Matt Corallo:
>
>
> On 8/11/21 16:52, Wietse Venema wrote:
> > If the sender address can override the routing, even if the recipient
> > would otherwise be delivered locally, then that would be a recipe
> > for mailer loops with the potential for mail explosions. This is
> > why we have sender_dependent overrides for default transports and
> > relay hosts, and avoid such stability problems.
>
> Ah! Understood, indeed, the setup I've had to fall back to has some risk of
> routing loops, though with some care to
> hopefully ensure it can't ever actually be hit. I guess the only solution is
> multi-key lookups, which would be nice, but
> understood that its likely very nontrivial to add :).
Would this do the job:
/etc/postfix/main.cf:
smtpd_sender_restrictions = hash:/etc/postfix/sender_access
/etc/postfix/sender_access
example.com filter smtp-example-com:relay-for-example-com
...
/etc/postfix/master.cf:
smtp-example-com .. .. .. .. .. .. smtp
...
It avoids the need for another instance. Postfix should break a
mailer loop that delivers to itself.
Wietse
