Somewhat OT: Getting control of reverse for my /29

Robert Moskowitz rgm at
Mon Nov 1 23:15:59 UTC 2004

At 05:39 PM 11/1/2004, KSP wrote:
>You should be able to get Qwest to do this.  As Marco points out, though,
>it may not be as easy to convince them as it is to configure.  RFC 2317
>outlines the technical parts:
>"This document describes a way to do IN-ADDR.ARPA delegation on non-octet
>boundaries for address spaces covering fewer than 256 addresses."
>This should not be an uncommon request for an ISP of Qwest's size.

I just went through this with my /26 at DSL.NET.

You have to learn your ISP's procedure for non-octet aligned reverse 

some use  (n being the first and m being the last 


some use  (n being the first and c being the block size)


With this delegation, your work is easy, just supply the PTR records for 
ALL the addresses (even those that are your network and broadcast 
addresses). For those addresses without any host, use

The ISP has the real work, but thanks to $GENERATE, it is not all that hard 
(the RFC was written before the $GENERATE).

Finally, get yourself someone to secondary your new zone.  Your ISP may 
wash their hands, saying, 'its all yours'.  get someone on a different ISP, 
preferably geographically different area to be your seconday.  And consider 
returing the favor.

More information about the bind-users mailing list