What is Dns Server ?

[Santosh24]

Hi,

I am not a techy. I know about hardware but I don't know much about networking. So i want to know about what is dns server ?? If anyone knows, please share the same with me ???

[Una]

DNS means Domain Name Server. A DNS server IP is used to transform a web server in a domain. There are three essential elements in Internet to make this possible.

Web server: A server that is equipped to serve web pages 24 hours a day.

Domain: The domain name quenas people seek on the Internet, entering the browser address bar.

DNS Server: It is the responsibility of transforming the IP of a web server in the domain name.

[Theodot]

DNS-server can be recursive and non-recursive. The difference in them is that recursive always return to the client response, as well as self-tracking links to other DNS-servers and questioned them, and non-recursive - returns to the client these references, and the client must own query specified server.

Recursive servers are usually used at low levels, for example, in local area networks as they cache all intermediate answers, and so on subsequent requests to him, the answers will come back faster. A non-recursive servers often are on the upper levels of the hierarchy, since they receive so many requests that the caching of responses is simply not enough any resources.

[Dammit]

In DNS-servers, we have a pretty useful feature - the ability to use the so-called Forwarders. DNS-server queries other servers independently and finds the right answer. But if your network is connected to the Internet via a slow line (eg, dial-up), then this process may take a long time. Therefore you can redirect these requests, for example, the server provider, and then simply accept his answer.

The use of "Forwarders" can be useful for large companies that have multiple networks. So in each network can be installed relatively weak DNS-server, and specify as "Forwarders" more powerful machine with a faster line. So it would appear that all responses will be cached by those more powerful server, which will accelerate the resolution of names for the entire network.

For each domain has its own database of DNS, which looks like a set of simple text files. They are located on the primary (main) DNS-server, and from time to time copy to my secondary server. And in the server configuration specifies which file contains descriptions of zones, as well as whether the server is primary or secondary for this zone.

[Mac-Imagery]

In the DNS system implemented three scenarios search IP-addresses in the database.

* A computer that needs to get a connection to another computer in the same area, sends a request to the local DNS-server for the zone to find IP-address of a remote computer. Local DNS-server that has this address in the local database of names, returns the requested IP-address of the computer that sent the request.

* A computer that needs to get a connection to a computer in another zone requests the local DNS-server of its zone. Local DNS-server detects that the desired computer is in another zone, and forms a request to the root DNS-servers. Root DNS-server goes down the tree of DNS servers and finds the appropriate local DNS-server. From him he received IP-address of the requesting computer. Then the root DNS-server sends the address to the local server, DNS, which sent the request. Local DNS-server returns the IP-address of the computer from which the request was filed. Together with the IP-address is passed the special value - the lifetime of the TTL. This value indicates the local DNS-server, how long he can keep IP-address of the remote computer in my cache. This increases the speed of processing subsequent requests.

* A computer that needs to get re-connected to a computer in another zone requests the local DNS-server of its zone. Local DNS-server checks whether the name in its cache and not run out there still value TTL. If the address is in the cache and the TTL is not expired, then the IP-address is sent to the requesting computer. This is considered unauthorized answer, because the local DNS-server believes that since the last request IP-address of the remote computer has not changed.

In all three cases the computer to search any computer on the Internet need only IP-address of the local server's DNS. Further work to find IP-address corresponding to the requested name, performs a local DNS-server. As you can see, it's now much easier for the local computer.

[blindsleeper]

The DNS server is an electronic tool, which converts the amounts expressed in letters of a domain name to a machine-understandable language.

The name server DNS stands for Domain Name Server. What we should think of the DNS server as a huge address list. Here are the questions to come, which you can enter on the address bar of different Web browsers. Special software picks out from the database the field that matches the address you entered.

In another cell of the IP address of the server database is stored, are stored on the data to be displayed on the relevant website. About the IP address that consists of numbers, the query forwarded to the appropriate place.

[Rasdasa]

The services that we can configure with DNS servers :

- We can create subdomains for each domain

- Configure your domain's primary domain and through:

• A Records
• MX Records
• TXT Records
• CNAMES

- Depending on the used DNS Manager, we will configure the domain and its subdomains with:

• URL redirects, hidden and visible
• Domain Parking
• Pages for sale
• Individual mail redirection or "catch all"