On 25 jan 2014, at 03:10, Michele Neylon - Blacknight <michele@blacknight.com> wrote:
I'm a bit confused by your assertions with respect to authoritative DNS.
Can you please provide examples of domains where the situation you described could exist?
Eg: "target domain name. In fact, for the sake of redundancy, a domain name may have many
authoritative servers, spread around the world and also operated by different companies."
I can't see how that could work technically, but maybe I'm missing something - an example would be helpful
Let me take a step back here, because I think the confusion is a terminology issue. Using DNS-speak, an authoritative server is a name server that have the zone file. Either by having it "edited locally" (primary) or fetched using zone transfer (secondary). Both of these classes of name servers are authoritative. The alternative are caching servers, that do not store the resource record sets given back longer than the TTL on the RR-Set that is received when a query is sent either to an authoritative server or to a caching server (recursive resolver). A special set of authoritative servers are the ones NS records (in the parent zone) refer to. So, Michele, it is in fact quite normal to have more than one authoritative server. All domain names that have more than one NS record referring to it has more than one. Because of this, I do not think we disagree on functionality. We just disagree on words(*). Patrik (*) Frank Zappa on Crossfire about "words" <https://www.youtube.com/watch?v=8ISil7IHzxc>