[dns-operations] Why would an MTA issue an ANY query instead of an MX query?

[DTNX Postmaster]

On Jun 12, 2012, at 14:46, Stephane Bortzmeyer wrote:

> On Sun, Jun 10, 2012 at 01:25:06PM +0200,
> DTNX Postmaster <postmaster at dtnx.net> wrote 
> a message of 37 lines which said:
> 
>> Google is known to be obsessed with latency, for example, so I
>> wouldn't be suprised if they deliberately request ANY and then parse
>> and cache the results for a multitude of uses.
> 
> But that's speculation. I checked the ANY requests coming into .FR
> name servers and Google (which should be an important user) does not
> appear.

We are seeing them from 74.125.0.0/16, which is a range owned by 
Google, and they resolve to '*.1e100.net', a domain owned by Google.

I do not know why they originate there; from the queries it seems that 
they may be the resolvers in use by the crawler bots, Gmail, or their
open resolvers.

I am speculating about the purpose of those requests, of course, but I 
am not making them up ;-)

Also, they seem perfectly well behaved.

Cya,
Jona