Classless Reverse zones

Mark.Andrews at nominum.com Mark.Andrews at nominum.com
Fri Mar 16 01:17:41 UTC 2001


> 
> >Normally it's 4 consecutive, bit aligned, NS RRsets.
> 
> What in the heck does that mean?  :)

	0,1,2,3, are bit aligned, 1,2,3,4 are not.
> 
> 
> >It really shouldn't be used for /0-/24.
> 
> Why is that?
> I was thinking that it would be used anytime you want to delegate on
> *non-octet* boundaries, not just sub "Class C".  The reverse lookup is
> based on the octets, so if there is a split in authority in *any* of the
> octets, then CNAMEs could be used to point to the correct zones.
> Am I wrong?

	No.  Normally you delegate out the /24's or /16's that make up the
	the IN-ADDR.ARPA CIDR block.

	Mark
> 
> 
> -------------------------------------------------
> 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 Mark.Andrews at nominum.com
> Sent: Wednesday, March 14, 2001 9:27 PM
> To: "Peter Anderson"
> 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
> 
> 
> 
--
Mark Andrews, Nominum Inc.
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark.Andrews at nominum.com


More information about the bind-users mailing list