Default/Wildcard Query Response
Shane Kinsch
shane.kinsch at netracorp.com
Wed Mar 16 17:27:24 UTC 2005
Shane Kinsch wrote:
> phn at icke-reklam.ipsec.nu wrote in message
news:<bgd0di$1j4l$1 at sf1.isc.org>...
> > Shane Kinsch <shane.kinsch at netracorp.com> wrote:
> > > phn at icke-reklam.ipsec.nu wrote in message
news:<bgacc9$2bjv$1 at sf1.isc.org>...
> > >> Shane Kinsch <shane.kinsch at netracorp.com> wrote:
> > >> > phn at icke-reklam.ipsec.nu wrote in message
news:<bg6dqi$1j0$1 at sf1.isc.or=
> > g>...
> > >> >> Shane Kinsch <shane.kinsch at netracorp.com> wrote:
> > >> >> > Does anyone happen to know a quick and dirty way of taking
any traff=
> > ic
> > >> >> > being requested and give the person doing the query a
default IP?
> > =20
> > >> >> > For example... Let's say you were a hosting company or a
domain name
> > >> >> > registration firm and you are registering (or allowing
people to
> > >> >> > register) domain names using your DNS servers.
> > =20
> > >> >> > I would like to direct traffic of the new domain to an IP
address su=
> > ch
> > >> >> > that person X registers a domain xyz.com and uses our DNS
servers fo=
> > r
> > >> >> > resolution. I would like to have a default statement
somewhere that
> > >> >> > when queried, and the domain is not locally setup, it
responds to a
> > >> >> > default IP address thus sending the traffic to a default
"domain not
> > >> >> > setup" page.
> > =20
> > >> >> > Any help is appreciated. Please respond to the e-mail
address below
> > >> >> > and copy the newsgroup.
> > >> >>=20
> > >> >> You ask in news and will receive answer with news ...
> > >> >>=20
> > >> >>=20
> > >> >> Try a DNS wildcard '*' :
> > >> >>=20
> > >> >> * IN A <ip-of-wildcard>
> > >> >>=20
> > >> >> This may be combined with other RR and the general rule is=20
> > >> >> that "closest fit" will match.
> > >> >>=20
> >
> > >> > Where would this go? In the root's cache? I'm not looking
for domain
> > >> > specific as I don't know who is pointing to me. I want to
take any
> > >> > and all generic traffic and redirect to a generic start page.
> > >>
> > >> In the zone's zonefile. This is "just another resource-record"
among othe=
> > >> rs.
> >
> > > I don't think you understand what I'm asking. There is no ZONE
to put
> > > it in. It doesn't exist. I need a "wildcard" zone or some
config
> > > change that will respond to anything if asked with an IP that I
give.
> > > Again, let's say you point your domain to my servers... they
won't
> > > respond because I am not the SOA for your domain... now let's say
I
> > > make some magic change to my DNS servers to respond with an IP,
even
> > > though I'm not the SOA. Is this possible??
> >
> > If you want this to happen for evetry TLD then you must run
> > yout own root-servers. As rootserver you have a zoen for '.', put
your
> > wildcard there and youre done.
> >
> > There is a number of implications with running a root-server, and
for the
> > time beeing i think it's time to advice you to drop this idea.
> >
>
> I know other hosting organizations are doing this, so I'll have to
dig
> into this a little deeper. Thanks phn for your help. -- Shane
I just wanted to update anyone interested on how this actually works.
The Problem: I needed to configure named to reply to <any> request
with default zone data such that a query for <random-domain>.<gTLD>
will always result in a reply.
Why would anyone do this you ask? Hosting companies could do this for
ease of use in setting up a new hosted domain for their customers or an
ICANN Accredited Registrar may default DNS servers to newly registered
domain names pointing to their PPC (Pay Per Click) until the new owner
changes name servers, vs. managing which domains are actually using
their name servers and the administrative overhead this brings in
"managing" DNS services.
To do this, you will need to run a separate named.conf and in this
case, I'm calling it wild.conf. It will also bind to a different IP of
course if you're running this on your existing DNS servers. Here's a
sample:
wild.conf:
---------------- snip -------------- snip --------------
zone "22.33.44.in-addr.arpa" in {
type master;
file "master/db.wild-reverse-remote";
};
zone "1.168.192.in-addr.arpa" in {
type master;
file "master/db.wild-reverse-local";
};
zone "." in {
type master;
file "master/db.wild";
};
---------------- snip -------------- snip --------------
Note the above, that you will now need to reverse your in-addr.arpa.
I'm doing this for both local and remote addresses. The normal root
hint is now mastered and referring to db.wild. I'll only show the
Remote and db.wild here.
db.wild-reverse-remote:
---------------- snip -------------- snip --------------
$TTL 14400 ; 4 hours
;
; Last Modified by: Shane Kinsch
; 08.07.04 Created and standardized
;
$ORIGIN 22.33.44.in-addr.arpa.
@ IN SOA ns1.yourNORMALnameserver.net. you.yourdomain.com. (
2008070400 ; Serial revision
10800 ; Refresh after 3 hrs.
3600 ; Retry after 1 hr.
604800 ; Expire after 1 week
86400 ) ; Min. TTL of 1 day
@ IN NS ns1.yourWILDnameserver.net.
IN NS ns2.yourWILDnameserver.net.
;
11 IN PTR ns1.yourWILDnameserver.net.
12 IN PTR ns2.yourWILDnameserver.net.
---------------- snip -------------- snip --------------
db.wild:
---------------- snip -------------- snip --------------
;
; Last Modified by: Shane Kinsch
; 08.07.04 Created and standardized
;
; ZONE .
. 86400 IN SOA ns1.yourWILDnameserver.net.
you.yourdomain.com. (
2004080700 ; Serial revision
1800 ; Refresh after 30 mins
300 ; Retry after 5 mins
604800 ; Expire after 1 wk.
86400 ) ; Min. TTL of 1 day
. IN NS ns1.yourWILDnameserver.net.
. IN NS ns2.yourWILDnameserver.net.
* IN A 44.33.22.13
---------------- snip -------------- snip --------------
Once started, if you assign a domain with the WILD name servers above,
any query against ns1/ns2 will always result in 44.33.22.13!
Keep in mind, the only reason why someone would request a query against
this 'wildcard' dns configuration is if they were told to from the
root-servers for the domain they're requesting. Only domains assigned
to this will use it and every request for an answer to their query will
be replied to with the wildcard IP.
Shane Kinsch
NetraCorp LLC / Global Internet
More information about the bind-users
mailing list