Re: Any postfix+dspam experts out there?

[Martin Husemann <martin%duskware.de@localhost>]

On Fri, Jan 15, 2016 at 03:33:10PM +0800, Paul Goyette wrote:
> I'm trying to set up filtering ONLY on the primary (final destination) 
> mail server.  Any mail that gets sent to the backup-MX should be 
> forwarded directly to the primary, with no filtering on the backup-MX.

I would make the secondary MX the primary and do all filtering there.
Then just make it forward all mails through the tunnel to your current
primary. This is easily done via a "relay" entry in the transports file
for your domain, like:

my.do.main     relay:[abcd::n]

Of course now you must make sure to have all valid mail addresses checked
already on the new primary (I use a map with all valid names in that domain).

Martin