simple local caching DNS

[Barry Margolin]

In article <cmb7cq$13o1$1 at sf1.isc.org>,
 Gregory Hicks <ghicks at cadence.com> wrote:

> > From: "Clarence Brown" <clabrown at granitepost.com>
> > To: "Charles Cala" <charles_cala at yahoo.com>, <bind-users at isc.org>
> > Subject: Re: simple local caching DNS
> > Date: Wed, 3 Nov 2004 13:02:56 -0500
> > 
> > Well, I guess I'm a little unsure of having a reverse zone without 
> > a forward zone.... What are the ramifications of that? 
> 
> Well, here is MY reverse...
> 
> metis% cat db.127.0.0
> @ IN  SOA metis.Cadence.COM. root.metis.Cadence.COM. ( 2002120212 1H 15M 1W 
> 1H )
>   IN  NS  metis.cadence.com.
> 
> 1.0.0.127.IN-ADDR.ARPA.       	IN  PTR   localhost.

That's not relevant to the OP's problem, since nslookup is trying to 
resolve the nameserver's address, which is 10.15.10.2, not 127.0.0.1.  
He'll need to add 10.in-addr.arpa to his nameserver's configuration.

I believe that nslookup only does a reverse lookup, it doesn't try to 
verify the name with a forward lookup.  So it should be safe to make 
your internal server authoritative for 10.in-addr.arpa.  This is, in 
fact, generally a good idea, because other applications that try to do 
reverse lookups of private IPs will not cause your server to recurse, 
which should speed these applications up.

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***