FlashStation FS6400

Performance Compatibility Downloads Compare

Business advice

Performance Compatibility Downloads Compare

Business advice

FlashStation FS6400

Blazingly-fast all-flash server aiming for I/O-intensive applications

Features
Specs

Uncompromising performance

Synology FlashStation FS6400 is a 2U rackmount server designed for I/O-intensive and latency-sensitive tasks, ideal for multimedia post-production, virtual machines, online transaction processing, or database applications.

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CPU

Dual Intel^® Xeon^® Silver 8-core with NUMA

Memory

DDR4 ECC RDIMM, up to 512GB

High Performance

Over 240,000 iSCSI 4K random write IOPS

Scalability

Up to 72 drives with FX2421

Fast and reliable networking

With multi-LAN design, FS6400 is capable of performing Link Aggregation and failover. For environments requiring a higher speed, two optional Ethernet add-in cards can be installed on PCIe 3.0 slots to provide fast data transmission.

Complete iSCSI and virtualization solutions

Synology iSCSI storage supports most virtualization solutions such as VMware vSphere, Microsoft Hyper-V, Citrix Xen Server, and OpenStack Cinder to enhance work efficiency. You can run and manage multiple virtual machines on Windows, Linux, or DSM using Virtual Machine Manager. Learn more

Next-generation file system for better data protection

The Btrfs file system introduces advanced storage technologies and optimized snapshots to prevent data corruption and reduce maintenance overheads. It offers flexible, efficient data protection and recovery tools while ensuring high-level data integrity. Learn more

Flexible Shared Folder/User Quota System provides comprehensive quota control on all user accounts and shared folders
Snapshot Replication provides schedulable and storage capacity-saving data protection with 1,024 shared folder backups and 65,000 system-wide snapshots
File- or folder-level data restoration accelerates data recovery and provides more flexibility for businesses
Automatic file self-healing detects and recovers corrupted files without user intervention

Next-generation file system for better data protection

RAID F1

Due to the peculiarities of SSD and RAID technology, a common challenge lies in how to prevent all of the drives from failing at the same time because of the evenly distributed workload. RAID F1 alleviates this problem with a specially designed algorithm to unevenly distribute workload to drives, enhancing the resilience of the storage pool and ensuring your data remains safe.

See the white paper for more technical details regarding RAID F1

Compared with traditional RAID, RAID F1 distributes uneven workload to SSDs to prevent all drives from wearing out simultaneously.

Flash volume deduplication

Remove duplicate data on all-flash arrays with volume-wide deduplication to greatly increase storage efficiency. Eliminate redundant data to save up to 65% in storage space use in applications like virtual desktop infrastructure, and virtual machine.

Digital asset protection

Powered by Synology DiskStation Manager (DSM), Synology NAS offers advanced security measures to protect against sudden data loss and potential security holes. Learn more

Security Advisor

Analyze system settings, password strength and network preferences, and remove any possible malware.

AppArmor

A kernel-level enhancement that blocks malicious programs from accessing unauthorized system resources.

AES 256-bit encryption

Encrypt shared folders and network data transmission to avoid unauthorized data access.

2-step verification

Prevent others from logging in to your DSM by generating a six-digit one-time password (OTP) on your mobile device.

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.

Powered by Synology DiskStation Manager

Synology High Availability

Seamless transition between clustered servers in the event of a server failure to minimize the impact on applications.

Learn more

Synology Office

Collaborate on documents, spreadsheets, and slides in real time to boost team productivity.

Learn more

Synology MailPlus

Secure, reliable, and private mail server solution with an intuitive and modern mail client.

Learn more

Virtual Machine Manager

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

Learn more

Security

Secure data with comprehensive built-in security tools to protect your devices against evolving threats.

Learn more

Snapshot Replication

Schedulable and instantaneous data protection for shared folders and iSCSI LUNs for disaster prevention.

Learn more

Performance backed by Synology drives

Engineered to handle high-intensity workloads, Synology hard drives consistently deliver top-grade performance.

