I usually set name servers at an ISP, they often take 24 - 48 hours to resolve. If one has 2 separate sets of name servers (say from 2 domain parking companies) they want to send traffic to, is it possible to switch between the sets instantly without any delays?
To be clear, how do you switch
mydomain.com (ns1.nameserver1.com, ns2.nameserver1.com) to
mydomain.com (ns1.nameserver2.com, ns2.nameserver2.com) instantly?