> er... what about zones w/ A & AAAA rr's and no MX's? > when I pull the A rr's, you are telling me that SMTP > stops working? That is so broken. That's exactly the issue that's being debated now: The issue of what happens when a domain has one or more AAAA records and no MX. RFC 2821 was ambiguous as to what to do in this case. 2821bis currently says that AAAAs work the same as As in this case. Several folks have expressed the opinion that this is wrong and the right thing to do is to only allow the address record fallback for A records. Othere have even gone so far as to say that fallback behavior should be deprecated and eventually phased out in favor of requiring an MX entry for SMTP transfer, although I don't believe anyone is advocating for making that change in 2821bis. You seem to be of the opinion that fallback behavior should be extended to AAAA, and you seem to be the first one to express that opinion. (I myself have no opinion on how to resolve this other than believing it has to be resolved - the present ambigiuty is unacceptable.) Ned _______________________________________________ IETF mailing list IETF@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf