Overview:RackStationRS4021xs+ Enterprise NAS with built-in service continuity engineered for data-intensive applications.
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 throughput . 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.
Features: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 environment .
- Double bandwidth Upgrade network bandwidth in minutes by 2x or more with Synologys range of 10GbE NICs.
- SSD cache 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.
The ultimate backup solutions - license-free - Keep disaster at bay
- Backup your entire IT infrastructure
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.
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 cameras 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.
Powered by Synology DiskStation Manager The RS4021xs+ runs Synology DiskStation Manager (DSM), the web-based operating system equipped with powerful applications and services for business.
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.
Public Cloud Integration Back up and synchronize data easily between public cloud accounts and your NAS.
Specifications:
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Specifications |
| Product Code | Synology RS4021xs+ |
| CPU |
| CPU Model | Intel Xeon D-1541 |
| CPU Quantity | 1 |
| CPU Architecture | 64-bit |
| CPU Frequency | 8-core 2.1 (base) / 2.7 (turbo) GHz |
| Hardware Encryption Engine (AES-NI) | Yes |
| Memory |
| System Memory | 16 GB DDR4 ECC UDIMM |
| Memory Module Pre-installed | 16 GB (16 GB x 1) |
| Total Memory Slots | 4 |
| Maximum Memory Capacity | 64 GB (16 GB x 4) |
| 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 | 16 |
| Maximum Drive Bays with Expansion Unit | 40 (RX1217/RX1217RP x 2) |
| Compatible Drive Type* (See all supported drives) | 3.5" SATA HDD |
| 2.5" SATA SSD |
| Maximum Single Volume Size | 200 TB (32 GB memory required) |
| 108 TB |
| Hot Swappable Drive | Yes |
| Notes | It is strongly recommended that you only install drives listed on your device's compatibility list. Storage pool and volume creation processes may fail when using unverified drives. Synology is unable to provide technical support for devices using unsupported components. |
| "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 108 TB (with memory less than 32 GB) or 200 TB (with memory equal to or greater than 32 GB). |
| External Ports |
| RJ-45 1GbE LAN Port | 4 (with Link Aggregation / Failover support) |
| RJ-45 10GbE LAN Port | 2 (with Link Aggregation / Failover support) |
| USB 3.2 Gen 1 Port | 2 |
| Expansion Port | 2 |
| Notes | The USB 3.0 standard was renamed to USB 3.2 Gen 1 by the USB Implementers Forum (USB-IF) in 2019. |
| PCIe |
| PCIe Expansion | 2 x Gen3 x8 slots (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 |
| Form Factor (RU) | 3U |
| Size (Height x Width x Depth) | 132.3 mm x 482 mm x 656.5 mm |
| Weight | 17.4 kg |
| Rack Installation Support | 4-post 19" rack (Synology Rail Kit - RKS1317) |
| Notes | The rail kit is sold separately |
| Others |
| System Fan | 80 mm x 80 mm x 3 pcs |
| Fan Speed Mode | Full-Speed Mode |
| Cool Mode |
| Quiet Mode |
| Easy Replacement System Fan | Yes |
| Power Recovery | Yes |
| Noise Level | 44.7 dB(A) |
| Scheduled Power On / Off | Yes |
| Wake on LAN / WAN | Yes |
| Power Supply Unit / Adapter | 800 W |
| Redundant Power Supply |
| AC Input Power Voltage | 100 V to 240 V AC |
| Power Frequency | 50/60 Hz, Single Phase |
| Power Consumption | 145.79 W (Access) |
| 62.68 W (HDD Hibernation) |
| British Thermal Unit | 497.14 BTU/hr (Access) |
| 213.74 BTU/hr (HDD Hibernation) |
| Notes | Power consumption is measured when it is fully loaded with Synology 8TB HAT5300-8T 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 35°C (32°F to 95°F) |
| Storage Temperature | -20°C to 60°C (-5°F to 140°F) |
| Relative Humidity | 5% to 95% RH |
| Certification |
| Certification | FCC |
| CE |
| BSMI |
| VCCI |
| RCM |
| EAC |
| CCC |
| KC |
| UL |
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