“The time has come,” the Walrus said, “To talk of many things: Of shoes—and ships—and sealing-wax—Of cabbages—and kings—And why the sea is boiling hot—And whether pigs have wings.”
It’s time we tied up loose ends. We’ve already covered the mainstream of DNS and BIND, but there’s a handful of interesting niches we haven’t explored. Some of these may actually be useful to you, such as instructions on how to accommodate Active Directory with BIND; others may just be interesting. We can’t in good conscience send you out into the world without completing your education!
We talked about CNAME resource records in Chapter 4. We didn’t tell you everything about CNAME records, though; we saved that for this chapter. When you set up your first nameservers, you probably wouldn’t have cared about the subtle nuances of the magical CNAME record. Some of this trivia is interesting, some is arcane. We’ll let you decide which is which.
If you’ve ever renamed your zone because of a company reorganization or acquisition, you may have considered creating a single CNAME record that pointed from the zone’s old domain name to its new domain name. For instance, if the fx.movie.edu zone were renamed magic.movie.edu, we’d be tempted to create a single CNAME record to map all the old domain names to the new names:
fx.movie.edu. IN CNAME magic.movie.edu.
With this in place, you’d expect a lookup of empire.fx.movie.edu to result in a lookup ...