CPU

• Intel Xeon D-1541 8-core (16-thread) 2.1 GHz, Turbo Boost up to 2.7 GHz

Hardware encryption engine

• Yes (AES-NI)

Memory

• 16 GB DDR4 ECC UDIMM (expandable up to 64 GB)
• Genuine Synology memory modules must be installed to ensure system compatibility and reliability

Compatible drive types

• 16 x 3.5" or 2.5" SATA HDD/SSD (drives not included)
• Only drives listed on the compatibility list can be used to create storage pools
• Only Synology SAT5200 2.5" or Synology SNV3500 series SSDs (sold separately) can be used to create SSD caches

Hot swappable drive

• Yes

External ports

• 2 x USB 3.2 Gen 1 ports
• 2 x Expansion ports (Infinite band)

Form factor

• Rackmount 3U

Size (HxWxD)

• 132.3 x 482 x 656.5 mm (with server handles)

Weight

• 17.4 kg

LAN ports

• 4 x 1GbE RJ45
• 2 x 10GbE RJ45

Wake on LAN/WAN

• Yes

PCIe 3.0 slots

• 2 x 8-lane x8 slots
• Supports network interface cards and M.2 NVMe SSD adapter cards for SSD cache

Scheduled power on/off

• Yes

System fans

• 3 x (80 x 80 x 32 mm)

AC input power voltage

• 100 V to 240 V AC

Power frequency

• 50/60 Hz, single phase

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

Maximum operating altitude

• 5,000 m (16,400 ft)

General DSM Specification

Networking protocols

• SMB, AFP, NFS, FTP, WebDAV, CalDAV, iSCSI, Telnet, SSH, SNMP, VPN (PPTP, OpenVPN, L2TP)

File systems

• Internal: Btrfs, ext4
• External: Btrfs, ext4, ext3, FAT32, NTFS, HFS+, exFAT

Supported RAID types

• Synology RAID F1, Basic, JBOD, RAID 0, RAID 1, RAID 5, RAID 6, RAID 10

Storage management

• Maximum single volume size: 108/200 TB
• Maximum system snapshots: 65,536
• Maximum internal volumes: 256

SSD cache

• Read/write cache support
• 2.5" SATA SSD support
• M.2 NVMe SSD support

File sharing capabilities

• Maximum local user accounts: 16,000
• Maximum local groups: 512
• Maximum shared folders: 512
• Maximum concurrent SMB/NFS/AFP/FTP connections: 4,000

Privileges

• Windows Access Control List (ACL), application privileges

Directory services

• Connects with Windows AD/LDAP servers enabling domain users to login via SMB/NFS/AFP/FTP/File Station using their existing credentials.

Virtualizations

• VMware vSphere 6.5, Microsoft Hyper-V, Citrix, OpenStack

Security

• Firewall, shared folder encryption, SMB encryption, FTP over SSL/TLS, SFTP, rsync over SSH, login auto block, Let's Encrypt support, HTTPS (customizable cipher suite)

Supported clients

• Windows 7 onwards, macOS 10.12 onwards

Supported browsers

• Chrome, Firefox, Edge, Internet Explorer 10 onwards, Safari 10 onwards, Safari (iOS 10 onwards), Chrome (Android 6.0 onwards) on tablets

Package contents

• 1 x Synology RS4021xs+ enclosure
• 1 x Quick Installation Guide
• 1 x Accessory pack
• 2 x AC power cords