Start by creating one BIND master DNS server with a few slave servers, and place the slaves in data centers in different geographic locations so that they don’t suffer from the same network and power problems. For this task, edit the Name Server (NS) records for your domain. NS records determin the DNS zone’s authoritative DNS servers. When there is more than one NS record the DNS queries go randomly to all servers. If one server is down, the client just sends its queries to another. NS records are usually configured at domain registrars because they have to be included in the parent DNS zone, such as .com or .net.