing.

Consolidate your data storage
Back up your backup solutions, bring all your files together in one place, or bring distributed surveillance deployments under central control.

Massive file server
Host and retrieve massive files from extensive archives whenever needed. Provide user friendly access and set up powerful cross-site syncing.

Central backup server
Protect large numbers of PCs, servers, Synology systems, and hypervisors, or back up your backup servers with a central storage solution.

Main surveillance storage
Manage distributed deployments of hundreds of local recording servers and thousands of IP cameras centrally.

Get more with DiskStation Manager
Take advantage of a host of native productivity, management, and security solutions available in the web-based Synology DSM operating system.
Versatile and scalable storage
Synology RS2821RP+ is a 3U 16-bay storage server designed to accommodate a diverse set of business requirements. Scalable to 28 drives, the unit provides powerful backup and restoration functionality for the SMB sector. It delivers 2,200 MB/s sequential read and 105K 4K random read performance, and can be upgraded with SSD cache and 10/25Gb Ethernet options.

High performance storage for anything
Over 105K/59K random read/write IOPS and up to 2,220/1,164 MB/s sequential read/write throughput ensure ample performance for demanding workloads.

Built for reliability
Redundant power
Reduce the possibility of power disruptions on a single distribution channel or PDU adversely impacting data and service availability.

Near-zero downtime
Pair two identical devices with Synology High Availability and enable automatic minute-level failover between both devices in the event one server fails.

Data integrity and protection
ECC memory prevents data corruption, while the Btrfs file system brings higher reliability, snapshot technology, and simplified data protection.

Customize to suit
Easily adapt the RS2821RP+ to any business environment by adding faster networking, local SSD cache, or storage capacity.
10/25GbE ready
Support for 10/25GbE NICs lets you boost server throughput up to five times using Link Aggregation (bonding).
SSD cache
Boost read/write IOPS over HDD-only arrays by up to 16 times or more with NVMe or SATA
On-demand drive bays
Expand to 28 drive bays with one RX1217(RP) expansion unit

License-free backup solutions
Hyper Backup
Back up files, iSCSI LUNs, installed applications, and system configurations to destinations including Synology C2 Storage, public cloud platforms, USB devices, file servers, local folders, or other Synology NAS.
Set and forget backup tasks with regular schedules, enhance security with fine-grained user permissions and encryption, keep backup sizes small with built-in deduplication, and restore data flexibly with multi-versioning.

Snapshot Replication
Snapshot Replication enables flexible point-in-time snapshots of shared folders, and virtual machines with an RPO as low as 5 minutes and recovery within seconds.

Active Backup Suite
Securely back up Windows clients and servers, Microsoft 365 and Google Workspace accounts, file servers, and VMware and Hyper-V virtual machines with the Active Backup Suite.
Leverage built-in deduplication technology to reduce backup sizes and multi-versioning to allow flexible restoration.

Serving remote workforces
Keep your remote workforce connected with powerful out-of-the-box solutions for collaboration, file sharing, and communication.

Synology Drive
Host your own private cloud behind the safety of your NAS with 100% data ownership and no subscription fees.

Synology Office
Create documents, spreadsheets, and slides in a multi-user environment. Real-time collaboration and automatic saving make remote work sessions a breeze.

Synology Chat
Chat and collaborate with colleagues using secure end-to-end encryption on with mobile, desktop, and browser clients.

Storage for virtualization
DSM streamlines provisioning for and management of virtual machines with full certification for VMware® vSphere™, Microsoft® Hyper-V®, Citrix® XenServer™, and OpenStack virtualization environments.
Synology Storage Console for VMware or Windows platforms lets you manage storage directly from your hypervisor. VMware VAAI integration and Windows ODX help offload storage operations and speed up data transfer.

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

Powered by Synology DiskStation Manager
The web-based DiskStation Manager (DSM) operating system supports a host of native productivity and management solutions.
Central Management System
Conveniently manage your fleet of Synology NAS from a centralized console.
Synology Drive
Instantly access your NAS files across multiple devices whenever you want, wherever you are.
Collaboration Suite
Satisfy all team collaboration needs behind the safety of your own private cloud with Synology Office, Calendar, and Chat.
Virtual Machine Manager
Run various operating systems in isolated sandboxes. Seamlessly clone, store, and migrate virtual machines.
Security
Shield your Synology NAS from the most sophisticated threats with industry-leading security solutions.
Surveillance
Protect your home or business with intelligent monitoring and video management tools.
Securing your business assets
The 16-bay RS4021xs+ provides solid data security and lightening-fast performance with over 234K 4K random read IOPS and 6,258 MB/s sequential read throughput1. Together with its 8-core processor, ECC memory, advanced snapshot technology, and built-in 10GbE connectivity, the RS4021xs+ can support large multi-user environments while handling data-intensive workloads.