Enterprise Series 2.5" SATA

Hardware Overview

1Power button and indicator
2Beep off button
3Drive tray
4Drive status indicator

5PSU fan
6Power port
7PSU indicator
8Console port

9Reset button
101GbE RJ-45 port
1110GbE RJ-45 (10GBASE-T) port
12USB 3.0 port

13PCIe expansion slot
14Expansion port

Notes:

FS6400 supports up to two optional expansion units, which can be either two identical RX1217sas/FX2421 or one of each.
Flash volume deduplication is available on flash-only volumes comprised of compatible Synology SSD. Synology measured a data reduction ratio of over 3.15:1 based on 10 VMs configured for remote desktop with two operating systems and enterprise applications installed.
Storage drives are sold separately. Refer to the compatibility list for compatible devices.

Hardware Specifications
CPU
CPU	CPU Model	Intel Xeon Silver 4110
	CPU Quantity	2
	CPU Core	8
	CPU Architecture	64-bit
	CPU Frequency	2.1 (base) / 3.0 (turbo) GHz
	Hardware Encryption Engine
Memory
Memory	System Memory	32 GB DDR4 ECC RDIMM
	Memory Module Pre-installed	32 GB (16 GB x 2)
	Total Memory Slots	16
	Maximum Memory Capacity	512 GB (32 GB x 16)
	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 more information on the recommended memory configurations, visit here.
Storage
Storage	Drive Bays	24
	Maximum Drive Bays with Expansion Unit	72 (FX2421 x 2)
	Compatible Drive Type* (See all supported drives)	2.5" SAS HDD 2.5" SAS SSD 2.5" SATA SSD
	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.
External Ports
External Ports	RJ-45 1GbE LAN Port	2
	RJ-45 10GbE LAN Port	2
	USB 3.2 Gen 1 Port*	2
	Expansion Port	1
	Expansion Port Type	Mini-SAS HD
	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	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	17.26 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*	53.7 dB(A)
	Scheduled Power On / Off
	Wake on LAN / WAN
	Power Supply Unit / Adapter	800 watts
	Redundant Power Supply
	AC Input Power Voltage	100V to 240V AC
	Power Frequency	50/60 Hz, Single Phase
	Power Consumption	288.49 watts (Access) 145.8 watts (HDD Hibernation)
	British Thermal Unit	984.37 BTU/hr (Access) 497.49 BTU/hr (HDD Hibernation)
	Notes	Power consumption is measured when it is fully loaded with HGST 1.8TB HUC101818CS4204 hard drive(s). Noise Level Testing Environment: Fully loaded with Toshiba 600GB AL14SEB060N 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)
	Relative Humidity	5% to 95% RH
Certification
Certification	FCC CE BSMI VCCI RCM UKCA EAC CCC KC
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 RDIMM: D4RD-2666-16G/D4RD-2666-32G Expansion Units: FX2421/RX1222sas/RX1217sas Enterprise Series 2.5" SATA SSD: SAT5200 Series 25GbE Network Interface Card: E25G30-F2 10GbE Network Interface Card: E10G21-F2/E10G30-T2/E10G18-T1 Rail Kit Sliding: RKS-02
	Notes	It is required to use D4RD-2666-16G with identical memory modules of the same capacity and frequency. For more information, visit here. Expansion Unit FX2421 can only be used with identical expansion units.

