I just got an idea to use smtp_header_checks to discard mail from postmas...@mydomain.tld which is used for bounce emails. I hope it will work.
On Thu, Jul 22, 2010 at 6:45 PM, Randy Ramsdell <rramsd...@activedg.com> wrote: > Vasya Pupkin wrote: >> >> 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? >> > > I am dealing with the same thing. I have to forward to non-local mail > servers and I try to mimic some of those settings but we still get a few > that pass local mail to external mail which is then rejected. > Maybe a script that checks for the rejects and discards would work? I will > think through that approach for use here actually. > > RCR > Linux System Administrator > >
