On Mon, 7 Apr 2008, Phil Snowdon wrote:
Why can't people correctly configure Mail and DNS correctly these days. If all legitimate mail servers had their forward and reverse DNS mapping configured correctly I could simply use the postfix reject_unknown_reverse_client_hostname, and instantly get rid of 10s of 1000's of unwanted spam messages.
So why doesn't the forward and reverse match on the Spam emails? Sure the people who look after those ranges should be following the RFCs as well? It sounds like you are picking up with something that is an indicator of spam but not an absolute marker ( Like emails with Chinese characters going to my home domain) . In which case you should be carefully running the stats to assign a score that maximises your false negatives and and minimises your false positives with the relative weighting of each depending on your site population. But if you are serious about generating false positives why don't you insist the HELO address matches as well.. -- Simon J. Lyall | Very Busy | Web: http://www.darkmere.gen.nz/ "To stay awake all night adds a day to your life" - Stilgar | eMT.