Thanks for the reply, unfortunately the approach doesn’t seem to work for me. It appears that that the regardless of the smtp_recipient_restrictions setting, that any addresses listed in /etc/aliases addressed to $mydomain is bypassing any blocking/filtering. Is this expected behavior?
> >> On Dec 10, 2017, at 4:22 PM, Wietse Venema <wie...@porcupine.org> wrote: >> >> Omniver: >>> I have a mail server receiving internet mail for my primary domain and for a >>> few virtual domains. I'm having some spam issues with internet mail coming >>> in for address@mydomain for addresses intended for use by local >>> tools/scripts which are listed in /etc/aliases. Any ideas on how can I make >>> it that postfix accepts mail for these addressesI *only* if they were sent >>> by my mail server? >> >> A crude but simple solution: >> >> - Add the server's IP address to Postfix mynetworks. >> >> - Block some recipients if mail does not come from mynetworks: >> >> /etc/postfix/main.cf: >> smtpd_recipient_restrictions = >> permit_mynetworks >> check_recipient_access hash:/etc/postfix/recipient_access >> ... >> reject_unauth_destination >> ... >> >> /etc/postfix/recipient_access >> us...@example.com reject >> us...@example.com reject >> >> Crude because it adds the server to mynetworks. >> >> Wietse >