[Pdns-users] Problems with Reverse Resolutions

Lorens Kockum lorens-pdns-3987 at tagged.lorens.org
Mon Dec 13 22:05:57 UTC 2004

On Mon, Dec 13, 2004 at 11:57:48AM -0600, Daniel Romero wrote:
> But if a set my "server" parameter to my PDNS IP, then this reverse query work fine!.. In other words..
> my reverse lookups work only if i use my own DNS server (PDNS server conected to internet) but.. 
> If i use any other valid DNS server, I can't  make a reverse resolv, like my PDNS server can't resolv reverse querys to external lookups.


In the same way that you have to obtain the domain name
ansel.com.mx in forward DNS (by buying it from a registrar, if
.com.mx is anything like .com), and then assign name servers
to it, you have to obtain the rights to the domain name
xxx.xxx.xxx.in-addr.arpa (by getting your ISP to assign and
route the IPs to you), and also assign name servers to it.

What is happening is that when you ask your PDNS server, it
is responding as an authoritative name server (because you
configured it to know that this IP address has that PTR), and
when you ask another DNS server, it is acting as a resolver, and
asking root-servers.net for a way to the answer. Somewhere, that
way to your pdns server is incomplete.

Your best bet is to ask the persons who assigned you the IP
block. If you have a /24 or bigger I don't think there should be
any problems.

If, of course, the IP addresses are "internal" RFC 1918 space,
then you just configure all the resolvers in use in the area so
that (example of

	name_of_my_pdns_server   IN A   ip_of_my_pdns_server
	34.168.192.in-addr.arpa  IN NS  name_of_my_pdns_server

Hope this helps.

#include <std_disclaim.h>                          Lorens Kockum

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