Synology RS4021xs+ |

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Synology BLACK FRIDAY / CYBER MONDAY DEALS
Synology Black Friday Deals (2025)
Synology Black Friday Deals (2025)
Black Friday 2025 Deals - Data Storage from Synology, UGREEN, QNAP, WD, Seagate, UniFi, Terramaster
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UK 4.68 OFF (WAS 384) [LINK] Synology - DDR4 - module - 16 GB - DIMM 288-pin - 2666 MHz / PC4-21300 - 1.2 V - Amazon
UK 10 OFF (WAS 380) [LINK] Synology DiskStation DS423 4 Bay Desktop NAS Enclosure Amazon
UK 5.02 OFF (WAS 380) [LINK] SYNOLOGY Diskstation DS725+ Amazon
UK 66.94 OFF (WAS 446) [LINK] Synology - DDR4 - module - 32 GB - DIMM 288-pin - 2666 MHz / PC4-21300 - 1.2 V - Amazon
UK 181.78 OFF (WAS 640) [LINK] Synology DS223J 8TB 2 Bay NAS Solution installed with 2 x 4TB Western Digital Re Amazon
UK 29.64 OFF (WAS 501) [LINK] Synology Disk Station DS620slim - NAS server - 6 bays - SATA 6Gb/s - RAID 0, 1, Amazon
UK 12.66 OFF (WAS 521) [LINK] Synology DS223 8TB 2 Bay Desktop NAS Solution installed with 2 x 4TB Seagate Iro Amazon
UK 36.07 OFF (WAS 550) [LINK] Synology DS223 8TB 2 Bay Desktop NAS Solution installed with 2 x 4TB Western Dig Amazon
UK 37.72 OFF (WAS 571) [LINK] Synology 4 bay NAS 1.4Ghz Quadcore CPU - RS422+ Rack Station, Black Amazon
UK 9 OFF (WAS 609) [LINK] Synology DVA1622 Deep Learning NVR Surveillance System 2-Bay Amazon
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UK 49.62 OFF (WAS 725) [LINK] Synology DS224+ 2-Bay Diskstation NAS (Intel Celeron J4125 4-Core 2.0 GHz 2GB DD Amazon
UK 39.29 OFF (WAS 738) [LINK] Synology 4-Bay RackStation RS822RP+ (Diskless) Amazon
UK 18.66 OFF (WAS 1290) [LINK] Synology RS1221RP+8 bay NAS 2.4Ghz Quadcore CPU Amazon
UK 8.63 OFF (WAS 1450) [LINK] Synology DS1823xs+ 8 Bay NAS Desktop: High-Performance Storage Solution Amazon
UK 60.26 OFF (WAS 1929) [LINK] Synology RS2423+ 12 Bay Rack NAS Storage Solution Amazon
UK 9.49 OFF (WAS 2041) [LINK] Synology SA3400D NAS/storage server Rack (2U) Ethernet LAN D-1541 Amazon
UK 160.52 OFF (WAS 3446) [LINK] Synology RackStation RS1221+ NAS Rack (2U) Ethernet LAN Black V1500B Amazon
UK 78.7 OFF (WAS 7870) [LINK] Synology 2-Bay NAS DS223 (Diskless) Amazon
USA 10 OFF (WAS 285) [LINK] Sparepart: Synology PSU Redundant Power Module 550W, Applied Models: FS3410, W12 Amazon
USA 320.11 OFF (WAS 807) [LINK] Synology RackStation RS1221+ - NAS Server - 8 Bays - Rack-mountable - SATA 6Gb/s Amazon
USA 73.89 OFF (WAS 1552) [LINK] Synology 12 Bay FlashStation FS2500 (Diskless) Amazon
USA 4.64 OFF (WAS 3395) [LINK] Synology 12-Bay Rackmount NAS SA3610 (Diskless) Amazon
USA 5.24 OFF (WAS 9120) [LINK] MORE DEALS HERE
ON YOUTUBE
Getting latest videos with a keyword: RS4021xs+
RELATED POSTS
Synology RS3621XS+, RS4021XS+ and RS3621RPxs Specifications Revealed
Synology RS3621xs+, RS362RP1xs and RS4021xs+ NAS Coming Soon
PERFORMANCE:
| Specs | Measure | RS4021xs+ |
|---|---|---|
| 10GbE iSCSI Random IOPS 4KB | Read IOPS/Write IOPS | 289854 / 146487 |
| 1GbE Web Server PHP Response Efficiency | Responses per second | 116633 |
| Aggregated 10GbE SMB Random IOPS 4KB | Write IOPS/Read IOPS | 153385 / 234698 |
| Aggregated 10GbE SMB Sequential Throughput 64KB | Read MBs/Write MBs | 6259 / 3135 |
| Aggregated 10GbE SMB Sequential Throughput via Encrypted Shared Folder 64KB | Write MBs/Read MBs | 2149 / 4144 |
| Specs | RS4021xs+ |
Specification:
| Specs | Value |
|---|---|
| CPU-Model | Intel Xeon D-1541 |
| CPU Architecture | 64-bit |
| CPU Frequency | 8-core 2.1 (base) / 2.7 (turbo) GHz |
