Am 29.11.2012 20:46, schrieb David F. Skoll: > On Thu, 29 Nov 2012 14:36:45 -0500 > vec...@vectro.org wrote: > >> I've never had any >> complaints about delivery speed, but some senders have broken mail >> servers that don't retry on receiving a temporary failure. > > Many such servers use broken SMTP implementations that can't handle > a 4xx code in response to RCPT properly. > > We greylist after the end of DATA. This wastes bandwidth, but lets us > use the Subject: line as an additional mix in the greylisting tuple. > This catches ratware that retries in the face of greylisting, but > mutates the subject line with each retry. > > Also, once a given IP passes greylisting, we remember that and we don't > greylist that server for 40 days. If you have a large-enough user population, > this can greatly mitigate the problems caused by initial greylisting delays. > > Regards, > > David. >
greylisting isnt state of art, however it might helpfull in some domains ( everyone has its own spam), using postscreen with postfix before selective greylisting is a good choice Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer Aufsichtsratsvorsitzender: Joerg Heidrich
