What is a DNS?

In the Internet there are so called. DNS serversthat have stored the database domain names with information on which server (computer) to a domain are located. At the moment, When you type into your Internet browser's Web domain address (e.g. www.nazev-domeny.cz) and the requirement to send, your computer asks one of the DNS servers on the IP address where the domain is located, connects to it and Internet browser displays the Web page.

Setting up the DNS setting is represented in DNS servers. Every domain has been assigned two or more servers,/u uses the term Czech domains with a set of servers, or a NSSET/which shall keep a record of the domain.

And records

The main records are the so-called. And records, which determine the main domain.

For example, the domain name name-domeny.

A record of the form:

@ and 123.121.123.121

means that when the domain name will be added to the browser name-domeny. en so the viewer looks up data for display on the server with the IP 123.121.123.121

Web 123.121.123.121

then it means that the given IP is looking for content for the address specified as www.nazev-domeny.cz

ftp and 123.121.123.121

by analogy, indicates the direction of the ftp record.-domeny.

MX records

DNS records can also contain other types of records, most are set up MX records for mail. You are always given priority with a server for delivery, classically, then the MX record appears on the example of name-domeny. cz as follows:

@ MX 1 mx.server.cz.

@ MX 10 mx server2. com.

@ MX 15 mx.postovniserver.cz.

In this notation, it is clear that the post office is in the first instance delivered on the site mx.server.cz, if it cannot be delivered is directed to the server which is the second in the order of priorities, in this example, mx. server2. com. and so on.

Other records

In DNS records can be edited, and other items such as the CNAME or TXT records, which are always in the process of what and where you want to move.

On the server where is the DNS record of any level goes must always be set to receive for that domain (service) that is set up as follows.

After any editing and updating records in DNS registration, the information travels over the internet, which due to the existence of the cache on local computers, servers, ISP and other transit points may all take in the order of hours, before the record is fully effective.

For more information about the operation of the DNS can be found on the open encyclopedia: