Synology Inc.

Highlight Differences

FS2500

Hardware Specifications
CPU
CPU Model	AMD Ryzen V1780B	Intel Xeon D-1531
CPU Quantity	1	1
CPU Core	4	6
CPU Architecture	64-bit	64-bit
CPU Frequency	3.35 (base) / 3.6 (turbo) GHz	2.2 (base) / 2.7 (turbo) GHz
Hardware Encryption Engine
Memory
System Memory	8 GB DDR4 ECC UDIMM	8 GB DDR4 ECC UDIMM
Memory Module Pre-installed	8 GB (8 GB x 1)	8 GB (8 GB x 1)
Total Memory Slots	2	4
Maximum Memory Capacity	32 GB (16 GB x 2)	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.	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
Drive Bays	12	12
Maximum Drive Bays with Expansion Unit		36 (RX1217 x 2)
Drive Type (See all supported drives)	2.5" SATA SSD	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.	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
RJ-45 1GbE LAN Port	2	4
RJ-45 10GbE LAN Port	2
USB 3.2 Gen 1 Port	2	2
Expansion Port		2
Expansion Port Type		Infiniband
Notes	MTU value of 1GbE LAN port has a limit of 1500.
PCIe
PCIe Expansion	1 x Gen3 x8 slot (x4 link)	2 x Gen3 x8 slots (x8 link)
Appearance
Form Factor (RU)	1U	2U
Size (Height x Width x Depth)	44 mm x 481.9 mm x 555.9 mm	88 mm x 482 mm x 724 mm
Weight	8.3 kg	14.5 kg
Rack Installation Support*	4-post 19" rack (Synology Rail Kit - RKS-01)	4-post 19" rack (Synology Rail Kit - RKS-02)
Notes	The rail kit is sold separately	The rail kit is sold separately
Others
System Fan	40 mm x 40 mm x 4 pcs	80 mm x 80 mm x 4 pcs
Fan Speed Mode	Full-Speed Mode Cool Mode Quiet Mode	Full-Speed Mode Cool Mode Quiet Mode
Easy Replacement System Fan
Power Recovery
Noise Level*	57.6 dB(A)	50.2 dB(A)
Scheduled Power On / Off
Wake on LAN / WAN
Power Supply Unit / Adapter	350 watts	500 watts 550 watts*
Redundant Power Supply
AC Input Power Voltage	100V to 240V AC	100 V to 240 V AC
Power Frequency	50/60 Hz, Single Phase	50/60 Hz, Single Phase
Power Consumption*	74.83 watts (Access)	140.01 watts (Access) 65.94 watts (HDD Hibernation)
British Thermal Unit	255.17 BTU/hr (Access)	477.43 BTU/hr (Access) 224.86 BTU/hr (HDD Hibernation)
Notes	For more information on how power consumption is measured, refer to this article. Noise testing was conducted with the Synology system fully installed with Synology SATA SSDs and in an idle state. Two G.R.A.S. type 40AE microphones were placed at a 1 m distance from the front and rear of the device. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%.	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 SYR (5th to 7th digits), while a 550 W PSU is in devices with UTR and VR2 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
Operating Temperature	0°C to 35°C (32°F to 95°F)	0°C to 35°C (32°F to 95°F)
Storage Temperature	-20°C to 60°C (-5°F to 140°F)	-20°C to 60°C (-5°F to 140°F)
Operating Humidity	8% to 80% RH	8% to 80% RH
Storage Humidity	5% to 95% RH	5% to 95% RH
Certification	FCC CE BSMI VCCI RCM UKCA EAC KC UL	FCC CE BSMI VCCI RCM EAC CCC KC BIS UL
Warranty	5 Years	5 Years
Notes	The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)	The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
Environment	RoHS Compliant	RoHS Compliant
Packaging Content	Main Unit X 1 Accessory Pack X 1 AC Power Cord X 2 Quick Installation Guide X 1	Main Unit X 1 Accessory Pack X 1 AC Power Cord X 2 Quick Installation Guide X 1
Optional Accessories	DDR4 ECC UDIMM: D4EU01-8G/D4EU02-16G Enterprise Series 2.5" SATA SSD: SAT5200 Series 25GbE Network Interface Card: E25G30-F2 10GbE Network Interface Card: E10G30-F2/E10G30-T2/E10G18-T1 Rail Kit Sliding: RKS-01	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	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.	All memory modules will operate at the maximum frequency specified by the CPU manufacturer.

