Yes, I entirely agree. However, clients don't see the technical side of things and a delay of 10-15 mins is a disaster to some. We have lost clients because of this 'small' delay who see email as an instant communication medium. Perhaps our arguments weren't effective enough but then that's a matter of linguists and being on the same wavelength.
We tread the fine line between delivery and responsiveness and are often found wanting but that is not our fault, given the nature of email and its potential for exploitation. At the sharp end we often argue the virues of one system against another and forget that we serve those who are for a better expression are unwashed and ignorant but that is our lot! Ho hum! Role on the pagan festivities. ---------- Original Message ---------------------------------- From: Len Conrad <[EMAIL PROTECTED]> Reply-To: [email protected] Date: Fri, 15 Dec 2006 15:39:05 -0600 > >>However do be aware of the pitfalls of greylisting > >When greylisting is done well (like postgrey or SQLgrey for postfix), >it's extremely painless, effectively invisible after the first day or two. > >And it's incredibly effective. > >For one of my high-volume clients who is implementing greylisting >only against IPs without PTR: > >%zegrep -ic "temporary failure" /var/log/maillog.0.gz >111599 >... total greylist rejects for yesterday. > >%zegrep -ic "delayed" /var/log/maillog.0.gz >628 >... greylist rejects that were retried and accepted. > >That's only 0.56%, and I bet most of them were then rejected next for >failing sender address verification. > >When I looked at the average/median greylist-delay for retried msgs, >it was very high, like several hours, another indcation that the >re-trying IPs weren't legit mailservers. Most legit mail servers will >retry within 1 hour. > >For greylisting against all IPs, the >not-retried/total-greylist-rejects %age averages about 80% across all >my IMGate clients. > >Len > > > >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/ > ________________________________________________________________ Sent via the WebMail system at wiss.co.uk 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/
