On Jul 18, 2014, at 10:52 AM, John Levine <jo...@taugh.com> wrote: >> Many years ago Joe Abley and I suggested to create a special name for >> exactly this purpose >> a name that was guaranteed to never exist in the DNS thus the first lookup >> would always return NXDOMAIN thus the A+AAAA lookups would never take place. >> http://tools.ietf.org/html/draft-jabley-sink-arpa-03 > > While I don't think it's relevant for this application, isn't that > what RFC 6761 defines "invalid" to be? > > R's, > John
John, I think it would be great to have this document use “no-mail.invalid.” as the domain name rather than “.” in the MX record i.e. foo.bar.example MX 0 no-mail.invalid. But this is just a question of preference and installed base. Olafur _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop