> At 00:57 26-03-2008, Mark Andrews wrote: > > Which is not documented in any RFC despite being a good idea. > > > > It is easy to turn "MX 0 ." into "This domain doesn't support > > email" as "." is not confusable with a hostname. There is no > > reason to look up addresses records for "." > > There was an I-D, draft-delany-nullmx-00, which didn't make it to RFC status. I was aware which is why I said "RFC" not "document". > > Which could just be a misconfiguration. You still have to > > look up addresses for "dev.null". > > Yes. People still do it. Yes they do. We, the IETF, have failed them by not providing them with a clear mechanism to do what they want without bad side effects. > > > If the implicit MX rule is depreciated for IPv6, the above won't be neede > d. > > > > It's still needed to prevent the A lookup. > > It would be needed until IPv6 takes over. It will be needed even *after* IPv6 takes over. There will be lots of queries for A records long after the majority of hosts don't have A records. We need to remove the implict MX from A to prevent the A record lookups occuring as things currently stand. Mark -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: Mark_Andrews@xxxxxxx _______________________________________________ IETF mailing list IETF@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf