DNS domain. What is DNS in simple terms. Analysis and adjustment of connection parameters

DNS, or Domain Name System, is a system that allows you to obtain information about domains. The DNS records that this tool shows are the units of transmission and storage of information on a given system.

Why should I know all this?

In order for your site to work, you need to set up DNS servers and specify the entry correctly. Incorrect DNS records can seriously undermine the performance of a site. Even if you're not an administrator, these entries will help you determine why you can't access external sites when you can easily access them from another computer.

In what format should the address be entered in this line?

In any - even "http://www.name.com", even "www.name.com" or "name.com". The service itself will determine which part of the string you entered is a domain name, and will collect the necessary data. You can even type in the address of a specific page on the site and still get the full details of the domain name. The only thing that this service does not understand is the IP addresses of sites.

"How to find out the provider's DNS server," - such a question can sometimes arise both for experienced users and for people who solve their problem with accessing the network. It may arise when it is necessary to configure Internet access through the internal network using a specific DNS server address, and not an automatically determined address. This is usually needed if there are always some difficulties with the dynamic address pool. Such a connection is more stable and allows you to set up DSL access without line breaks.

The easiest way to find out the DNS provider is to call the support service. Operators usually provide two addresses that you can enter in the network settings you configure. If for some reason this cannot be done, use our tips below.

Admin tip! If there is a problem accessing the network. Perhaps the service for determining dns addresses is not working correctly, as a result you will have a physical connection to the network, but without access to the Internet through a browser. This can be fixed by a normal reboot of the computer, advanced users can restart the service and restore the network over the http protocol.

How DNS works

The principle of operation of DNS (Domain Name Services) is well demonstrated in the illustration. The user sends the usual textual name of the site and in response receives an IP address that already provides access to a specific resource. DNS is a global network of server routers that provide daisy-chaining to a system of servers and access.

Admin tip! Ordinary users do not need to configure network settings and clarify the DNS provider and other sites. But for general development, you need to know that each text name is associated with a specific IP address, for example, 78.1.231.78.

DNS spoofing - a classic hacker attack

Experienced users will be interested to get acquainted with the scheme of servers that provide access to the Internet. A DNS server that routes user traffic is also available on the side of your provider.

Admin tip! Please note that when the DNS server is spoofed, it is possible to connect to a "fake" site. This interface is used to steal passwords and credit card information. Usually this issue is resolved by installing antivirus software that includes protection against such "traffic listening".

DNS provider

As we said, to set up a network connection, the DNS address of the provider is required. Usually there are several of them, especially for large telecommunications systems to which many users connect. Usually in the support service you can find out the primary and secondary DNS, these servers duplicate each other when there is a rather large load when users connect.

Determining the DNS provider from your network

The easiest way to do this is when there is a network and Internet access, or the same can be done from a subscriber who is also served in your provider's network. For these purposes, follow the instructions:

launch the command line by clicking on the "Start" menu, then "Run" and typing CMD (lower case) in the line;
in the command line window that opens, type ipconfig / all;
in the report you will receive a list of DNS addresses;
the received addresses can be physically registered in the network settings, in which case access to the network will work stably even if the automatic discovery of DNS servers fails.

This method helps to make network access more stable, in fact, you assign a permanent DNS server with a backup address. Both servers will route your requests on the Internet.

Screenshots

Examples are shown on screenshots. In the first case, the standard server addresses are specified. In the second case, reserve and additional. In this option, users have access to three redundant servers.

Report after running ipconfig /all command with one dns mirror

Report after running ipconfig /all command with two dns mirrors

Alternative ways to find provider DNS addresses

If you do not have access to the network, the support service does not give direct DNS addresses and you cannot get them in another way, try searching through an Internet search. This can be done using a search engine and the keywords "DNS addresses (name of your provider)". In some cases, this information may be posted on the official website of the telecommunications company or in forums by users.

Hello, dear readers of the blog site. About that, and, we already talked to you. We talked about that, and. However, there is also the technical side of the Internet, which is also very important and interesting in its own way.

So, here DNS is one of the fundamental things on which the work of the entire Internet is built. This abbreviation stands for Domain Name System, which means domain name system.

I already touched on this issue (the device of the domain name system) when I talked about that, but only in passing. Today I want to talk about the role of DNS servers in the operation of sites and the entire Internet as a whole.

Why are DNS servers needed and what is it?

The domain name system operates with fully-fledged names (Latin letters, numbers, dashes and underscores are allowed when they are formed) ..120.169.66 is not informative) and they are easier to operate.

The latter refers specifically to the human factor, because it is still more convenient for machines to use IP addresses, which they do. can get from the DNS server.