DSM Specifications
Storage Management
Storage Management	Maximum Single Volume Size	1 PB (64 GB memory required, for RAID 6 groups only) 200 TB 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	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. Actual maximum storage pool and volume sizes depend on drive sizes used, the number of drive bays available, and the RAID configuration.
File System
File System	Internal Drives	Btrfs ext4
	External Drives	Btrfs ext4 ext3 FAT NTFS HFS+ exFAT
	Notes	exFAT Access can be installed for free from Package Center in DSM 7.0. In DSM 6.2 or earlier versions, exFAT Access needs to be purchased in Package Center.
File Services
File Services	File Protocol	SMB AFP NFS FTP WebDAV Rsync
	Maximum Concurrent SMB/AFP/FTP Connections	8,000
	Maximum Concurrent SMB/AFP/FTP Connections (with RAM expansion)	10,000
	Windows Access Control List (ACL) Integration
	NFS Kerberos Authentication
	Notes	Regarding data concerning tests with RAM expansion, all memory slots are installed with the maximum capacity of supported RAM. During testing, the maximum number of SSDs supported by this model is installed in a RAID 5 configuration. The testing standard was based on the maximum number of concurrent connections supported by this model. During the testing, 25% of the connections were used to transfer files concurrently. The transfer process guaranteed that the connections were not interrupted; the minimum transfer speed was not guaranteed.
Account & Shared Folder
Account & Shared Folder	Maximum Local User Accounts	16,000
	Maximum Local Groups	512
	Maximum Shared Folder	512
	Maximum Shared Folder Sync Tasks	32
Hybrid Share
Hybrid Share	Hybrid Share Folder Number	30
Hyper Backup
Hyper Backup	Data & Folder 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
	Syslog Events per Second	3,000
Virtualization
Virtualization	VMware ESXi 6.5 and VAAI
	Windows Server 2016
	Windows Server 2019
	Windows Server 2022
	Citrix Ready
	OpenStack
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 Chat
Synology Chat
	Suggested Users	1,500
	Notes	Models with expandable memory are tested with their maximum supported memory.
SAN Manager
SAN Manager
	Maximum iSCSI Target Number	256
	Maximum LUN	512
	LUN Clone/Snapshot, Windows ODX
	Notes	iSCSI Manager has been renamed to SAN Manager in DSM 7.0.
Synology MailPlus / MailPlus Server
Synology MailPlus / MailPlus Server
	Free Email Accounts	5 (Additional accounts require purchase of licenses)
	Suggested Users	17,500
	Maximum Server Performance	5,721,000 emails per day, approx. 174GB
	Notes	FS series were installed with 12 SSDs in RAID F1 configuration. Suggested users is derived from testing in an environment with 20% heavy users (each with 20,000 pre-populated emails and receiving 240 emails per day) and 80% light users (each receiving an average of 20 emails per day). Learn more Models with expandable memory are tested with their maximum supported memory. The performance of the mail system will slightly decrease in high-availability mode due to data synchronization between the two servers. Functions that were enabled in all of the tests above: anti-spam, anti-virus, DNSBL, greylist, content scan, full-text search (English only).
Snapshot Replication
Snapshot Replication
	Maximum Snapshots per Shared Folder	1,024
	Maximum of System Snapshots	65,536
Surveillance Station
Surveillance Station
	Default Licenses	2 (Additional cameras require purchase of licenses)
	Suggested Maximum IP Cameras and Total FPS (H.264)	720p: 520 channels, 15600 FPS 1080p: 485 channels, 4850 FPS 3M: 450 channels, 4500 FPS 5M: 380 channels, 3800 FPS 4K: 220 channels, 2200 FPS
	Suggested Maximum IP Cameras and Total FPS (H.265)	720p: 550 channels, 16500 FPS 1080p: 520 channels, 15600 FPS 3M: 485 channels, 4850 FPS 5M: 450 channels, 4500 FPS 4K: 380 channels, 3800 FPS
	Notes	Surveillance Station 9.1.3 or above is required to support the maximum IP cameras and FPS figures listed. 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 maximum number of camera stream outputs is 2 times the suggested maximum number of IP cameras.
Synology Drive
Synology Drive
	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)
	Recommended Number of Hosted Files	100,000,000 (applies to files indexed or hosted by Synology Drive. For file access through other standard protocols, refer to the File Services section above)
	Notes	Exceeding the recommended numbers above will not block application operations, but may result in longer response time. Utilizing SSD cache can significantly improve performance. Models with expandable memory are tested with their maximum supported memory. Btrfs file system and non-encrypted shared folders were used during the aforementioned testing.
Synology Office
Synology Office
	Suggested Users	16,250
	Notes	Suggested users is derived from testing in an environment with 60% idle users (each logging in and viewing documents) and 40% active users (each executing random actions at intervals of 20 to 40 seconds) operating within documents, each document having 30 users. Learn more Models with expandable memory are tested with their maximum supported memory. 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
	Recommended Virtual Machine Instances	32 (Learn more)
	Recommended Virtual DSM Number (Licenses required)	32 (including 1 Free License)
	Notes	The specifications vary depending on system configuration and memory size.
VPN Server
VPN Server
	Maximum Connections	60

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.