OT: checking subnet delegation?

[Phil Mayers]

On 04/01/11 15:32, online-reg wrote:
> Hi All: I have a /28 that was supposed to be delegated to my NS by my ISP.
>
> How can I check that it is correctly delegated? I have the in-addr.arpa
> zone
> configured in my NS and it resolves properly when I test it locally, but if
> I test using a remote service no reverse is found.

dig +trace -x 216.218.227.128

>
> The subnet is 216.218.227.128/28
>
> it should be delegated to ns.enigmedia.com and ns1.enigmedia.com

You'll see that the trace ends in a CNAME to the sub-/24 zone, along 
with NS records:

128.227.218.216.in-addr.arpa. 86400 IN	CNAME 
128.128-143.227.218.216.in-addr.arpa.
128-143.227.218.216.in-addr.arpa. 86400	IN NS	ns.enigmedia.com.
128-143.227.218.216.in-addr.arpa. 86400	IN NS	ns1.enigmedia.com.

...which looks correct to me?

Your zone then needs to contain:

128.128-143.227.218.216.in-addr.arpa.  IN PTR host128.nnn
129.128-143.227.218.216.in-addr.arpa.  IN PTR host129.nnn