We need to move our Primary DNS server to another location and subnet. The primary also services dns for is own zone. For example Godaddy has all domains including the primary domain "whatever.com" configured to the primary dns server ns1.whatever.com, secondary ns2.whatever.com, third ns1.isp.com, and 4th ns2.isp.com. The ip address for ns1.whatever.com is defined by and A record in the whatever.com.zone on the current ns1.whatever.com. If I want to bring a new ns1.whatever.com online at a different location my assumption is I can bring the new ns1.whatever.com up in the new subnet and just change the A record to the new ip address on both the current ns1.whatever.com and new ns1.whatever.com and let DNS refresh accordingly.