It is on these DNS servers (sometimes they are also called NS from the Name Server, i.e. name server) and the entire Internet is supported (like a flat world on three whales standing on a turtle). which does not require the direct participation of a person in its work (set it up - it plows in 24/7 mode). And there are a lot of such DNS servers on the network.

How does DNS work and what does the Hosts file have to do with it?

At the dawn of the Internet DNS didn't exist at all. But how did the network work then?.120.169.66? For this business then (and now too) the so-called was responsible, where all the hosts of the then small Internet were registered.

Such a file was (and is now) on each user's computer (it is also on yours) connected to the network (see the link above for how to find it).

In the hosts file several thousand lines were written (according to the number of sites on the Internet at that time), in each of which the IP address was first registered, and then the corresponding domain, separated by a space. This is what an entry for my blog would look like if it existed on the web twenty-five to thirty years ago:

109.120.169.66 site

Good luck to you! See you soon on the blog pages site

Let's take a closer look at what DNS is, how it works and how it works.

The Internet is an IP network and each computer on this network has a specific personal number, which is called an IP address. But since it is not convenient to use digital addressing, it was decided to use the alphabetic spelling of addresses. Therefore, when you go to any sites on the Internet, you do not enter numbers, but letters. But the problem is that computers can only perceive digital information, that is, a sequence of ones and zeros, and absolutely cannot understand alphabetic information.

That is why a special service was created on the Internet that translates letters of addresses into numbers and this service is called DNS (Domain Name System).

The DNS service is a huge database that contains information about the correspondence of a specific domain name to a specific IP address. Visually, it can be depicted as follows:

There are a huge number of domain names on the Internet and more and more every day, so you can imagine how huge the database of this service is. It is not reasonable and practically impossible to store such a large amount of information on one server.

But since the Internet network consists of subnets, it was decided to split this database and place its certain size in each of the subnets. Where there are correspondences of IP addresses to domain names only for computers included in this subnet.

What is NS server

The server that contains all the information about the correspondence of domain names in a particular subnet is called the NS server, stands for Name Server or name server. Consider an example of converting a domain name to an IP address based on a simplified network.

As you can see, this network has a computer with the alfa domain with an IP address of 192.55.11.25 and a computer with beta domains with an IP address of 192.55.11.26, and the DNS server itself, which also has the corresponding IP address. Now suppose the beta computer needs to contact the alfa computer, but it doesn't know its IP address, only its domain name. However, it knows the IP address of the DNS server to which it accesses to find out the IP address of the alfa server. The NS server searches its database and finds the IP address that matches the alfa domain name and passes it on to the beta computer. The beta computer, having received an IP address, uses it to contact the beta computer.

As you know, all domain names have their own hierarchical structure and are divided into .ru domain zones. com and others. See the material for more details. So, each domain zone has its own NS server containing information about the IP addresses of those domains that are included in a specific domain zone. Thus, this huge database is divided into smaller ones.

DNS setup

How can I change and specify DNS servers for a domain.

In order for your site to load when you enter your site address in the address bar of your browser, you need to associate the domain name of the site with the hosting. To do this, we must tell the DNS service which NS server to contact, so that it, in turn, looks in its database and tells which server (hosting) to contact the browser.

The DNS server entry looks like this:

ns1.yourhosting.ru
ns2.yourhosting.ru

You can find these addresses:

in a letter that the hosting provider sends you immediately after ordering hosting;
in the hosting control panel, for example, in the domains section;
by contacting hosting support.

Now about where they need to be specified. These DNS server addresses must be specified to the domain that you are going to use as the address of your site. Therefore, go to the website of the domain name registrar where you registered your domain. In the domain management, find the item DNS servers or Manage DNS servers / Delegation, the name may differ depending on the registrar. For example, at the domain name registrar that I use to register my domains, you need to go to the "My domains" section >> mark the desired domain and select "Change DNS servers" from the drop-down list.

After entering this section, a form will open in the fields of which you need to enter the appropriate DNS servers. To do this, in my case, you need to uncheck the box "Use registrar names" and then specify ns1.yourhosting.ru in the DNS1 field, and ns2.yourhosting.ru in the DNS2 field. IP addresses can be omitted, so some hosting providers do not issue them. After filling in the fields, click the "Edit" button.

After that, you need to wait a while until the DNS servers are matched. This can take anywhere from a few hours to a whole day. Therefore, as soon as you specify them, your site will not load.

How to specify your DNS servers for a domain

Sometimes you need to specify your own DNS servers, i.e. DNS servers that are located in the same domain. Almost everyone has their own DNS server service. In this case, for example, for this site, ns1..site is specified as the DNS server.

In doing so, the following points must be taken into account:

1. If you specify your DNS servers for a domain located in the RU, SU, RF zones, then you must specify its IP address for each DNS server. In this case, each specified IP address must differ by at least one digit; it is not allowed to indicate the same IP.