| Hardware Encryption Engine (AES-NI) | |
| 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 | The specifications vary depending on system configuration and memory size. |
| Drive Bays | 16 |
| Maximum Drive Bays with Expansion Unit | 40 (RX1217/RX1217RP x 2) |
| Maximum Single Volume Size* |
|
| Hot Swappable Drive | |
| 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 |
| PCIe Expansion | 2 x Gen3 x8 slots (x8 link) |
| Internal Drives |
|
| External Drives |
|
| Form-Factor | 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) |
| System Fan | 80 mm x 80 mm x 3 pcs |
| Fan Speed Mode |
|
| Easy Replacement System Fan | |
| Power Recovery | |
| Noise Level* | 44.7 dB(A) |
| Scheduled Power On / Off | |
| Wake on LAN / WAN | |
| 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) |
| 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 |
|
| Warranty | 5 Years |
| Environment | RoHS Compliant |
| Packaging Content |
|
| Optional Accessories |
|
| Maximum Internal Volume Number | 256 |
| SSD Read / Write Cache (White Paper) | |
| SSD TRIM | |
| RAID Group | |
| Supported RAID Type |
|
| RAID Migration |
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| Volume Expansion with Larger HDDs |
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| Volume Expansion by Adding a HDD |
|
| Global Hot Spare Supported RAID Type |
|
| File Protocol | CIFS/AFP/NFS/FTP/WebDAV |
| Maximum Concurrent CIFS/AFP/FTP Connections | 4,000 |
| Windows Access Control List (ACL) Integration | |
| NFS Kerberos Authentication | |
| Maximum Local User Accounts | 16,000 |
| Maximum Local Groups | 512 |
| Maximum Shared Folder | 512 |
| Maximum Shared Folder Sync Tasks | 32 |
| Synology High Availability | |
| Log Center | |
| Syslog Events per Second | 3,000 |
| VMware vSphere with VAAI | |
| Windows Server 2016 | |
| Windows Server 2019 | |
| Citrix Ready | |
| OpenStack | |
| Networking Protocols | SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV |
| Supported Browsers |
|
| 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 |
| Antivirus by McAfee (Trial) | |
| Central Management System | |
| Synology Chat | |
| Maximum Users | 3,000 |
| Document Viewer | |
| Download Station | |
| Maximum Concurrent Download Tasks | 80 |
| exFAT Access (Optional) | |
| Maximum iSCSI Target Number | 256 |
| Maximum iSCSI LUN | 512 |
| iSCSI LUN Clone/Snapshot, Windows ODX | |
| Synology MailPlus / MailPlus Server | |
| Free Email Accounts | 5 (Licenses required for additional accounts) |
| Maximum Number of Concurrent Users | 1,100 |
| Maximum Server Performance | 4,312,000 emails per day, approx. 131GB |
| 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) | 90 (including 2 Free License) (See All Supported IP Cameras) |
| Total FPS (H.264) |
2700 FPS @ 720p (1280x720) 2250 FPS @ 1080p (1920x1080) 1500 FPS @ 3M (2048x1536) 900 FPS @ 5M (2591x1944) 550 FPS @ 4K (3840x2160) |
| Total FPS (H.265) |
2700 FPS @ 720p (1280x720) 2700 FPS @ 1080p (1920x1080) 2250 FPS @ 3M (2048x1536) 1500 FPS @ 5M (2591x1944) 1080 FPS @ 4K (3840x2160) |
| Synology Drive | |
| Recommended Number of Hosted Files | 5,000,000 (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 | 2,000 (the number of connections that can be maintained when the recommended number of hosted files was reached) |
| Synology Office | |
| Video Station | |
| Virtual Machine Manager | |
| Recommended Virtual Machine Instances | 16 (Learn more) |
| VPN Server | |
| Maximum Connections | 40 |
| Specs | Value |
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