Okay, I cannot take it any more.

[Joe Pruett]

i have been doing it the ns way for years, mainly because it works with
*all* resolvers.  it used to be the case that some resolvers didn't like a
ptr query to return a cname and would choke.  using the ns method is
completely legal and everything understands it because as barry said, it
is ordinary delegation.  and personally i find cnames to be a major
problem and so i almost never use them.

On Fri, 26 May 2000, Barry Margolin wrote:
> 
> As far as the parent domain is concerned, there's not much difference
> between doing:
> 
> 216/29 NS  dns0.ancdf.org.
> $GENERATE 216-223 $ CNAME $.216/29
> 
> versus:
> 
> $GENERATE 216-223 $ NS dns0.ancdf.org.
> 
> However, for the administrator of dns0.ancdf.org, the latter is a bit more
> of a pain.  Instead of 8 lines in one zone file, he needs to create 8 zone
> files.  But since they're all almost identical, he can create one, make 7
> copies of it, and then edit them each to have the appropriate PTR record.
> 
> A reason that an ISP may favor the NS mechanism over the CNAME mechanism
> may have to do with the automated tools they use to maintain their DNS.
> Perhaps they haven't enhanced them to support RFC 2317, but they already
> support ordinary delegation.