Now that you have an understanding of how DNS queries are formed and answered, as well as the meaning of the various flags and component parts of a DNS message, you will better understand various diagnostic outputs from utilities we're going to look at in Chapter 10, Debugging without Tears- DNS Diagnostic Tools.
Furthermore, you now have an understanding of the distinction between UDP and TCP as it relates to DNS and why your nameservers are required to respond to both.
Finally, we've dispelled any misconceptions around how nameserver selection works, and we also know how DNS queries progress from the root servers through to the authoritative servers.
