Synology High Availability

Maximize uptime, minimize cost

damages are caused by the average service disruption
of small businesses never reopen after catastrophic data loss
of small and medium-sized businesses remain unprepared for disaster

Unexpected service disruptions can cost your company big money as well as cause logistical headaches for your IT department. Synology High Availability (SHA) alleviates these issues and delivers a hassle-free method to mirror data and maximize your service uptime. SHA is available for free on select Synology NAS.

How does it work?

SHA combines two Synology NAS servers into one high-availability cluster (or HA cluster). One server assumes the role of active server, while the other becomes a standby passive server. The active server handles all data requests and services, while everything is continuously replicated to the passive server. This provides a complete hardware and data redundancy solution in case of unforeseen accidents. Watch the video to learn more about SHA. See more videos

Real-time protection, service uptime maximization

Critical data require a well-rounded backup and recovery strategy. With its data mirroring mechanisms, SHA makes sure your data is safely stored on another physical unit. This process is achieved in real-time, so in the event of hardware failure, all data can be accessible soon after.

Don't sweat it with automatic failover

The two servers communicate via a Heartbeat connection. If the active server malfunctions or its power supply fails, the passive server automatically kicks in and takes over all services without human intervention. That means your employees or customers can continue accessing files or services, without knowing anything went wrong.

No-hassle installation and maintenance

The intuitive user interface makes SHA super simple to set up and get running. With its handy, built-in management tools, you can easily monitor the HA cluster and perform maintenance, without needing to acquire additional technical knowledge. Learn how to setup a SHA configuration

Highly available application server

Intuitive application serving is an essential part of the Synology experience. Whether it's web, mail, syslog, FTP, or Cloud Station, DDSM, all Synology packages and built-in services are compatible with SHA to prevent downtime when hardware failure occurs. Learn more about other features

Virtualization ready

DiskStation is an ideal target for accessing virtual machines through iSCSI. SHA ensures stored virtual machines are constantly available. Certified for VMware, Citrix, and Windows Server, a Synology NAS also benefits from a user-friendly LUN manager for rapid creation, cloning, or removal. Learn more about virtualization support

Quorum Server Ready

The timing for the passive server to take over the main operation is critical. Quorum Server plays the key role in reducing the occurrence of split-brain effectively, thus maximizing service continuity and data consistency.

Best-in-class availability

SHA runs on a wide range of Synology NAS servers, so your business can find the best option for your environment and budget. Already chosen by banks, hospitals, universities and governments, SHA does not compromise between cost and reliability.

Want to know more?

SHA includes many advanced tools and features. See the links below to learn more and get started.

SHA White Paper

Get the technical details regarding SHA and see our suggested best practices.

Learn More

Get started with SHA

Do you already have two servers with SHA? See this step-by-step tutorial.

Learn More

Applied Models

  • FS3017
  • FS2017
  • RS18017xs+
  • RS4017xs+
  • RS3617xs+
  • RS3617xs
  • RS3617RPxs
  • DS3617xs
  • DS1817+
  • DS1817
  • DS1517+
  • DS1517
  • RS18016xs+
  • RS2416+
  • RS2416RP+
  • DS916+
  • DS716+II
  • DS716+
  • RS815+
  • RS815RP+
  • DS3615xs
  • DS2415+
  • DS2015xs
  • DS1815+
  • DS1515+
  • DS1515
  • DS715
  • DS415+
  • RS3614xs+
  • RS3614xs
  • RS3614RPxs
  • RS2414+
  • RS2414RP+
  • RS814+
  • RS814RP+
  • RS10613xs+
  • RS3413xs+
  • DS2413+
  • DS1813+
  • DS1513+
  • DS713+
  • RS3412xs
  • RS3412RPxs
  • RS2212+
  • RS2212RP+
  • RS812+
  • RS812RP+
  • DS3612xs
  • DS1812+
  • DS1512+
  • DS412+