Classless Reverse zones

[Bob Vance]

>I guess the other way around would be to make 116.10.in-addr.arpa
>dynamic and then define as many other static class C reverse zones
>separate to that.

What problem are you trying to solve, exactly?

Are you really wanting to delegate reverse zones to some other server or
are you just trying to separate dynamic updates from the static entries.


Anyway, CNAME way:

;;$ORIGIN 116.10.in-addr.arpa.
   ...
$GENERATE 0-255  $.32  CNAME  $.32.rev-32.116.10.in-addr.arpa.
$GENERATE 0-255  $.33  CNAME  $.33.rev-32.116.10.in-addr.arpa.
$GENERATE 0-255  $.34  CNAME  $.34.rev-32.116.10.in-addr.arpa.
$GENERATE 0-255  $.35  CNAME  $.35.rev-32.116.10.in-addr.arpa.

4 $GENERATE statements :|
but only one zone to delegate :)

As you noted, though, you're having a problem with dynamic updates.
Note that this would work fine if you were using the ISC 'dhcpd' which
allows you to specify the zone(s) to update when doing DDNS.


Delegation way:

You could delegate each subnet value as a separate zone.  This is
equivalent to the method of delegating each address when doing a ClassC
classless delegation.  Seems kludgy and we're going the opposite
direction from reducing delegations and zones whereas you originally
wanted to
  "work out a way of reducing the number of zones.
  "
You could end up with 256 delegations !!


;;$ORIGIN 116.10.in-addr.arpa.
   ...
$GENERATE 32-35  IN NS  whatever32.blah.
   ...
1 $GENERATE statement :)
but generates 4 delegations :|

-------------------------------------------------
Tks        | <mailto:BVance at sbm.com>
BV         | <mailto:BobVance at alumni.caltech.edu>
Sr. Technical Consultant,  SBM, A Gates/Arrow Co.
Vox 770-623-3430           11455 Lakefield Dr.
Fax 770-623-3429           Duluth, GA 30097-1511
=================================================





-----Original Message-----
From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org]On
Behalf Of Peter Anderson
Sent: Wednesday, March 14, 2001 10:22 PM
To: Mark.Andrews at nominum.com
Cc: comp-protocols-dns-bind at moderators.isc.org
Subject: RE: Classless Reverse zones



Hi ,

I was originally thinking maybe I could create a static zone
116.10.in-addr.arpa and then have n.116.10.in-addr.arpa zone which would
cover the subnet 10.116.32.0/22 (ie 10.116.32.1 - 10.116.35.254).

I started off calling that zone 22/40.116.10.in-addr.arpa.

Trouble is when a W2K updates it gets the SOA rec to work out which zone
to
update.

The other trouble was I couldn't get the nameserver to recognise for
example
that for 10.116.43.1 to update zone 22/40.116.10.in-addr.arpa not
116.10.in-addr.arpa.

Is this just not possible?

I guess the other way around would be to make 116.10.in-addr.arpa
dynamic
and then define as many other static class C reverse zones separate to
that.

Regards,

Peter Anderson
Senior Communications Analyst
<Remove ETER from my address to reply>

Any views or opinions presented are solely those of the author and do
not necessarily represent those of Westpac Banking Corporation.


-----Original Message-----
From: Mark.Andrews at nominum.com [mailto:Mark.Andrews at nominum.com]
Sent: Thursday, March 15, 2001 1:27 PM
To: panderson at westpac.com.au
Cc: comp-protocols-dns-bind at moderators.isc.org
Subject: Re: Classless Reverse zones



	Classless IN-ADDR using CNAMES is for cases where you can't
	use classic delegation techniques and don't what to delegate
	each individual reverse address.  It really shouldn't be
	used for /0-/24.
>
> Has anyone created a zone with a 22 bit (or less) mask and $GENERATE?

	Yes. You use 4 $GENERATE statements.

>
> I can't seem to get it to work and all the other examples I've found
are
for
> subsetting a class C subnet.

	That's what it was designed for.

>
> For example with a 22 bit mask do you have 4 NS recs in the parent
domain?

	Normally it's 4 consecutive, bit aligned, NS RRsets.

>
> This is all for internal DNS setup not connected with the internet at
all
> and we're getting lots of these subnets being used for dynamic
updates,
and
> I'm trying to work out a way of reducing the number of zones.

	I think you have enough information to do that if you still
	want to.

	Mark
>
> Thanks,
>
> Peter Anderson
> Senior Communications Analyst
> <Remove ETER from my address to reply>
>
> Any views or opinions presented are solely those of the author and do
not
> necessarily represent those of Westpac Banking Corporation.
>
>
> --
> Posted from mail.westpac.com.au [203.24.6.110]
> via Mailgate.ORG Server - http://www.Mailgate.ORG
>
--
Mark Andrews, Nominum Inc.
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET:
Mark.Andrews at nominum.com