[dns-operations] How does resolver query works

[Phil Regnauld]

Paul Vixie (vixie) writes:
> 
> what bind4/bind8 did and what i still think is the right thing, is to build
> the list of nameserver addresses (unrolling all the nameserver names), and
> try them in measured-RTT order, assuming 0 RTT for untried addresses, and
> depref'ing each address a little when rolling in new RTT samples.
> 
> on SERVFAIL or REFUSED, the address is poisoned (given an absurdly long
> artificial RTT) along with all other addresses that came from the same
> nameserver name.

	So what does BIND9 do ?

	Phil