[Unbound-users] unbound 1.4.6 does not seem to have support of additional sections for NAPTR records

[Florian Weimer]

* Stephan Lagerholm:

>>There is no way to signal the absence of an AAAA RRset, so you still
>>have to make another round-trip to the DNS resolver if you're
>>IPv6-enabled and the MXes aren't.  (A and AAAA RRsets aren't cached as
>>an atomic unit.)
>
> Good point. I wonder how many MTAs that actually check that...

Exim does.  We learnt it the hard way, after seeing failures in the
field.