System IP Address
How to remove or hide the hostnames and IP addresses of our internal systems from the messages headers before they go out to other users for security purpose
Postfix MTA can filter headers using header_check (built-in content inspection) directive. Open main.cf file, enter: # vi /etc/postfix/main.cf Now, turn on local recipient checking in the SMTP server, specify the header_checks parameter specifies an optional table with patterns: header_checks = regexp:/etc/postfix/header_checks Save and close the file. Create /etc/postfix/header_checks file, enter: # vi /etc/postfix/header_checks Ignore 127.0.0.1, [...]