Synology SA3400D 12-Bay Active-Passive NAS Enclosure with Dual Controllers
Keep services online with efficient high-availability storage
High-availability file and block storage solution

Accessible and convenient
Maintain data availability with an active-passive high availability dual-controller module

Versatile applications
Manage, distribute, and protect data, back up endpoints, and guard physical premises

Fast and efficient
Over 3,500/2,900 MB/s seq. read/write throughput1 and over 500 TB maximum storage capacity2
Built-in High Availability
Keep file sharing services, block storage, backups, and other office applications online with automatic minute-level failover. Defend against operational disruptions with two independent and hot-swappable controllers operating in an active-passive configuration.
Made for demanding environments
The SA3400D is engineered to provide outstanding performance in both NAS and SAN storage roles. Its throughput and random I/O performance support efficient SMB and NFS file serving as well as a range of iSCSI and Fibre Channel block storage applications.
Efficient and secure folder sharing
View, edit, and share data through desktop, mobile, and web-based applications. Enable user access to shared folders over SMB or NFS and leverage Microsoft AD or LDAP integration for efficient user access and permissions management.
Efficient cross-site file syncing
Sync or distribute data between servers with Synology Drive ShareSync to provide teams around the world with the latest work files. Or create a global file system spanning C2 Storage cloud storage and multiple Synology systems with Hybrid Share.

Built-in data protection
Back up PCs, servers, SaaS accounts, and VMs
Consolidate and automate backup tasks for PCs, servers, VMs, SaaS applications, and more with Active Backup Suite. Manage all backup tasks from a central console and quickly restore specific files, entire devices, virtual services, and employee SaaS accounts to keep your business running.
Create off-site backups for shared folders, LUNs, and more
Back up shared folders, LUNs, applications, and configurations from your Synology server onto a secondary server, an external device, or C2 Storage3 via Hyper Backup. Schedule backup tasks, keep the versions you need with flexible retention policies, and reduce backup sizes with built-in data deduplication. Or minimize lost data with Snapshot Replication, creating point-in-time snapshots at intervals as short as 5 minutes.

Business productivity solutions
Boost team productivity with collaborative tools
Improve collaboration in the workplace with Synology productivity solutions. Create, edit, and share documents across teams in real time with Synology Office. Host an on-premises mail server with MailPlus,4 providing web-based email access while retaining full data ownership. And stay connected via secure one-on-one chats, public channels, encrypted private channels, and group conversations in Synology Chat.
Sandbox and instantly restore critical services
Instantly restore backed up physical servers and VMs, or test new applications in a contained environment with Synology Virtual Machine Manager5 — a hypervisor for Windows®, Linux®, and Virtual DSM with built-in snapshots and version rollback functionality. Or host Docker containers on Synology Container Manager and benefit from easy management, automatic update notifications, and Compose support.
Supports industry-leading virtualization platforms
The SA3400D provides efficient storage for virtualized environments, with full certification for VMware® vSphere™, Citrix® XenServer™, and OpenStack. Synology Storage Console provides direct management from VMware® or Windows platforms, while VMware VAAI and Microsoft ODX support help offload and speed up data transfer operations.

Flexible options to meet changing needs
Flexibly scale storage capacity, optimize I/O performance, and meet different network needs with a range of expansion options.
Add storage capacity on demand
Scale server capacity up to 576 TB when your data storage needs increase by adding two 12-bay RXD1219sas expansion units.
Boost network and I/O performance
Add 10/25GbE connectivity with optional add-in cards. Create all-flash storage volumes with SAS SSD for lightening-fast I/O, or boost IOPS and cut down latency on HDD volumes by creating SAS SSD read/write cache volumes.
Up to
576 TB
raw capacity
The SA3400D can be configured with 25GbE networking. Up to
25GbE
networking
The SA3400D features up to 218,000 read and 92,000 write speeds when equipped with SSD cache. Up to
218/92K IOPS
read/write with SSD cache
- 1 Power Button and Indicator
- 2 High Availability Status Indicator
- 3 Alert Indicator
- 4 Mute Button
- 5 Drive Status Indicators
- 6 Drive Trays
- 7 Rail Kit Release Tabs
- 8 Power Ports
- 9 PSU Indicators
- 10 PSU Fans
- 11 PCI Express Expansion Slots
- 12 Console Ports
- 13 1GbE RJ-45 Ports
- 14 10GbE RJ-45 Ports
- 15 Expansion Ports
- 16 Reset Buttons
- 17 Remove Indicators
- 18 Alert Indicators
- 19 Status Indicators
- 20 Power Indicators


Hardware Specifications |
Controller | Number of Controller Module | 2 |
CPU | CPU Model | Intel Xeon D-1541 |
| CPU Quantity | 1 (per controller) |
| CPU Core | 8 |
| CPU Architecture | 64-bit |
| CPU Frequency | 2.1 (base) / 2.7 (turbo) GHz |
| Hardware Encryption Engine | |
Memory | System Memory | 8 GB DDR4 ECC UDIMM (per controller) |
| Memory Module Pre-installed | 8 GB (8 GB x 1) (per controller) |
| Total Memory Slots | 4 (per controller) |
| Maximum Memory Capacity | 64 GB (16 GB x 4) (per controller) |
| 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.
|
Storage | Drive Bays | 12 |
| Maximum Drive Bays with Expansion Unit | 36 (RXD1219sas x 2) |
| Drive Type (See all supported drives) | - 3.5” dual-port SAS HDD
- 2.5” dual-port SAS 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. |
External Ports | RJ-45 1GbE LAN Port | 2 (per controller) |
| RJ-45 10GbE LAN Port | 1 (per controller) |
| Expansion Port | 1 (per controller) |
| Expansion Port Type | Mini-SAS HD |
| Notes | This device's 1GbE LAN ports have a maximum transmission unit (MTU) size of 1,500 bytes. |
PCIe | PCIe Expansion | 1 x Gen3 x8 slot (x8 link) (per controller) |
Appearance | Form Factor (RU) | 2U |
| Size (Height x Width x Depth) | 88 mm x 482 mm x 724 mm |
| Weight | 19.7 kg |
| Rack Installation Support* | 4-post 19" rack (Synology Rail Kit - RKS-02) |
| Notes | The rail kit is sold separately |
Others | System Fan | 60 mm x 60 mm x 2 pcs |
| Fan Speed Mode | - Full-Speed Mode
- Cool Mode
- Quiet Mode
|
| Easy Replacement System Fan | |
| Power Recovery | |
| Noise Level* | 51.3 dB(A) |
| Power Supply Unit / Adapter | 500 watts |
| Redundant Power Supply | |
| AC Input Power Voltage | 100V to 240V AC |
| Power Frequency | 50/60 Hz, Single Phase |
| Power Consumption* | 257.78 watts (Access) |
| British Thermal Unit | 879.58 BTU/hr (Access) |
| Notes | - Power consumption is measured when it is fully loaded with Synology 12TB HAS5300-12T hard drive(s).
- Noise Level Testing Environment: Fully loaded with Synology HAS5300-8T 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 | - FCC
- CE
- BSMI
- VCCI
- RCM
- UKCA
- EAC
- CCC
- KC
|
Warranty | 5 Years |
| Notes | The warranty period starts from the purchase date as stated on your purchase receipt. (Learn more) |
Environment | RoHS Compliant |
Packaging Content | - Main Unit X 1
- Accessory Pack X 1
- AC Power Cord X 2
- Quick Installation Guide X 1
|
Optional Accessories | |
| 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. |