BIG-IP Global Traffic Manager (GTM) can function as a load balancer in front of a pool of DNS servers. In this situation, BIG-IP GTM checks incoming DNS queries and if the query is for a wide IP, load balances it to the appropriate resource. Otherwise, BIG-IP GTM forwards the DNS query to one of the servers in a pool of DNS servers, and that server handles the query.
Listeners control how BIG-IP GTM handles network traffic. A listener is a specialized virtual server that is assigned a specific IP address. A wildcard listener is a special listener that is assigned an IP address of 0.0.0.0 and DNS query port (port 53). When traffic is sent to the IP address of a listener, BIG-IP GTM either handles the traffic locally or sends the traffic to the appropriate resource.
Perform these tasks to load balance non-wide IP traffic to a pool of DNS servers.