In my experience, ALL the NDRs I've ever seen are useless - if mail is bad, it should be REJECTed, otherwise the system is breaking down somewhere.
Is there a way to just drop bounces on the floor? Vasya Pupkin wrote (on Thu, Jul 22, 2010 at 06:52:22PM +0400): > You of course understand that this is not possible, right? > > On Thu, Jul 22, 2010 at 6:50 PM, Wietse Venema <wie...@porcupine.org> wrote: > > Vasya Pupkin: > >> I'm doing best I can to fight spam. > > > > Then you will have to predict what mail will be rejected down-stream. > > Let me know when you solve that problem :-) > > > > Wietse > > > >> that pierced through all filters. There is no 100% way to detect spam > >> and you know that. So, some percentage will still go through and will > >> be forwarded, and possibly rejected, causing bounce to be generated. > >> > >> On Thu, Jul 22, 2010 at 6:27 PM, Wietse Venema <wie...@porcupine.org> > >> wrote: > >> > Vasya Pupkin: > >> >> Hello. > >> >> > >> >> First, I have spent two days reading articles and searching web for > >> >> solution but failed there. I am using postfix as an mx for my domains, > >> >> it accpets mail for different addresses withing my domains which is > >> >> then forwarded to other external domains, i.e. google.com and other > >> >> mail services. Mail for unknown users is rejected, many other check > >> >> are performed, but still sometimes my system acts as a backscatterer > >> >> when something like this happens: > >> >> > >> >> 1. Incoming mail passes all tests, it's coming to one of the addresses > >> >> within my domain, i.e. existing-u...@mydomain.tld > >> >> 2. Postfix then forwards mail to external domain, i.e. > >> >> myem...@mailservice.tld > >> >> 3. For some reason mailservice.tld rejects this mail, i.e. it doesn't > >> >> like it's content or size. > >> >> 4. Postfix then bounces mail to sender, which can be forged, and thus, > >> >> becoming a backscatterer. > >> >> > >> >> Is there any way to prevent postfix from sending bounces anywhere? > >> > > >> > The best conutermeasure is not to forward spam. > >> > > >> > The second-best solution requires the ability to predict if a > >> > specific message will be rejected down-stream. Let me know when > >> > you solve that, so I can add it to Postfix. > >> > > >> > ? ? ? ?Wietse > >> > > >> > > > > -- _________________________________________ Nachman Yaakov Ziskind, FSPA, LLM aw...@ziskind.us Attorney and Counselor-at-Law http://ziskind.us Economic Group Pension Services http://egps.com Actuaries and Employee Benefit Consultants
