How to configure DNS server to forward queries about particular domain AND all of its subdomains

Question

I have DNS server (linux box with bind9), which is authorative for some domains, and forward all other queries to external DNS server of my ISP provider.

So far no problem.

Now I want that queries about some specific domains were forwarded to my internal DNS server, f.e.:

zone "some_domain" {
       type    forward;
        forwarders {
                some_internal_dns_ip;
        };
};

So far still no problem, all works ok.

But then, I want also to forward some reverse DNS queries to my internal DNS. So, I have added:

zone "16.172.in-addr.arpa" {
        type    forward;
        forwarders {
                some_internal_dns_ip;
        };
};

And this doesn't work as I expect. Queries about "16.172.in-addr.arpa" (for example 1.16.172.in-addr.arpa) are resolved correctly, but reverse queries about full address (for example 1.1.16.172.in-addr.arpa) are not. I understand that my server should use here some recursive query, but could not configure it. I have already tried adding following options

recursion yes;
allow-recursion { 127.0.0.1; };
allow-recursion-on { 127.0.0.1; };

but with no success . (I have used loopback address here, because I need this functionality only for my DNS host, and not for its clients) Any suggestions?

I am confused. Do you have three servers; bind, ISP, and another internal server? If so does the internal server resolve the request for 172.16.1.1? — BillThor, Feb 25 '11 at 21:28
Yes - Exactly, and yes, internal DNS server correctly resolves reverse query for 172.16.1.1. All other queries are resolved by external ISP DNS server (by using global "forwarders" option). What I want to achieve, is my bind9 server to be also able to resolve reverse queries about addresses like 172.16.1.1 (only on this bind9 server, it doesn’t have to resolve it for clients using this bind server) — user71061, Feb 27 '11 at 21:23
Why would forwarding of the reverse zone not work? Is the ISP server queried? Try using tcpdump. — Marki, Aug 11 '13 at 18:26

score 8 · Answer 1 · edited Sep 02 '13 at 15:15

8

This is because bind creates the "empty zones" by default. So, your name server is the master for "16.172.in-addr.arpa." zone and return with "NXDomain" for your answers.

If you define "empty-zones-enable no;" in named.conf this will work as you expect.

edited Sep 02 '13 at 15:15

slm

7,615
16
56
76

answered Sep 02 '13 at 11:24

Allan GooD

81
1
2

This was the explanation for my experiencing the same problem. – anderbubble Mar 04 '15 at 17:40
And for me as well, on Ubuntu 14.04 – marcolz Nov 02 '15 at 09:19

score 2 · Answer 2 · edited Aug 29 '14 at 05:11

2

I had the same problem, you are just missing IN in your named.conf syntax:

zone "5.10.in-addr.arpa." IN {

    type forward;
    forwarders {10.5.0.1;};
};

zone "6.10.in-addr.arpa." IN {

    type forward;
    forwarders {10.6.0.1;};
};

It is confusing as master / slave zones don't need it. Anyhow that's what fixed it for me.

edited Aug 29 '14 at 05:11

masegaloeh

18,236
10
57
106

answered Aug 28 '14 at 22:14

user239921

21
1

score 1 · Answer 3 · answered Apr 04 '12 at 04:10

1

Two approaches...

Make BIND a master for 16.172.in-addr.arpa. Within the zone file, use NS records to delegate to the other internal server.

OR

Make BIND a slave for 16.172.in-addr.arpa. Set the other internal server as a master.

answered Apr 04 '12 at 04:10

Joe Sniderman

2,809
1
22
26

How to configure DNS server to forward queries about particular domain AND all of its subdomains

3 Answers3

Linked