On Wed, 16 Dec 2009, Douglas Otis wrote: > > To avoid server access and hitting roots: > > host-1.example.com. IN A 192.0.2.0 > host-10.example.com. IN A 192.0.2.9 > > example.com. IN MX 0 host-1.example.com. > example.com. IN MX 90 host-10.example.com.
This is not very good from the point of view of a legitimate but mistaken sender, because their messages will be queued and retried. The advantage of pointing MX records at nonexistent hosts is most MTAs (and all common ones) will stop trying to deliver the message immediately. It is perhaps more polite to use a nonexistent name that you control, but that doesn't allow the source MTA to skip further DNS lookups, unlike the nullmx or sink.arpa ideas. Tony. -- f.anthony.n.finch <d...@dotat.at> http://dotat.at/ GERMAN BIGHT HUMBER: SOUTHWEST 5 TO 7. MODERATE OR ROUGH. SQUALLY SHOWERS. MODERATE OR GOOD.
