Hi, I have a postfix-3.1.4 installation and have been given a request to block all incoming mail from all but a single specific domain and block all outgoing mail with the exception of only that same single specific domain.
Mail is received by a relay server, mail01.example.com, then forwarded to a pop/imap server, host1.example.com on the same network. We wish to reject all inbound mail with the exception of host2.example.com from being received by host1.example.com. We also wish to reject all outbound mail on host2.example.com from being sent unless it is destined for host1.example.com. host2.example.com is also using postfix-3.1.4. How would I go about doing that? I thought I could configure a check_sender_access restriction, list host2.example.com as "ok" then reject everything else: host2.example.com OK * 554 REJECT For host2.example.com, users send mail using either submission or webmail which talks to postfix on localhost/25. I believe this would be a smtpd recipient restriction?