DSM Specifications
Storage Management
Maximum Single Volume Size	200 TB (32 GB memory required) 108 TB	1 PB (64 GB memory required, for RAID 6 groups only) 200 TB (32 GB memory required) 108 TB
Maximum Internal Volume Number	256	128
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 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	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	RAID F1 RAID 1 RAID 5 RAID 6 RAID 10
Volume Expansion by Adding a HDD	RAID F1 JBOD RAID 5 RAID 6	RAID F1 JBOD RAID 5 RAID 6
Global Hot Spare Supported RAID Type	RAID F1 RAID 1 RAID 5 RAID 6 RAID 10	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.	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
Internal Drives	Btrfs ext4	Btrfs ext4
External Drives	Btrfs ext4 ext3 FAT32 NTFS HFS+ exFAT	Btrfs ext4 ext3 FAT32 NTFS HFS+ exFAT
File Services
File Protocol	SMB AFP NFS FTP WebDAV Rsync	SMB AFP NFS FTP WebDAV Rsync
Maximum Number of SMB Connections (FSCT-Based)	700	1,000
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	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
Maximum Local User Accounts	2,048	5,120
Maximum Local Groups	512	512
Maximum Shared Folder	512	512
Maximum Shared Folder Sync Tasks	12	16
Hybrid Share
Hybrid Share Folder Number	15	15
Hyper Backup
Data & Folder Backup
Entire System Backup
Notes	Full-system backup requires DSM 7.2 or later.	Full-system backup requires DSM 7.2 or later.
High Availability
Synology High Availability
Log Center
Syslog Events per Second	3,000	3,000
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	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 2022, Windows Server 2019, Windows Server 2016
Citrix XenServer	XenServer 8, Citrix Hypervisor 8.2 LTSR CU1	XenServer 8, Citrix Hypervisor 8.2 LTSR CU1
OpenStack	Cinder	Cinder
General Specifications
Supported Protocols	SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, Fibre Channel, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV	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	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	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.	For an updated list of supported browser versions, check the DSM Technical Specifications.

Add-on Packages (view the complete package list)
Central Management System
Synology AI Console
Third-Party AI Model Integration
Maximum De-Identification Rate	700 words per second	1,000 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.	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
Maximum Number of Users	300	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.	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
Maximum Concurrent Download Tasks		80
SAN Manager
Maximum iSCSI Target Number	64	128
Maximum LUN	128	256
LUN Clone/Snapshot, Windows ODX
Synology MailPlus / MailPlus Server
Free Email Accounts	5 (Additional accounts require purchase of licenses)	5 (Additional accounts require purchase of licenses)
Maximum Number of Users	1,600	2,200
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).	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
DLNA Compliance
Synology Photos
Facial Recognition
Object Recognition
Snapshot Replication
Maximum Snapshots per Shared Folder	256	512
Maximum Snapshots per LUN	64	128
Maximum Snapshots per System	4,096	16,384
Maximum Replication Tasks for Shared Folders	32	64
Maximum Replication Tasks for LUNs	16	32
Maximum Replication Tasks per System	32	64
Surveillance Station
Default Licenses	2 (Additional cameras require purchase of licenses)	2 (Additional cameras require purchase of licenses)
Maximum IP Cameras and Total FPS (H.264)	1080p: 100 channels, 2800 FPS 3M: 100 channels, 1200 FPS 5M: 70 channels, 700 FPS 4K: 50 channels, 500 FPS	1080p: 75 channels, 2100 FPS 3M: 75 channels, 1500 FPS 5M: 75 channels, 900 FPS 4K: 55 channels, 550 FPS
Maximum IP Cameras and Total FPS (H.265)	1080p: 100 channels, 3000 FPS 3M: 100 channels, 2400 FPS 5M: 100 channels, 1300 FPS 4K: 80 channels, 800 FPS	1080p: 75 channels, 2250 FPS 3M: 75 channels, 2250 FPS 5M: 75 channels, 1500 FPS 4K: 75 channels, 900 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.	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
Maximum Number of Users	1,300	1,900
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)	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.	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
Maximum Number of Users	1,300	1,900
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	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
Recommended Virtual Machine Instances	8 (Learn more)	12 (Learn more)
Recommended Virtual DSM Number (Licenses required)	8 (including 1 Free License)	12 (including 1 Free License)
Notes	The specifications vary depending on system configuration and memory size.	The specifications vary depending on system configuration and memory size.
VPN Server
Maximum Connections	12	16

Hardware Specs

Hardware Specifications

CPU

CPU Model

FS2500	AMD Ryzen V1780B
RS3621RPxs	Intel Xeon D-1531

CPU Quantity

FS2500	1
RS3621RPxs	1

CPU Core

FS2500	4
RS3621RPxs	6

CPU Architecture

FS2500	64-bit
RS3621RPxs	64-bit

CPU Frequency

FS2500	3.35 (base) / 3.6 (turbo) GHz
RS3621RPxs	2.2 (base) / 2.7 (turbo) GHz

Hardware Encryption Engine

Memory

System Memory

FS2500	8 GB DDR4 ECC UDIMM
RS3621RPxs	8 GB DDR4 ECC UDIMM

Memory Module Pre-installed

FS2500	8 GB (8 GB x 1)
RS3621RPxs	8 GB (8 GB x 1)

Total Memory Slots

FS2500	2
RS3621RPxs	4

Maximum Memory Capacity

FS2500	32 GB (16 GB x 2)
RS3621RPxs	64 GB (16 GB x 4)

Notes

FS2500	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.
RS3621RPxs	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.

FS2500

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.

RS3621RPxs

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

Drive Bays

FS2500	12
RS3621RPxs	12

Maximum Drive Bays with Expansion Unit

Drive Type (See all supported drives)

FS2500	2.5" SATA SSD
RS3621RPxs	3.5" SATA HDD 2.5" SATA SSD

Hot Swappable Drive*

Notes

FS2500	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.
RS3621RPxs	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

RJ-45 1GbE LAN Port

FS2500	2
RS3621RPxs	4

RJ-45 10GbE LAN Port

FS2500	2
RS3621RPxs

USB 3.2 Gen 1 Port

FS2500	2
RS3621RPxs	2

Expansion Port

Expansion Port Type

Notes

FS2500	MTU value of 1GbE LAN port has a limit of 1500.
RS3621RPxs

PCIe

PCIe Expansion

FS2500	1 x Gen3 x8 slot (x4 link)
RS3621RPxs	2 x Gen3 x8 slots (x8 link)

Appearance

Form Factor (RU)

FS2500	1U
RS3621RPxs	2U

Size (Height x Width x Depth)

FS2500	44 mm x 481.9 mm x 555.9 mm
RS3621RPxs	88 mm x 482 mm x 724 mm

Weight

FS2500	8.3 kg
RS3621RPxs	14.5 kg

Rack Installation Support*

FS2500	4-post 19" rack (Synology Rail Kit - RKS-01)
RS3621RPxs	4-post 19" rack (Synology Rail Kit - RKS-02)

Notes

FS2500	The rail kit is sold separately
RS3621RPxs	The rail kit is sold separately

Others

System Fan

FS2500	40 mm x 40 mm x 4 pcs
RS3621RPxs	80 mm x 80 mm x 4 pcs

Fan Speed Mode

FS2500	Full-Speed Mode Cool Mode Quiet Mode
RS3621RPxs	Full-Speed Mode Cool Mode Quiet Mode

Easy Replacement System Fan

Power Recovery

Noise Level*

FS2500	57.6 dB(A)
RS3621RPxs	50.2 dB(A)

Scheduled Power On / Off

Wake on LAN / WAN

Power Supply Unit / Adapter

FS2500	350 watts
RS3621RPxs	500 watts 550 watts*

Redundant Power Supply

AC Input Power Voltage

FS2500	100V to 240V AC
RS3621RPxs	100 V to 240 V AC

Power Frequency

FS2500	50/60 Hz, Single Phase
RS3621RPxs	50/60 Hz, Single Phase

Power Consumption*

FS2500	74.83 watts (Access)
RS3621RPxs	140.01 watts (Access) 65.94 watts (HDD Hibernation)

