DNS Failover

What is DNS Failover?

Failover is a service that can be applied to a DNS record that changes where the record points to in the event that the primary endpoint is unavailable.

Failover with built-in system monitoring is the most popular service we offer and has saved businesses millions every year in lost revenue due to downtime.

How It Works

One Endpoint, No Failover

For this example, we are going to use an A (apex) record for our domain example.com. We want this record to send users that query our domain to our website, so we will point it to the IP address of our web server. That means, whenever a user queries this A record they will be sent to our website.

Endpoint Unavailable

Right now, we don’t have failover enabled so if the IP address in our A record (web server) is unresponsive, users won’t be able to reach our website.

One Endpoint with Failover

Let’s enable failover. We can now choose a secondary IP address (backup web server) that will be used if our primary endpoint (web server) is unavailable. As soon as you apply failover to a record, our monitoring service will check to see if your IP is available every 2-4 minutes.

If our monitoring nodes are unable to get a response from the primary IP from two different locations, it will not longer be used for that record. We will then issue a check for your secondary IP to make sure it is responding before automatically moving traffic to it. The account administrator will receive an email alert when the failover occurs.

Available Endpoint Served

If one of the providers were to be unavailable, resolving nameservers would only send query traffic to the available nameserver set. All of this happens automatically with no appreciable effects to end users.

One Endpoint, No Failover

blurple server

Endpoint Unavailable

grey server


One Endpoint with Failover


Available Endpoint Served

multiple down

Specify up to four backup IP addresses.

Monitoring available over: TCP, UDP, HTTP, or HTTPS protocols on any port you desire.

Updates (failover and failback) are propagated instantly across our entire network.

Need more advanced Failover?

Our new product, Constellix, offers more granular monitoring, so your failover changes happen quicker.

But wait theres more...

  • Failover is available for: A, AAAA, ANAME, and CNAME records
  • Choose up to 14 different monitoring locations
  • 30 second to one day monitoring intervals
  • Traceroute and visual traceroute in notification report
  • Avoid false positives with verified checks
  • All IP's in the failover config are constantly monitored (not just when the primary is down)

Learn more


Small Business



3 Failover Records Included

Buy Business


10 Failover Records Included

Buy Corporate

Additional Records

$4.95 per record / year

10-Pack of Records

$45.95 per 10-pack / year

Related Articles


Tutorials: Learn how to setup DNS Failover and system monitoring with these tutorials.

Learn how

New Study: Q1 2016, our DNS Failover services saved clients an estimed $525 million in revenue.

Read more
On off graphic

What is DNS Failover and how does it work? Five minute lesson with infographics

Read more

TTL's (Time to Live) the long and short of it. When to keep them long, and when to shorten them.

Read more

Like what you see?

Start your free (no credit card required) 30 day trial and you can have fast DNS in a matter of minutes.
Yep, it really is that easy.

Sign up