When a client attempts a DNS resolution, let's say for google.com
, often multiple NS servers are returned, like:
ns2.google.com.
ns1.google.com.
ns3.google.com.
ns4.google.com.
How does a client pick one of these?
From my observations it seems to be random, but is this the default behavior (maybe as defined by some RFC)? Or does every implementation do it differently? And if so, what is the most used algorithm?