Re: [DNSOP] Working Group Last Call draft-ietf-dnsop-refuse-any

[Edward Lewis <[e-mail]>]

On 11/28/16, 10:43, "DNSOP on behalf of Olafur Gudmundsson" <[e-mail] on behalf of [e-mail]> wrote:

b) pick one at “random"

Please don't use the word random, not even in quotes, in this context.  I suspect that somewhere along the line that a code writer will interpret that to mean a random number generator is needed.

Other than being potentially confusing nomenclature, answering at "random" is essentially how a cache answers type=any queries today.

Come to think of it, deciding which set is the smallest (on the wire) might be more tie consuming than just answering with the whole set - depending on what bottleneck you fear most that might be a consideration.  And predictive might also take too much thinkin'.

Caution: old fart's meandering text follows:

While I long prefer an explicit notice that the ANY query is being "shut down" answering with one (honest) set is no worse than being dumb enough to rely on asking a cache for "ANY".  If anyone is asking an authoritative for "ANY" at a name, they either can figure out they didn't get an "whole answer" (and then trawl through the expected type codes) or, well, just go trawling to start with.

I have in mind a use case where I ask a zone apex for ANY.  I should see a SOA, NS set, etc.  If not I obviously have a partial answer and then go trawl for the types I expect to see at an apex.  The code doing this has been tested and works, even identifying when one operator turned off ANY and then started it back up a month later.