Multiple nameservers on one server

[Paul Howarth]

Eight32 wrote:
> On Tue, 2006-03-28 at 16:12 +0100, Paul Howarth wrote: 
>> Stuart Murray-Smith wrote:
>>> I want to set up a DNS server that will 'emulate' multiple nameservers
>>> on one server ie when queried, the answer will appear as if _this_
>>> physical server is the SOA for _this_ domain only.
>> What is it about a server handling multiple domains that gives it away 
>> as handling multiple domains rather than just the one that's being 
>> queried? I can't think of anything offhand.
>>
>>> How would I list multiple reverse lookup (zzz.yyy.xxx.rev) files in named.conf?
>> Same way that you would handle any other multiple zones; there's nothing 
>> special about reverse zones.
>>
>> Paul.
> 
> Hi Paul.
> 
> Thank you for replying :-)
> 
> I've Googled and only ever seen examples of named.conf's with one
> reverse zone (yet multiple forward zones [1, 2, ..., n] for which the
> reverse zone is SOA). I'm trying to provide primary nameserver services
> to multiple domains such that:
> 
> /etc/named.conf looks like:
> 
> -----8<----------8<----------8<----------8<----------8<-----
> 
> zone "yyy.xxx.www.in-addr.arpa" {
> 	type master;
> 	file "/var/named/yyy.xxx.www.rev";
> 	allow-query { any; };
> 	};
> 
> -----8<----------8<----------8<----------8<----------8<-----
> 
> and /var/named/yyy.xxx.www.rev looks like:
> 
> -----8<----------8<----------8<----------8<----------8<-----
> 
> $TTL 3600
> $ORIGIN yyy.xxx.www.IN-ADDR.ARPA.
> ;
> @ IN SOA ns1.domainname_0.tld. admin.domainname_0.tld. (
> 		0603240000 ; serial
> 		10800      ; refresh
> 		3600       ; retry
> 		604800     ; expire
> 		10800      ; minimum
> 		)
> ;
> 		IN NS ns1.domainname_0.tld.
> ;
> 		IN NS ns1.domainname_1.tld.
> ...
> 		IN NS ns1.domainname_n.tld.
> ;
> 		vvv.www.xxx.yyy IN PTR ns1.domainname_0.tld.
> ;
> 		vvv.www.xxx.yyy IN PTR ns1.domainname_1.tld.
> ...
> 		vvv.www.xxx.yyy IN PTR ns1.domainname_n.tld.
> 
> ;
> 
> -----8<----------8<----------8<----------8<----------8<-----
> 
> I'm going to guess that I can either adopt the following naming scheme
> by changing the generic:
> 
> file "/var/named/yyy.xxx.www.rev";
> 
> to:
> 
> file "/var/named/yyy.xxx.www.domainname_0.rev";
> 
> in /var/named.conf say,
> 
> -----8<----------8<----------8<----------8<----------8<-----
> 
> zone "yyy.xxx.www.in-addr.arpa" {
> 	type master;
> 	file "/var/named/yyy.xxx.www.domainname_0.rev";
> 	allow-query { any; };
> 	};
> 
> zone "yyy.xxx.www.in-addr.arpa" {
> 	type master;
> 	file "/var/named/yyy.xxx.www.domainname_1.rev";
> 	allow-query { any; };
> 	};
> 
> ...
> 
> zone "yyy.xxx.www.in-addr.arpa" {
> 	type master;
> 	file "/var/named/yyy.xxx.www.domainname_n.rev";
> 	allow-query { any; };
> 	};
> 
> -----8<----------8<----------8<----------8<----------8<-----
>  or change statements in reverse zones by having one 'type master;' and
> the others 'type slave;'?

No, you can't do this. A given IP address should live in only one zone. 
Whilst it's possible to have multiple PTR records for an IP address, 
it's rather pointless.

Let's think about this a different way.

Supposing you have domainname_0.com and domainname_1.com, with:

www.domainname_0.com = 10.1.2.3
www.domainname_1.com = 10.1.2.4

And presumably the reverse lookups for those IPs should result in the 
same hostnames. What else do you need apart from this (which is a bog 
standard configuration)? Answer in terms of DNS queries and results 
rather than how you think it should be configured.

Paul.