Am 18.07.2014 14:28, schrieb tejas sarade: > As per the RFC 5321 when DNS lookup for recipient domain returns empty MX > records > it should try to deliver mail to A record of that domain. > > Is there any way in Postfix to disable this behaviour?
just don't do that, even don't try that not that long ago i implemented address verification in newsletter systems which did MX lookups and rejected any domain without, well it took less then 24 hours until the first customer complained why the system pretends a list of invalid addresses where they for sure know the RCPT and can prove they write and receive mails to that address whatever you think you would achieve by break RFC's is wrong that said i call anybody not add MX records even in cases the A-record points to the mailserver names, but it don't change the fact that you can't go out and fix all the stupid setups and in case you refuse to deliver mail to a specific address someobdy trying from @gmail.com with success will complain your setup is broken - and from the users point of view he is right
