Hi guys, We're currently developing a project where customers can add their own domains to our mailsystem. The biggest problem would be that a customer adds a domain he doesn't own or isn't represented by our mail cluster. For example a customer adds ibm.com - a manual validation through one of our employees isn't possible and an automated validation makes no sense since the MX records could be changed at any time, which would force a re-check.
My thought was this: when sending the mail, configure postfix that he does a MX lookup and sends the mail to the IP given by the lookup. In this case the customer could add ibm.com, but he wouldn't be able to grab the mails sent from our cluster. I tried a few things but haven't come to a clean solution yet. Is there any way to configure postfix to always make MX record DNS lookups, or is the only way through a second postfix instance that has no localdomains specified? Thanks in advance for your time, Juergen
