Once upon a time, Stephen John Smoogen <smooge(a)gmail.com> said:
Because a lot of networks use routing tricks to send traffic to
particular
DNS server IP addresses. They may round robin, traffic route, or other
methods to send you to different DNS servers with the same ip address. Even
if they are all the same 'model' device, they have different features
turned on or are at different revisions.. so whatever you have cached is
wrong.
I'm pretty sure that's considered "their problem"... anycast servers
are
expected to behave the same (or similar enough) in terms of features
supported. Real DNS recursive servers like Unbound and BIND keep info
about particular servers by IP.
However, using info that's being tracked as a reason to not to use
multiple servers is a rather weak argument... keeping track of info for
additional servers should not be difficult.
--
Chris Adams <linux(a)cmadams.net>