DNS Server Primary and Secondary Now Online.
Ti now has our own DNS servers online. With these servers we can do our own routing of domain names and with that have full control over how the name service is handled. Ti can now create VPN networks using IP numbers if need be. The Domain Name System (DNS) associates various information with domain names; most importantly, it serves as the "phone book" for the Internet by translating human-readable computer hostnames, e.g. www.example.com, into IP addresses, e.g. 208.77.188.166, which networking equipment needs to deliver information. A DNS also stores other information such as the list of mail servers that accept email for a given domain. By providing a worldwide keyword-based redirection service, the Domain Name System is an essential component of contemporary Internet use. |
The Domain Name System is maintained by a distributed database system, which uses the client-server model. The nodes of this database are the name servers. Each domain or subdomain has one or more authoritative DNS servers that publish information about that domain and the name servers of any domains subordinate to it. The top of the hierarchy is served by the root nameservers: the servers to query when looking up (resolving) a top-level domain name (TLD). The client-side of the DNS is called a DNS resolver. It is responsible for initiating and sequencing the queries that ultimately lead to a full resolution (translation) of the resource sought, e.g., translation of a domain name into an IP address.
A DNS query may be either a recursive query or a non-recursive query. The resolver (or another DNS server acting recursively on behalf of the resolver) negotiates use of recursive service using bits in the query headers.
- A non-recursive query is one in which the DNS server may provide a partial answer to the query (or give an error).
- A recursive query is one where the DNS server will fully answer the query (or give an error). DNS servers are not required to support recursive queries.
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| Resolving usually entails iterating through several name servers to find the needed information. However, some resolvers function simplistically and can communicate only with a single name server. These simple resolvers rely on a recursive query to a recursive name server to perform the work of finding information for them. |