Craig Waddington: > Hi, > > I am trying out the postscreen server - and am very impressed so far. My > original interest was in greylisting - so I have the deep protocol tests > turned on so that the temporary failure code 45x is returned for > non-whitelisted clients. > > During my testing - I noticed that the small trickle of spam that still > makes it past postscreen reattempts immediately after a 45x with no > delay, whereas genuine mail will wait at least a few minutes before > reattempting after a 45x. > > So - my question - do we know if it will be possible to enforce a delay > after the 45x before a reconnect is accepted? I have seen references to > a postcreen_greylist_threshold parameter in a postscreen strawman > document, and am wondering whether this, or some other configuration > will allow the exclusion of clients who respond instantly to a 45x?
To greylist, see: http://www.postfix.org/SMTPD_POLICY_README.html On th eother hand, making the "PASS NEW" event a trigger for a penalty time should require little new code. I added support for "penalty time" late last year but it is currently unused for lack of a "trigger" mechanism. Penalty time means the client gets 4xx replies until the penalty time expires. Penalty time after "PASS NEW" is a relatively crude mechanism compared to real greylisting, but it might do the job. Perhaps later in the year. Wietse
