If the exchange server is doing anti-spam analysis, then can't you setup the exchange server to be a before queue content filter? This will mean that your postfix server will still do all of the RBL and recipient checks, but the 5XX series block sent by postfix will be relayed via postfix to the upstream MTA.
Of course, this means that you won't be queuing mail on your postfix server... On Tue, Mar 17, 2009 at 2:58 PM, Chris Cameron <ch...@upnix.com> wrote: > I have a Postfix server that sits in front of Exchange. Exchange has > anti-spam software running that will reject what it deems as spam. > This is creating a problem for Postfix, which accepts a message, and > tries to send it to Exchange, who then rejects it. That leaves Postfix > with an email it has to try to bounce to a (usually) non-legitimate > sender. > > It'd be nice if Exchange accepted and then silently dropped, but that > doesn't seem to be coming. So, on my part, what can I do with Postfix > to drop messages that Exchange (defined through the transport file) > rejects? > > > Thanks, > Chris > >
