krb1.5 plugin interface query

[Jeffrey Hutzelman]

On Friday, September 08, 2006 03:37:33 PM -0400 Ken Raeburn 
<raeburn at mit.edu> wrote:

> (A question I haven't investigated: Does the
> presence of an A record there and no AAAA records mean there is no
> AAAA record, or would you still need to make that query?  My guess
> would be the latter.)

I believe the latter.  RFC3596 redefines query types that trigger type A 
additional section processing to also perform type AAAA additional section 
processing.  However, the server is only required to return records it 
already has, not to perform additional queries to obtain records it does 
not have.  So, it's fairly easy to construct a scenario in which A records 
are returned but AAAA records are not, even though they exist.  IMHO this 
is unfortunate, since it means that the round-trip savings realized by use 
of the additional section are lost in many cases.

-- Jeff