On Sat, Oct 29, 2022 at 02:57:33PM +0200, Matus UHLAR - fantomas wrote:
> postsrsd works nicely, but if you want only SRS mail that is being forwarded
> outside, you'll need separate postfix instance for outgoing mail and apply
> postsrs there.
In many cases, just "owner-" aliases work fine, replacing the envelope
sender with a local address that won't fail SPF. Any DKIM signatures
are typically not damaged in transit through simple forwarding, so
delivery issues should be infrequent (no guarantees).
Another issue with forwarding mail is that if one's own spam filters are
more lax than the ultimate receiving system's, forwarding of inbound
spam can affect the "reputation" of one's own IP address at the
destination site. Nothing short of never forwarding spammy content can
help, in particular no amount of envelope or header rewriting solves
this.
--
Viktor.