2. If the DNS servers that you specify for your domain name are in another domain, for example, if you specify DNS servers like 1ns.vash-sait.ru or 2ns.vash-sait.ru for the site domain, then you do not need to specify IP addresses .

3. If you specify your DNS servers for an international domain, then these DNS servers must be registered in advance in the international NSI Registry database. It is not possible to specify them without registration in this database. When registering with the NSI Registry, you will need to enter IP addresses for each DNS server. Therefore, when specifying DNS servers for a domain, there is no need to specify IP addresses.

Attaching an IP address to a domain

To attach an IP address to a domain, you need to go to the DNS records settings. How to do this will depend on the hosting control panel. For example, in ISPmanager you need to go to the "Domain names" section, then double-click on the required domain name and specify or edit the following three entries (to create an entry, click on the "Create" icon, to change, click on the required entry):

For the first entry, enter www in the "Name" field, select A (Internet v4 address) in the "Type" drop-down list, and enter the required IP address in the "Address" field.

For the second entry, enter @ (dog) in the "Name" field, select A (Internet v4 address) in the "Type" drop-down list, and enter the required IP address in the "Address" field.

For the third entry, enter * (asterisk) in the "Name" field, select A (Internet v4 address) in the "Type" drop-down list, and enter the desired IP address in the "Address" field.

Video: How DNS works

The material was prepared by the project:

Many owners of home PCs, laptops and tablets use the Internet without understanding the principles of its functioning at all. You can get a much more stable connection than the provider usually gives us by taking the time to study this issue. One of the possibilities to improve the comfort when using the network is to replace the default DNS address with an alternative one.

What is DNS and why is it needed

To begin with, let's figure out: what is the meaning of the letter combination DNS. The full name is Domain Name System, and translated into Russian means "domain name service". Each site on the Internet has its own domain name, we see it every day in the address bar of the browser. For example, for the well-known social network Facebook, it will look like this https://www.facebook.com. In addition, each site has its own IP address in the form of a numeric value, like this: 31.13.65.36.

DNS server translates the site's domain name into an IP address

The function of DNS is to store data about the addresses and domain names of sites. When an alphabetic request for a site name is received, the DNS server returns the numerical value of the resource address.

How to find out which DNS is provided by the ISP

If you periodically have difficulty accessing the Internet, it is better to use the setting of a specific DNS address, rather than automatic configuration. Such a connection works more stable. To do this, you need to find out the address of your provider. The easiest way is to call the operator of the organization that supplies you with the Internet service. If this is not possible, find out the DNS address using Windows tools. To do this, you need to call the command line.

You must do the following:

Open the "Start" menu, then "All Programs", on the "Accessories" tab, click "command prompt".
Enter the "Start Menu" select "Command Prompt"
Alternative way: simultaneously press the combination of the Win and R keys - in the tab that appears, type the command "cmd" and click "OK"
On the Run tab, type "cmd" and click "OK"
In the window that appears, type the command "nslookup" and press "Enter".
Type "nslookup" in Command Prompt and press "Enter"
This way you will get the provider's DNS address value.
Your ISP's IP address will appear in the Command Prompt window.

Alternative DNS servers on the Internet, overview, pros and cons

Each ISP has its own DNS service, but sometimes it makes sense to connect to an alternative server. The reasons may be different:

the provider is not able to ensure the stable operation of the DNS;
the user seeks to increase the level of protection of his computer;
PC owner wants to increase network speed;
the desire to get rid of restrictions on access to information based on territorial position.

Consider the best options and try to choose the most suitable.

Google Public DNS

The service launched in December 2009 as an experimental service. It is currently the largest public DNS service in the world, averaging over 70 billion requests per day. It uses the CDN (Content Distribution Network) method of information transfer. Google Public DNS servers support the Internet protocol IPv 6.

Video: A detailed and accessible description of installing an alternative DNS from Google

Its undeniable advantages are:

High speed - ensured by using the latest technical developments.
Reliability - obtained through the use of powerful servers and extensive infrastructure.
Security - based on the use of proprietary software.

The only negative associated with the activity of the service is the collection of data about users to earn money on advertising. This is not a serious breach of security, but potentially a disclosure of your personal information.

Open DNS

Open DNS is the largest, most trusted DNS service on the internet. It has 12 global data centers. It uses Anycast routing technology, thanks to which it responds to DNS queries faster than other providers. Websites will load faster and you won't have to worry about DNS outages depending on your ISP. Over 50 customizable filtering categories allow parents to control the websites their children visit. Open DNS blocks websites that try to steal your private information and passwords by pretending they are legitimate websites.

