While it may not be good as a single test, remember that AOL bounces ALL messages without reverse DNS.
When one of our bandwidth providers screwed up our reverse DNS allocation, AOL immediately stopped accepting all e-mail from us because our IN-ADDR.ARPA records were no longer available. Once we got the bandwidth provider to re-allocate our REVERSE DNS, AOL immediately started to accept our messages again. For more information on , see: http://postmaster.aol.com/guidelines/standards.html. While AOL's connection message, sent to the mail server as mail transmission to AOL is negotiated states: "America Online (AOL) and its affiliated companies do not authorize the use of its proprietary computers and computer networks to accept, transmit, or distribute unsolicited bulk e-mail sent from the internet. Effective immediately: AOL may no longer accept connections from IP addresses which have no reverse-DNS (PTR record) assigned." The link http://postmaster.aol.com/guidelines/standards.html, in line 4 of the served page, now clearly states: "AOL's mail servers will reject connections from any IP address that does not have reverse DNS (a PTR record)." Considering that one post I saw stated that AOL was rejecting something like eight billion messages per day (please don't attack the quoted number as it may or may not be accurate), based on no reverse DNS entry, that pretty much makes it a "de-facto standard" If they are doing it, then it's going to be pretty hard for others to ignore it. Once we implemented immediate rejection for no reverse DNS entry - two years ago now, we saw our spam drop by almost 50% and have not had one single complaint since doing so. Remember, too, that for anyone to have a reverse DNS entry also requires allocation of the subnet you are using to the primary domain name of your mail server. It CAN be done. Sometimes it takes some work, but it CAN be done. There are several posts in the archive about this very issue. Bruce Barnes ChicagoNetTech Inc -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John T (Lists) Sent: Friday, December 16, 2005 19:33 To: [email protected] Subject: RE: [IMail Forum] Reverse-DNS-Check It is a good test as part of a weighting system. However, to take action on one test is not so wise. John T eServices For You > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:IMail_Forum- > [EMAIL PROTECTED] On Behalf Of Martin Schaible > Sent: Friday, December 16, 2005 5:16 PM > To: Ipswitch IMail Mailing List > Subject: [IMail Forum] Reverse-DNS-Check > > Hi, > > We do not use the reverse dns check for a spam check. I'm not sure, if > the time is > right to switch it on. In earlier days, this check was to dangerous. > > Do you use the reverse dns check? > > -- > > Mit freundlichen Grüssen > > -------------------------------------------- > Merlin Consulting > Martin Schaible > Bahnhofstrasse 27 > CH-8702 Zollikon > > Phone: +41 44 391 30 00 > Fax: +41 44 391 32 49 > > Mail: mailto:[EMAIL PROTECTED] > URL: http://www.merlinconsulting.ch > Support: http://support.merlinconsulting.ch > > GPS: N47 20.235 E8 34.226 > -------------------------------------------- > News - Neue Produkte: > > .:. NOD32 Antivirus System > .:. BlueDragon > .:. Kiwi Syslog Monitor > .:. Paessler GmbH > .:. Sawmill Loganalyzer > .:. SmarterTools > -------------------------------------------- > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: > http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
