Hello, I have recently begun deploying Postfix on a web server.
Postfix is configured to handle the e-mail for the web server domain (i.e.: receives e-mail for example.com), and then has virtual tables configured to route that mail to Gmail accounts. I have mappings for all RFC required e-mail addresses (i.e.: [email protected], [email protected]), and can verify that mail sent to those addresses does go to the recipients on Gmail successfully. I have also verified that I am not an open relay. In my syslog, I can see an e-mail transaction of the following form (truncated): Feb 25 04:48:14 example postfix/qmgr[16092]: BBCE57FCD4: from=<>, size=20118, nrcpt=1 (queue active)... In this case, a sender has attempted to deliver a message with no sender (“from”), information. As far as I can tell, that is not-RFC compliant and is most likely spam. Is there a way via: smtpd_sender_restrictions in main.cf that I can block this behaviour, or is there another method of doing so ? Thank you.