British Thermal Unit

FS2500	255.17 BTU/hr (Access)
RS3621RPxs	477.43 BTU/hr (Access) 224.86 BTU/hr (HDD Hibernation)

Notes

FS2500	For more information on how power consumption is measured, refer to this article. Noise testing was conducted with the Synology system fully installed with Synology SATA SSDs and in an idle state. Two G.R.A.S. type 40AE microphones were placed at a 1 m distance from the front and rear of the device. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%.
RS3621RPxs	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 SYR (5th to 7th digits), while a 550 W PSU is in devices with UTR and VR2 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%

FS2500

For more information on how power consumption is measured, refer to this article.
Noise testing was conducted with the Synology system fully installed with Synology SATA SSDs and in an idle state. Two G.R.A.S. type 40AE microphones were placed at a 1 m distance from the front and rear of the device. Background noise: 16.49-17.51 dB(A); Temperature: 24.25-25.75˚C; Humidity: 58.2-61.8%.

RS3621RPxs

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 SYR (5th to 7th digits), while a 550 W PSU is in devices with UTR and VR2 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

Operating Temperature

FS2500	0°C to 35°C (32°F to 95°F)
RS3621RPxs	0°C to 35°C (32°F to 95°F)

Storage Temperature

Operating Humidity

Storage Humidity

Certification

Warranty

FS2500	5 Years
RS3621RPxs	5 Years

Notes

FS2500	The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)
RS3621RPxs	The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more)

Environment

Packaging Content

FS2500	Main Unit X 1 Accessory Pack X 1 AC Power Cord X 2 Quick Installation Guide X 1
RS3621RPxs	Main Unit X 1 Accessory Pack X 1 AC Power Cord X 2 Quick Installation Guide X 1

Optional Accessories

FS2500	DDR4 ECC UDIMM: D4EU01-8G/D4EU02-16G Enterprise Series 2.5" SATA SSD: SAT5200 Series 25GbE Network Interface Card: E25G30-F2 10GbE Network Interface Card: E10G30-F2/E10G30-T2/E10G18-T1 Rail Kit Sliding: RKS-01
RS3621RPxs	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

FS2500	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.
RS3621RPxs	All memory modules will operate at the maximum frequency specified by the CPU manufacturer.

Software Specs

DSM Specifications

Storage Management

Maximum Single Volume Size

FS2500	200 TB (32 GB memory required) 108 TB
RS3621RPxs	1 PB (64 GB memory required, for RAID 6 groups only) 200 TB (32 GB memory required) 108 TB

Maximum Internal Volume Number

SSD Read/Write Cache (Determining cache size)

SSD TRIM

RAID Group

Supported RAID Type

FS2500	RAID F1 Basic JBOD RAID 0 RAID 1 RAID 5 RAID 6 RAID 10
RS3621RPxs	RAID F1 Basic JBOD RAID 0 RAID 1 RAID 5 RAID 6 RAID 10

RAID Migration

FS2500	Basic to RAID 1 Basic to RAID 5 RAID 1 to RAID 5 RAID 5 to RAID 6
RS3621RPxs	Basic to RAID 1 Basic to RAID 5 RAID 1 to RAID 5 RAID 5 to RAID 6

Volume Expansion with Larger HDDs

Volume Expansion by Adding a HDD

Global Hot Spare Supported RAID Type

Notes

FS2500

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.

RS3621RPxs

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

Internal Drives

External Drives

File Services

File Protocol

Maximum Number of SMB Connections (FSCT-Based)

Windows Access Control List (ACL) Integration

NFS Kerberos Authentication

Notes

FS2500

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

RS3621RPxs

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

Maximum Local User Accounts

Maximum Local Groups

Maximum Shared Folder

Maximum Shared Folder Sync Tasks

Hybrid Share

Hyper Backup

Data & Folder Backup

Entire System Backup

Notes

FS2500	Full-system backup requires DSM 7.2 or later.
RS3621RPxs	Full-system backup requires DSM 7.2 or later.

