We have a remote app that sends emails trough my actual POSTFIX server. Remote app is on a Azure VM where port 25 is completely blocked. My Postfix server accepts now emails from default port locally and 2525 port used to connect from Azure VM. The problem is that emails sent from Azure VM trough my POSTFIX server are not dkim signed (dkim=unknown). Any idea would be welcome. Thank you.
I set Postfix to allow post 2525.