Hello, I am trying to interpret two different MX lookup errors.
1) In first case Postfix generated NDR immediately and error message as follows dsn=5.4.4, status=bounced (Host or domain name not found. Name service error for name=aaa-rus.ru type=A: Host found but no data record of requested type) 2) In the second case Postfix deferred the mail and retry to deliver mail. dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for name=bbbbbb-logistic.ru type=MX: Host not found, try again) In first case it generated NDR immediately while in second case Postfix keep trying to deliver mail. What is happening behind scene?
