How it Works DNS Server

   DNS servers in its implementation requires a client program that can connect each computer user with a DNS server. The program is known as the resolver. This resolver is used by application programs installed on the user's computer, such as web browsers and mail clients. Here is an overview of the process through to obtain the address of the host domain name www.microsoft.com.
From this figure can be explained the order of the workings of DNS servers on demand as follows:

• Looking for host addresses on the HOSTS file, when given the address and the process is complete.
• Looking for data made by the resolver cache to store the results of previous requests, if any store in the data cache, give the results and complete.
• Looking for the first DNS server addresses that have been specified by the user.

1. Designated DNS server will look for the domain name in its cache.
2. If not found, the search is done by looking at the domain database file (zones) which is owned by the server.
3. If not discovered, these servers will contact other DNS servers that have been associated with this server. If met store in cache and give the results.

• If the first DNS server is not found the search continued on the second DNS server and so on with the same process as above.

Domain search from a client to a DNS server is known as an iterative search process, while the search process among the domain DNS server known as recursive search.

Summary

  The existence of the DNS Server in computer networks facilitate the client computer to communicate with other computers (servers), because each IP can be created for a specific name. Before any DNS server naming performed by each client using the HOSTS file.
Domain search process on a DNS server consists of two processes that iteratively on the client and server communication between the recursive DNS server.

This apology from translite google, and more info: http://mata-cyber.blogspot.ca/2014/12/pengertian-fungsi-dan-cara-kerja-dns-server.html