Our postfix setup uses recipient address verification. Obviously, postfix uses for this process a special email address, defined right here.
$ /usr/sbin/postconf | grep double_bounce_sender address_verify_sender = $double_bounce_sender double_bounce_sender = double-bounce
Last week we got a problem with this setup, as our smtp asked the target
smtp about the recipient address, the target smtp on the other hand, asked our
smtp, whether email@example.com is valid, which it neglected.
So, that email could not be delivered, although both the original sender and the recipient are valid email addresses.
Now, I have different options: - deactivate address verification - create an alias for firstname.lastname@example.org, so it gets valid - set another valid email address/alias as double-bounce address
I can't forsee the outcome of these actions. Any thoughts?