DNS recommendations - the paper

    CNAMEs map nicknames to cannonical names.
Fortunately they're not *that* agressive. :-)

    CNAMEs have very few uses (see above example, RFC 2317, ...).
    Be especially aware that nicknames must not be used as the
    right hand of NS, MX, ... RRs.
Having CNAMEs in the RHS of an NS RR is not
explicitly forbidden (yet?), so there's only
an indirect way to explain why they are: they
collide with glue RRs, leading to a violation
of the rule that CNAMEs may not have any other
RRs associated with them:

  XX. SOA ()
  ns.foo.xx.  A 1.2.3.4
  foo.xx.     NS ns.foo.xx.

  foo.xx. SOA ()
  @           NS ns.foo.xx.
  ns.foo.xx.  CNAME myhost.foo.xx.

This leads to the illegal combination:
ns.foo.xx.  CNAME myhost.foo.xx.
ns.foo.xx.  A     myhost.foo.xx.

but not [visibly] in either of the zone files
themselves!


	Piet