Re: [DNSOP] BULK RR as optional feature

Evan Hunt <> Wed, 29 March 2017 02:19 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id F2964128D2E for <>; Tue, 28 Mar 2017 19:19:38 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -6.901
X-Spam-Status: No, score=-6.901 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, RP_MATCHES_RCVD=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id h6200EjY3_7h for <>; Tue, 28 Mar 2017 19:19:37 -0700 (PDT)
Received: from ( []) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 56B7D1289B5 for <>; Tue, 28 Mar 2017 19:19:37 -0700 (PDT)
Received: from ( []) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 5FEF934930F; Wed, 29 Mar 2017 02:19:35 +0000 (UTC)
Received: by (Postfix, from userid 10292) id 54358216C1C; Wed, 29 Mar 2017 02:19:35 +0000 (UTC)
Date: Wed, 29 Mar 2017 02:19:35 +0000
From: Evan Hunt <>
To: "Woodworth, John R" <>
Cc: John Levine <>, "" <>
Message-ID: <>
References: <20170328183156.2467.qmail@ary.lan> <> <A05B583C828C614EBAD1DA920D92866BD0717CFC@PODCWMBXEX501.ctl.intranet>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <A05B583C828C614EBAD1DA920D92866BD0717CFC@PODCWMBXEX501.ctl.intranet>
User-Agent: Mutt/1.5.23 (2014-03-12)
Archived-At: <>
Subject: Re: [DNSOP] BULK RR as optional feature
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: IETF DNSOP WG mailing list <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Wed, 29 Mar 2017 02:19:39 -0000

On Wed, Mar 29, 2017 at 12:41:26AM +0000, Woodworth, John R wrote:
> I believe this would ultimately be less efficient than generating
> the records on the fly.

Unquestionably. This clearly wouldn't be the preferred behavior.
If the slave does understand BULK records, you'd just transfer

> Assuming a relatively small range, say an IPv4 /16.  You would
> need to sweep through similar logic and load _every_single_answer_
> into memory rather than just the ones which are asked for.

Sure, that's what $GENERATE does. The generated records are then transfered
normally. You con't end up with one auth server that has generated records
and another that doesn't.

> I see no reason caching couldn't be used to hold the more commonly
> requested records in order to save on CPU. (apologies for double-neg)
> Additionally, the patterns could (and most likely should) be pre-
> parsed for simpler/ lower calorie processing.

But if you have a primary that supports BULK and a secondary that doesn't,
then you have two authoritative servers for the same domain with the same
serial number but one of is saying NXDOMAIN when the other one returns a
positive answer.  This is a significant problem, and the draft ought to
address it.  (Or have I misunderstood something?)

Evan Hunt --
Internet Systems Consortium, Inc.