Engineered for service continuity
The RS4021xs+ ensures mission-critical data is always available, enabling businesses to deliver the best results, even in the face of disaster.

Redundant power
Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can 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.

Next-generation file system
Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots

Customize to your business
The RS4021xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment2.

Double bandwidth
Upgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.

SSD cache3
Boost 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 expansion
Quickly and easily scale up to 40 drives with two RX1217(RP) expansion units.

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. Deduplication4, integrity checks, and incremental transfer technology reduce bandwidth and storage used.

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.

Storage for virtualization
Synology 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

All-in-one surveillance solution
Synology Surveillance Station transforms the RS4021xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras5 and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios.

Secure and private
AES-256 encryption keeps locally-stored footage secure.

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.
Securing your business assets
The 16-bay RS4021xs+ provides solid data security and lightening-fast performance with over 234K 4K random read IOPS and 6,258 MB/s sequential read throughput1. Together with its 8-core processor, ECC memory, advanced snapshot technology, and built-in 10GbE connectivity, the RS4021xs+ can support large multi-user environments while handling data-intensive workloads.

Engineered for service continuity
The RS4021xs+ ensures mission-critical data is always available, enabling businesses to deliver the best results, even in the face of disaster.

Redundant power
Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can 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.

Next-generation file system
Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots

Customize to your business
The RS4021xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment2.

Double bandwidth
Upgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.

SSD cache3
Boost 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 expansion
Quickly and easily scale up to 40 drives with two RX1217(RP) expansion units.

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. Deduplication4, integrity checks, and incremental transfer technology reduce bandwidth and storage used.

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.

Storage for virtualization
Synology 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

All-in-one surveillance solution
Synology Surveillance Station transforms the RS4021xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras5 and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios.

Secure and private
AES-256 encryption keeps locally-stored footage secure.

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.
Securing your business assets
The 16-bay RS4021xs+ provides solid data security and lightening-fast performance with over 234K 4K random read IOPS and 6,258 MB/s sequential read throughput1. Together with its 8-core processor, ECC memory, advanced snapshot technology, and built-in 10GbE connectivity, the RS4021xs+ can support large multi-user environments while handling data-intensive workloads.

Engineered for service continuity
The RS4021xs+ ensures mission-critical data is always available, enabling businesses to deliver the best results, even in the face of disaster.

Redundant power
Dual PSUs provide protection against a PSU failure or accidental cord removal while hot-swappable fans can 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.

Next-generation file system
Btrfs prevents data corruption and reduces maintenance overheads with advanced storage technologies and optimized snapshots

Customize to your business
The RS4021xs+ includes two PCIe slots for performance, networking, and storage upgrades enabling it to adapt to any business environment2.

Double bandwidth
Upgrade network bandwidth in minutes by 2x or more with Synology’s range of 10GbE NICs.

SSD cache3
Boost 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 expansion
Quickly and easily scale up to 40 drives with two RX1217(RP) expansion units.

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. Deduplication4, integrity checks, and incremental transfer technology reduce bandwidth and storage used.

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.

Storage for virtualization
Synology 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

All-in-one surveillance solution
Synology Surveillance Station transforms the RS4021xs+ into a feature-packed Network Video Recorder solution. Support for up to 90 IP cameras5 and video analytics such as motion detection, no idle zone, foreign object detection, and anomaly detection cater to the most common surveillance scenarios.

Secure and private
AES-256 encryption keeps locally-stored footage secure.

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.
Short Description
256 TB, 3U, Intel Xeon D-1541 (8x 2.1GHz), 16GB DDR4, 16x 2.5"/3.5", 2x USB 3.2 Gen1, 4x 1GbE RJ-45, 2x 10GbE RJ-45
High Density HD6500, 2 x Intel Xeon Silver 4210R 10-core, 64 GB DDR4 ECC RDIMM, 60 x 3.5" SAS HDD, Rackmount 4U
256TB, 3U, AMD Ryzen V1500B (4x 2.2GHz), 4GB DDR4, 16x 2.5"/3.5" SATA, 4x RJ-45, 2x USB 3.2 Gen1
192 TB, 3U, Intel Xeon D-1541 (8x 2.1GHz), 16GB DDR4, 16x 2.5"/3.5", 2x USB 3.2 Gen1, 4x 1GbE RJ-45, 2x 10GbE RJ-45
192 TB, 3U, Intel Xeon D-1541 (8x 2.1GHz), 16GB DDR4, 16x 2.5"/3.5", 2x USB 3.2 Gen1, 4x 1GbE RJ-45, 2x 10GbE RJ-45
256 TB, 3U, Intel Xeon D-1541 (8x 2.1GHz), 16GB DDR4, 16x 2.5"/3.5", 2x USB 3.2 Gen1, 4x 1GbE RJ-45, 2x 10GbE RJ-45
Manufacturer
Synology
Synology
Synology
Synology
Synology
Synology