Setting up reverse DNS correctly

Michael Varre bind9 at kishmish.com
Thu Jul 15 20:14:42 UTC 2004



> -----Original Message-----
> From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org] On
> Behalf Of Craig L. Ching
> Sent: Thursday, July 15, 2004 10:56 AM
> To: comp-protocols-dns-bind at isc.org
> Subject: Re: Setting up reverse DNS correctly
> 
> "Justin Randall" <j_randall_ at hotmail.com> wrote in message
> news:<cd4tu0$26e2$1 at sf1.isc.org>...
> > There are two solutions in this case, the one that is least likely to be
> the
> > actual solution would be to ask your ISP to delegate a portion of the
> > reverse records (PTR RRs) over to your name servers.  There is a CNAME
> hack
> > that can easily accomplish this.
> >
> > The most common and more likely solution is to contact you ISP and
> request a
> > reverse entry be made in their records to the effect that a query
> against
> > your IP will resolve your mail server FQDN.
> >
> When you say my ISP, you mean the people who assigned the IP address
> to me, is that correct?  And even though I run my own name servers,
> they have to do something on their end to make it work?

Yes.

> 
> I'm afraid to say I've never taken the time to really understand DNS
> details, it mostly just works for me.

You should take the time to read how it all comes together before you jump
right into it.

  Could someone elaborate on how
> the ISP fits into this scene?  Does it have something to do with the
> root servers knowing which ISPs own what blocks of IP addresses?  I
> always thought that once I gave my name servers to a registrar, the
> root servers contacted my server directly about my domain names.
> Sorry for such a novice question, feel free to direct me elsewhere if
> you think it's necessary.  And thanks for the help!

Netsol type registrars take care of forward lookups.  Reverse lookups are
handled via ARIN (In the US). Its more or less the same process as with
forward hostname lookups, only reverse lookup root servers are arin, and
they have be be delegated on down just like forward lookup dns.  Your isp
basically needs to delegate reverse lookup capabilities to your name
servers.  Ask them to do that, then get more familiar with the whole
process, then try try again.

http://www.stamey.nu/DNS/HowReverseLookupWorks.asp


mv

> 
> Cheers,
> Craig




More information about the bind-users mailing list