Name servers search public records to resolve IP for a specific FQDN. Many times, we will want to define our own private FQDN and resolve it to an IP, without relying on DNS resolution. 

NOTE: static FQDN-IP setting will supersede DNS resolution results. This also gives us the flexibility to alter the resolved IPs from name server for the same FQDN.

There's a "tracking" option to track a specific upstream host IP or the mapped IP. If the tracking fails, the FQDN will map to the backup IP. This is useful for some SD-WAN failover scenarios.

Go to "Device MAC --> System" menu