On Thu, 17 Dec 2009, James Hess wrote: > Other tricks may be more obscure, will be less obvious that you don't > want mail, and may look like a mistake -- you might even get visitors to > your domain contacting you to report the broken MX record.
I think that's true with the suggestions in the rest of your post. > An alternative to resolving MX to an invalid IP might be to cut to the > chase and just make further DNS lookups impossible altogether... > Or for that matter delegate the subdomain to 255.255.255.255. > The recursive resolvers already have to immediately reject DNS > delegation to broadcast addresses and the like. That'll result in a SERVFAIL DNS reply which the MTA will treat as a temporary failure. Remember the aim is to get MTAs to give up on undeliverable mail immediately. 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.