larger subnet and zone files

[Roy Arends]

On Mon, 11 Jun 2001, Adam Lang wrote:

> If I want to have my DNS administer a 10.10.0.0 (255.255.0.0) network, do I
> need separate zones for each 255.255.255.0 network?  The main reason I'm
> asking is in regards to how the reverse zone would look.

Lets say you would have a 192.168.0.0 network (lets use this private space
address for illustration purposes). You could put everything under the /16
node in one zonefile.

Note that, when using reverse addressing, these are no IP addresses but
just FQDNs (fully qualified domain names).

A 192.168.0.0/16 network is then simply a zone which is called
168.192.in-addr.arpa. Everything within the network can now be simply put
in
one zone.

If you have an adress that is 192.168.128.233, then you would have a RR
like
this:

233.128.168.192.in-addr.arpa. PTR somename.example.com.

If you want to give some departement in your company a specific part of
the network, say a 192.168.222/24 segment, and let them handle their own
reverse-mapping, simply delegate that part of the zone to their
nameserver:

222.168.192.in-addr.arpa. NS their.nameserver.example.com.
222.168.192.in-addr.arpa. NS also-their.nameserver.example.com.

Note: the adresses used are private-space, and are not delegated by the
in-addr.arpa zone.

Regards,

Roy Arends
Nominum