Return-Path: X-Original-To: apmail-spamassassin-users-archive@www.apache.org Delivered-To: apmail-spamassassin-users-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id 13E4B4C65 for ; Thu, 7 Jul 2011 09:51:32 +0000 (UTC) Received: (qmail 62325 invoked by uid 500); 7 Jul 2011 09:51:28 -0000 Delivered-To: apmail-spamassassin-users-archive@spamassassin.apache.org Received: (qmail 61958 invoked by uid 500); 7 Jul 2011 09:51:18 -0000 Mailing-List: contact users-help@spamassassin.apache.org; run by ezmlm Precedence: bulk list-help: list-unsubscribe: List-Post: List-Id: Delivered-To: mailing list users@spamassassin.apache.org Received: (qmail 61951 invoked by uid 99); 7 Jul 2011 09:51:12 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Jul 2011 09:51:12 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=10.0 tests=SPF_HELO_PASS,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of uhlar@fantomas.sk designates 195.168.3.66 as permitted sender) Received: from [195.168.3.66] (HELO fantomas.fantomas.sk) (195.168.3.66) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Jul 2011 09:51:05 +0000 Received: from fantomas.fantomas.sk (uhlar@localhost [127.0.0.1]) by fantomas.fantomas.sk (8.14.3/8.14.3/Debian-9.4) with ESMTP id p679ojMF012922 for ; Thu, 7 Jul 2011 11:50:45 +0200 Received: (from uhlar@localhost) by fantomas.fantomas.sk (8.14.3/8.14.3/Submit) id p679oiTo012921 for users@spamassassin.apache.org; Thu, 7 Jul 2011 11:50:44 +0200 X-Authentication-Warning: fantomas.fantomas.sk: uhlar set sender to uhlar@fantomas.sk using -f Date: Thu, 7 Jul 2011 11:50:44 +0200 From: Matus UHLAR - fantomas To: users@spamassassin.apache.org Subject: Re: TTL and DNSBLs (was Re: SpamTips.org: Why run your own DNS server?) Message-ID: <20110707095044.GA12105@fantomas.sk> Mail-Followup-To: users@spamassassin.apache.org References: <4E1199F7.9010908@gmail.com> <4E11A960.6010305@gmail.com> <20110704092419.36e1936d@hydrogen.roaringpenguin.com> <20110705102018.GL4017@michelle1> <20110705163714.677a975b@hydrogen.roaringpenguin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20110705163714.677a975b@hydrogen.roaringpenguin.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Virus-Checked: Checked by ClamAV on apache.org >> > My experiments on real mail servers show that DNS caching is quite >> > ineffective for DNSBLs (at least for typical ones like Spamhaus that >> > use a short TTL on the order of 15-30 minutes.) >On Tue, 5 Jul 2011 12:20:18 +0200 >Michelle Konzack wrote: >> Is the TTL set global or are the TTLs set by IP? On 05.07.11 16:37, David F. Skoll wrote: >My simulation assumed the same TTL for all addresses. But that's not >relevant to cache effectiveness since most IPs are not listed in a >DNSBL (and you end up using the negative-cache-TTL.) Negative caching can be effective or in this case even ineffective too, can't it? >> I have a local bind9 which implement my private list and it set the >> TTL per target which is quiet effectiv > >If most targets are not listed, per-IP TTLs don't matter. They do, if the targets repeat. -- Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/ Warning: I wish NOT to receive e-mail advertising to this address. Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. How does cat play with mouse? cat /dev/mouse