I've rented a dedicated server for several years with a number of domains. I've got a coding background so am comfortable with that side of the tech, but I hate that I still don't truly understand DNS settings.

Example: My provider (hostgator) just told me that my parent nameservers are not correctly configured as there is no A record for my primary nameserver.

What book/link/tutorial should I read to go from kind of understanding that comment to really understanding it & knowing exactly what I need to do to fix it rather than trial & error which is what I usually do.

Thanks

BTW I'm using a WHM/cpanel linux setup at hostgator but am eager to learn the fundamentals.