[dns-operations] Name server turning off RD bit in response - just curious

[Florian Weimer]

* Craig Faasen:

> I noticed that the "rd" flag was missing from the output of a
> standard (recursive) dig against some (*) of the name-services.com
> name servers:

By the way, you should clear the RD bit when querying authoritative
servers.  Setting the RD bit increases the rate of SERVFAIL answers,
compared to queries without the RD bit.