> -----Original Message----- > From: Ray Collazo > Sent: Friday, September 12, 2008 5:44 PM
> Malcolm: > Thanks for your opinion: In using the qpsmtpd plug in to > guess dialups to reduce junk mail, I have been able to > eliminate about 85% of junk mail that Courier was having to > deal with, and just about all virus-spreading attempts. Thus > far I have found one company whose RDNS was incorrectly set, > whom contacted me and I put them into a whitelist. You can reduce junk mail by 100% by simply prohibiting any connections. Your problem is that you seem to think your system works simply because it cuts down traffic. That's a bogus metric. The key is to figure out how much legitimate traffic you are _also_ dropping -- and I can confidently predict you have no measurements on that! Oh, and you're repeating that "incorrectly set" thing as if it were true or accurate! Your dumb system isn't testing whether there is a valid, correct RDNS entry, it's trying to assess whether the traffic is legitimate based on the entry that exists. I have a valid RDNS -- you just happen to (incorrectly) believe it's a dialup. Your belief is false -- it's a DSL line with a static IP that is specifically sold to run servers. No-one else seems to care that the valid RDNS maps to a name that's different from the DNS entry, because the server(s) behind that address handle traffic for multiple domains, anyway. > If you know of a better way to get rid of Junk Mail coming > from bots and zombies, I'm all ears. For your (evidently small) system, greylisting / port knocking and black lists do more, better. > I already tried using a few RHSBL lists, but that kept > blocking some legitamite mail so I stopped using it. Mmm... And you think this qpsmtpd junk *isn't* blocking legit mail? Here's a clue: why are we having this discussion? > Thus > far, QPSMTPD and its related plugins that I have enabled > (check_earlytalker, nodialup, check_relay, dnsbl, > check_spamhelo, check_basicheaders, check_goodrcptto, > virus/clamav) has been the greatest and most configurable > filter I've seen thus far. I'd like to configure it Better, > yes, but when foraging on ones own with little time to spare > and no budget to work with, I've got to go with what works. There's the point. It doesn't. It just appears to you to be working. > -Ray > > "<[EMAIL PROTECTED]>: > loraninc.com [216.117.220.102]: > <<< 550 Sorry, h-74-0-35-146.snfccasy.covad.net (74.0.35.146) > seems to be a > dialup: use your ISP's SMTP server, or Fix your RDNS. If you > feel you are receiving this message in error, please call us > at +1-800-544-4840" > > Is complete BS. > > Making judgements about whether or not something is a > "dialup" hasn't been a useful tool for years, even when you > got it right. In this case, you haven't, and that IP is not > a dialup (it's DSL, but as static as a T1 -- just faster). > > FWIW, the RDNS exists, and is "fixed", IAW the RFCs. So you > may want to rethink that whole idea... > > Malc. ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ courier-users mailing list [email protected] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
