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A DNS server is a DNS (Domain Name System) server that is responsible for matching Internet domain names with the IP addresses of computers on which these domains are physically located. DNS servers allow users to type regular website addresses into a browser and eliminate the need to remember IP addresses.
What is a DNS server in simple terms?
The Internet is a huge number of sites located on physically existing computers and servers. Each of these machines has a unique identifier on the world wide web – an IP address. It consists of four groups of numbers separated by dots. To open a site, you need to contact the server on which it is located by IP address. In relation to ordinary users, this looks unrealistic. Every day, many of us visit dozens and hundreds of sites – and it is absolutely impossible to allow us to memorize dozens and hundreds of sequences of numbers. They thought about this problem for a long time, and back in the 80s they developed its solution – the domain name system, or DNS (Domain Name System).
The servers included in the DNS store special correspondence tables. Domain names, that is, the alphabetic names of websites that are familiar to everyone, are compare in them with the IP addresses of the servers on which these sites are physically locate. Uk49s Teatime Results takes place at 5:49 pm (UK time) from February to October, and 4:49 pm throughout the rest of the year. UK49s Teatime Results.
Simply put, any DNS server is something like a smartphone’s Contacts section, with people’s names mapped to their phone numbers. You do not need to remember the numbers – you just choose a person, and now you are already talking to him. DNS servers work exactly the same way! However, this is a very simplified description. If we delve into the issue, we will see a lot of nuances.
How DNS Works
The Domain Name System works as follows. You decide to visit a particular site and enter its URL in the address bar of your browser. Strictly speaking, there is no node with this name on the World Wide Web – as mentioned above, it only has nodes with numeric IP addresses. That is why the first thing the browser does is access the DNS server specify in your connection settings (how to set such settings will be describe in detail later). The server, having receive a domain name, looks in the table for the corresponding IP address, and, having found it, returns it to your client device. Only after that, the browser goes directly to the site that stores the site you are interested in, and receives its content via HTTP protocol, which is displayed on your screen.
Alt – DNS
Our planet is huge, and the number of nodes on which website content is stored is incalculable. It is impossible to imagine a single DNS server that would store information about absolutely all devices containing web content. It does not need to be introduced – in fact, there are a great many DNS servers of different levels in the world, each of which is responsible only for a certain, albeit quite large, zone, and contains information only about nearby (with a certain degree of conventionality) sites. But what happens if you, for example, in Novosibirsk, decide to visit a website whose content is physically located in Rio de Janeiro?
First, the browser request will go to the DNS server specified in your local settings. There will be no match between the received Brazilian domain name and any IP address on it. Despite this, the server will not leave the request without attention – it will redirect it to a higher one, in which the necessary match may well be found. This process will be repeated as many times as needed to finally find out the IP address of the site in Rio de Janeiro. View historical France Lotto Results for the last 30 days. Check the Lotto Plus winning numbers against your tickets to see if you’re a French Lotto winner! The information received through the chain of DNS servers will return back to your browser in Novosibirsk, and it will be able to open the Brazilian site you need without any problems.
The DNS system, as we can see, is complex and intelligent – but modern browsers are no less smart. Let’s say the next day you decide to visit the same site again in sunny Brazil. Millions of browsers around the world use the cache, which significantly reduces the load on the DNS system.
The concept of a DNS zone deserves special attention. Above, we considered the relationship only between the domain name and the IP address of the site. There are, however, other objects – in particular, mail servers and site subdomains. They are directly related to the main domain name, but may well have different IP addresses. How to establish correspondence between all enumerated objects? To do this, a special file is created on the DNS server, in which they are compare. This file is a description of the DNS zone.
How to set up DNS servers
Consider setting up DNS servers using the example of one of the most common operating systems – Windows 10. Server addresses are set in the settings section dedicated to Internet access, so we are interested in it.
In the system tray (bottom right), find the Internet connection icon. Right-click on it and select “Open Network and Internet Settings”. You will see a window with numerous sections. In the “Change network settings” group, find the “Configure adapter settings” section and open it by clicking the left mouse button.
Before you is a window in which all the network connections of the computer are collect. You need to find the one through which the Internet is access. The author of this article uses a wire connection, and the corresponding icon is known as “Ethernet/Network connection”. Right-click on the icon of the active connection and select the bottom item – “Properties” in the context menu that appears.
In a new dialog box, you will see a list of components that your active connection is using. Find the line “IP version 4 (TCP / IPv4)” in it, left-click on it, and then click the “Properties” button located just below. You will see a window, which you had to get to. It is in it that the addresses of DNS servers are set (lower group of fields).
Please note that the operating system gives you two options to choose from – get the address of DNS servers automatically or use the desired addresses that you can enter manually. This option is convenient because you do not need to prescribe anything – sites should open without problems. It does, however, also have disadvantages.
If the DNS server or the provider as a whole “lies” for one reason or another, you will actually lose access to the Internet until the problem is fix – the browser will not receive the IP addresses of websites. You can get around these problems if you select the second option and manually enter the addresses of the preferred and alternative DNS server.
The question is natural: what server addresses can be specified in the settings? Here are some of the most common and popular options:
- l Google servers: preferred – 8.8.8.8, alternative – 8.8.4.4;
2. l Yandex servers: preferred – 77.88.8.8, alternative – 77.88.8.2;
3.l Yandex servers that contain records only about verified sites and protect against intruders: preferred – 77.88.8.8, alternative – 77.88.8.2;
4. l Yandex family servers (the same as in the paragraph above, minus sites with “adult” content: preferred – 77.88.8.3, alternative – 77.88.8.7;
5. l OpenDNS servers: Preferred is 208.67.222.222, Alternate is 208.67.220.220.
This is not a complete list of existing DNS servers that can be specified manually. Armed with patience, you can find other addresses on the Internet.
When finished, click the OK button and close the active connection dialog box. Check if websites open correctly in your browser.
Basic DNS records
Each DNS server contains the so-called resource records necessary for its operation. The list of main entries with a breakdown of their meanings is present below.
A: The IP address of the server where the domain is located, according to the IPv4 standard.
AAA: IP address according to the IPv6 standard.
TXT: Arbitrary text information about the domain. The length of this entry cannot exceed 255 characters.
MX: information about the mail server in the mail.company.com format. If a domain has multiple mail servers, which is not uncommon, next to each entry is a number from 0 to 65535, indicating priority (the highest is 0). It is considere standard to specify the 10th priority for the first mail server.
CNAME: The so-called canonical hostname. Required when changing the server name to redirect the request to a different domain name. Contains the Alies and Canonical name fields (the former specifies the old name, the latter specifies the new one to which the redirect should go).
Service._Proto.Name An entry consisting of multiple elements. Here Service means the name of the service (for example, ldap). Proto is the protocol for connecting clients (for example, tcp). Name is the domain name to which the service is bound. In addition, priority (similar to MX), relative weight, port number, and domain name of the service are specified.
SOA: The master record for a domain containing its name and the lifetime of information about it. It is consider the standard to indicate. The lifetime of 1 day (set in seconds, of which there are 86400 in a day).
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