This is more of a question than a problem, I hope.
I'm migrating a server to new hardware, with some domains already migrated. I'm getting ready to migrate the domains with e-mail enabled.
I have noticed lines like these in /var/log/mail.log on the NEW server:
Mar 30 08:28:24 www3 postfix: See http://www.postfix.org/COMPATIBILITY_README.html for details
Mar 30 08:28:24 www3 postfix: To disable backwards compatibility use "postconf compatibility_level=2" and "postfix reload"
Can you please advise me?