Name for reverse zone

[Barry Margolin]

In article <c93a9r$1j6i$1 at sf1.isc.org>,
 keilj_33 at yahoo.com (Jeffrey Keil) wrote:

> Hello:
> 
> This is probably a stupid question, but if the network address is
> 64.207.45.64/26 (the subnet mask is 255.255.255.192), would the zone
> in the /etc/named.conf file be:
> 
> zone "64.45.207.64.in-addr.arpa" {
>         type master;
>         file "64.207.45.64.rev";
> }
> 
> Would you need all four octets in the zone name because the subnet
> mask isn't 255.255.255.0?

When using RFC 2317 to implement reverse DNS for a block smaller than 
/24, the name of the reverse zone can be almost anything.  A common 
naming convention is to use the CIDR block name, e.g. 
64/26.45.207.64.in-addr.arpa.  Another thing that some sites do is put 
the PTR records in their forward domain.

All that really matters is that the name matches how the reverse domain 
is delegated in the parent domain.  If you put the PTR records in the 
forward domain, the parent domain would contain:

64 IN CNAME 64.yourdomain.com.
65 IN CNAME 65.yourdomain.com.
....
127 in CNAME 127.yourdomain.com.

-- 
Barry Margolin, barmar at alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***