Subject: Re: DNS lookup for internal adresses
To: None <>
From: None <>
List: netbsd-users
Date: 03/14/2002 23:55:32
On Wed, Mar 13, 2002 at 09:37:04PM -0800, Michael K. Sanders wrote:
> writes:
> >Is it possible to use bind to do reverse lookups for small nets like
> > and similar? Where my ISP does normal reverse for
> >the normal IP block, and I just want my DNS to do reverse for my small
> >chunk of the block?
> You want to do this for a non-RFC1918 block, right?  It's quite possible
> and done frequently, your provider just has to be willing to set it up.
> See RFC 2317 on Classless IN-ADDR.ARPA delegation:

Ah. I left out a few details. Not to worry, the suggestion of a zone per
IP solved my problems nicely. 

I have two name servers, one externally visible and one internally visible.
The external server uses something like what is described in rfc 2317. The
only vaguely tricky part was making sure my tables line up with my ISP's
tables. No biggie, a phone call to "the guy" and I was good to go.

My internal server is the real problem. The problem is that doing a
reverse lookup requires sending a query to my ISP's servers, and then
getting a response back that sends clients to my servers. Usually not
an issue, but when the power flickers I have a chicken-and-egg problem
with various programs failing to start because my border machine hasn't
finished booting. 

To solve my problems I now have the external server doing the rfc 2317
thing as before, and the internal server has one-IP-per-zone reverse tables.
So, next time the power company reboots me I should have a much more robust
boot process. Hopefully. 

Thanks all for the suggestions.
"A method for inducing cats to exercise consists of directing a beam of
invisible light produced by a hand-held laser apparatus onto the floor ...
in the vicinity of the cat, then moving the laser ... in an irregular way
fascinating to cats,..." -- US patent 5443036, "Method of exercising a cat"