Multiple Name Servers: As described in the previous tutorial on DNS , two to seven name servers can be registered against a domain name. These are DNS servers that contain information on where to find services (such as www or email) for a particular domain name. There are two main reasons for providing more than one DNS server for each domain. The first is to provide protection against a DNS server going down- if a DNS server failed for any reason (eg. power outage, communication failure etc.) the domains using this DNS server would be unobtainable since the IP address of these domains could not be retrieved. Instead, having two or more (which should be geographically and topologically seperate) means that if a request to one of them fails, the name server can be requested again. The name servers are requested and in normal circumstances, information from any of the DNS servers is used (which normally contain the same information). The chances of two DNS servers going...