Replacing DNS with GTM

The biggest difference between the GTM and LTM, as mentioned earlier, is traffic doesn’t actually flow through the GTM to your servers. The GTM is an intelligent name resolver, intelligently resolving names to IP addresses. Once the GTM provides you with an IP to route to you’re done with the GTM until you ask it to resolve another name for you. Similar to a usual DNS server, the GTM does not provide any port information in its resolution. The LTM doesn’t do any name resolution and assumes a DNS decision has already been made. When traffic is directed to the LTM traffic flows directly through its’ full proxy architecture to the servers it’s load balancing. Since the LTM is a full proxy it’s easy for it to listen on one port but direct traffic to multiple hosts listening on any port specified.