Domain renawals

Mark Andrews marka at isc.org
Thu Sep 22 19:28:33 UTC 2016


In message <CAAAwwbXLb=ZDJMRHvZ3_657fbh2ivXOQpZC2G8prK5JuccX_rw at mail.gmail.com>
, Jimmy Hess writes:
> On Thu, Sep 22, 2016 at 9:37 AM, Doug Barton <dougb at dougbarton.us> wrote:
> > On 09/21/2016 01:44 PM, Richard Holbo wrote:
> >> FWIW, as I'm in the middle of this right now. It would appear that many of
> > What do you think glue records are, and why do you think you need them? :)
> > (Those are serious questions, btw)
> 
> Glue records are also called "Host  records",  or Alternatively
> called: "Nameserver" records.
> These are A and AAAA records for your domain name which appear in the
> parent TLD zone,
> instead of the child zone.

No. They are COPIES of records held in the parent zone to bootstrap
access to the zone.  They NEED to appear in BOTH places.  If you only
have them in the parent zone then you have a broken delegation which
will fail intermittently for some resolvers when they learn that there
are no records in the child zone.

Named has code to detect this delegation error when it goes to load
a zone.  It blocks the load of the zone until you FIX the problem.
It does this so that the error is made visible to the operator of
the zone.

> Host records also typically appear in WHOIS, for example:   "$ whois
> ns5.yahoo.com"
> 
> If you think your registrar does not support them,  then you're
> probably having trouble with
> your registrar's user interface,  and just don't have the right
> procedure,   because the use
> of host records is  quite essential and necessary for at least one
> domain to self-host DNS......
> 
> 
> These records are non-authoritative and belong to the reply delegating
> nameservers for
> your domain to your servers,  and you need to duplicate a copy of all
> your NS, A, AAAA records in your
> child zone,  which must be identical to the parent's version of the records.
> 
> For example, suppose your domain name is "Example.com"
> And you want your nameservers to be  NS1.example.com,
> NS2.example.com,  NS3.example.com.
> 
> Because the nameservers exist in the same domain name which references them,
> the required DNS lookup graph is circular,  and your DNS zone becomes an isla
> nd!
> 
> In order for clients to find your nameserver  to figure out what
> NS1.example.com resolves to,
> it first needs to be able to find a nameserver for  Example.com,
> which is NS1.example.com.
> 
> This is what is circular without a Hint in the Additional section of
> the DNS reply from the parent nameserver.
> 
> The glue record in the parent zone is used to tell the parent TLD
> server to include the IP address of
> your nameserver in the Additional Section  of the DNS reply,  so you
> can  bootstrap DNS resolution
> for Example.com.
> 
> 
> 
> > Doug
> --
> -JH
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org



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