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
Endpoint Unavailable
Or
One Endpoint with Failover
Available Endpoint Served