High Availability

Synology High Availability

Log Center

FS2500
RS3621RPxs

Syslog Events per Second

Virtualization

VMware vSphere

FS2500	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
RS3621RPxs	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

FS2500	Windows Server 2022
RS3621RPxs	Windows Server 2022, Windows Server 2019, Windows Server 2016

Citrix XenServer

FS2500	XenServer 8, Citrix Hypervisor 8.2 LTSR CU1
RS3621RPxs	XenServer 8, Citrix Hypervisor 8.2 LTSR CU1

OpenStack

General Specifications

Supported Protocols

FS2500	SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, Fibre Channel, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV
RS3621RPxs	SMB1 (CIFS), SMB2, SMB3, NFSv3, NFSv4, NFSv4.1, NFS Kerberized sessions, iSCSI, Fibre Channel, HTTP, HTTPs, FTP, SNMP, LDAP, CalDAV

Supported Browsers

Supported Language

FS2500	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
RS3621RPxs	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

FS2500	For an updated list of supported browser versions, check the DSM Technical Specifications.
RS3621RPxs	For an updated list of supported browser versions, check the DSM Technical Specifications.

Add-on Packages (view the complete package list)

Central Management System

Synology AI Console

FS2500
RS3621RPxs

Third-Party AI Model Integration

Maximum De-Identification Rate

Notes

FS2500	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.
RS3621RPxs	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

FS2500
RS3621RPxs

Maximum Number of Users

Notes

FS2500	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.
RS3621RPxs	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

FS2500
RS3621RPxs

Maximum Concurrent Download Tasks

SAN Manager

FS2500
RS3621RPxs

Maximum iSCSI Target Number

Maximum LUN

LUN Clone/Snapshot, Windows ODX

Synology MailPlus / MailPlus Server

FS2500
RS3621RPxs

Free Email Accounts

FS2500	5 (Additional accounts require purchase of licenses)
RS3621RPxs	5 (Additional accounts require purchase of licenses)

Maximum Number of Users

Notes

FS2500

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).

RS3621RPxs

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

FS2500
RS3621RPxs

DLNA Compliance

Synology Photos

FS2500
RS3621RPxs

Facial Recognition

Object Recognition

Snapshot Replication

FS2500
RS3621RPxs

Maximum Snapshots per Shared Folder

Maximum Snapshots per LUN

Maximum Snapshots per System

Maximum Replication Tasks for Shared Folders

Maximum Replication Tasks for LUNs

Maximum Replication Tasks per System

Surveillance Station

FS2500
RS3621RPxs

Default Licenses

FS2500	2 (Additional cameras require purchase of licenses)
RS3621RPxs	2 (Additional cameras require purchase of licenses)

Maximum IP Cameras and Total FPS (H.264)

FS2500	1080p: 100 channels, 2800 FPS 3M: 100 channels, 1200 FPS 5M: 70 channels, 700 FPS 4K: 50 channels, 500 FPS
RS3621RPxs	1080p: 75 channels, 2100 FPS 3M: 75 channels, 1500 FPS 5M: 75 channels, 900 FPS 4K: 55 channels, 550 FPS

Maximum IP Cameras and Total FPS (H.265)

FS2500	1080p: 100 channels, 3000 FPS 3M: 100 channels, 2400 FPS 5M: 100 channels, 1300 FPS 4K: 80 channels, 800 FPS
RS3621RPxs	1080p: 75 channels, 2250 FPS 3M: 75 channels, 2250 FPS 5M: 75 channels, 1500 FPS 4K: 75 channels, 900 FPS

Notes

FS2500

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.

RS3621RPxs

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

FS2500
RS3621RPxs

Maximum Number of Users

Maximum Number of Hosted Files

FS2500	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)
RS3621RPxs	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

FS2500

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.

RS3621RPxs

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

FS2500
RS3621RPxs

Maximum Number of Users

Notes

FS2500

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

RS3621RPxs

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

FS2500
RS3621RPxs

Recommended Virtual Machine Instances

Recommended Virtual DSM Number (Licenses required)

Notes

FS2500	The specifications vary depending on system configuration and memory size.
RS3621RPxs	The specifications vary depending on system configuration and memory size.

VPN Server

FS2500
RS3621RPxs

Maximum Connections