Video: How to set up Open DNS on your home computer

Its advantages:

Quick response to requests thanks to the use of new technologies and an extensive network of servers.
High degree of reliability achieved through the use of the latest equipment.
The ability to stop an Internet attack before it happens - the service filters traffic, it has its own database of malicious sites.
Basic features are provided free of charge.
Setup takes literally minutes.

The disadvantage is the need to register on the service.

DNS WATCH

If you need complete privacy - DNS WATCH is for you. It does not require registration and provides additional protection. No one will be able to specify which websites you should not visit. By using DNS WATCH services, you no longer need to rely on your ISP when searching the Internet. You can be sure that no DNS queries are censored. The service does not register Internet requests, you always remain an anonymous user. The only drawback is the low speed.

DNS WATCH service page providing DNS services

Norton Connect Safe

Norton ConnectSafe will protect your computer from malicious and unwanted Internet resources. Does not require installation of additional hardware and software. It is enough to enter the IP addresses of the DNS service. It is free for non-commercial use.

Video: set up protection for incoming Internet traffic, set up Norton ConnectSafe

Helps secure web browsing:

Being a product of the company Norton, which specializes in software in the field of Internet security, will put a reliable barrier on the way of malicious, fraudulent sites.
Blocks sites with explicit sexual content.
It makes it possible to restrict children from viewing sites with questionable content.

The service is not a full replacement for the anti-virus program installed on the user's computer. Norton ConnectSafe is your first layer of protection.

Level 3 DNS

The service ranks third in popularity. In addition to DNS services, it offers a large number of other products. Constantly develops new services designed to help business. An advanced DNS provider with a flexible and reliable network of servers that responds quickly to customer needs. Uses a combination of public and private connectivity options via fiber or cloud. They are combined with Layer 3 security solutions and include the required applications, services, and DNS features. Level 3 DNS allows you to create an ideal layer 3 hybrid network environment.

Description of Level 3 DNS Service Capabilities

It is necessary to take into account the fact that the service registers all requests coming from your computer.

Comodo Secure DNS

Comodo Secure DNS is a domain name resolution service that handles DNS requests through its network of redundant DNS servers. It will provide a much more reliable connection than your ISP's servers. If you choose to use Comodo Secure DNS, your PC's network settings will be changed so that all applications that access the Internet will use Comodo Secure DNS servers.

Description of the features provided to users of Comodo Secure DNS

Comodo Secure DNS gives you a safer, smarter and faster internet. He uses:

reliable server infrastructure;
a highly structured DNS system and Comodo man pages;
domain name filtering functions;
Secure DNS refers to a block list of dangerous sites.

Most of the additional features are provided for a fee.

Open NIC DNS

Non-commercial project, does not charge for access to DNS services. Completely run by volunteers, and free for users. No government can stop you from visiting your favorite sites. By starting to use OpenNIC DNS servers provided by volunteers, you can be sure that your connection will not be censored. The service has a huge network infrastructure, you can connect to the server closest to you. Simply select it from the list.

Description of the goals and policies of the Open NIC DNS service

DNS setup

After reviewing the capabilities of the services that provide their servers, choose the most suitable one, in your opinion. To configure an alternative DNS, use the table with IP addresses.

Table: IP addresses of alternative DNS servers

Service	DNS 1	DNS 2
Google Public DNS	8.8.8.8	8.8.4.4.
Open DNS	208.67.222.222	208.67.220.220
DNS WATCH	82.200.69.80	84.200.70.40
Norton Connect Safe	199.85.126.10	199.85.127.10
Level 3 DNS	209.244.0.3 4.2.2.1 4.2.2.3	209.244.0.4 4.2.2.2 4.2.2.4
Comodo Secure DNS	8.26.56.26	8.20.247.20
Open NIC DNS	Choose from the list https://servers.opennic.org	Choose from the list https://servers.opennic.org

After selecting the appropriate service, you can begin to change the DNS settings:

Hover your mouse over the "Network" icon and left-click.
The Network icon indicates the presence of an Internet connection
In the "Current Connections" tab that appears, select "Network and Sharing Center" and click the left mouse button.
Left click on "Network and Sharing Center"
In the new window, select "Local Area Connection".
On the "View Basic Network Status" tab, left-click on "Local Area Connection"
A new tab will appear, click Properties.
On the tab that appears, click "Properties"
Select "Internet Protocol Version 4 (TCP/IP 4)", click the "Properties" button again.
Select "Internet Protocol Version 4 (TCP/IP 4)" and click "Properties"
In the new tab, in the paragraph "Use the following DNS server addresses", fill in: "Preferred DNS server" and "Alternative DNS server".
Fill in the "Preferred DNS server" and "Alternative DNS server" items, click "OK"
Check "Verify settings on exit".
Click the "OK" button and restart your computer.

Common DNS Errors and How to Fix Them

There are a few common DNS errors that users encounter from time to time:

The DNS server is not responding, the DNS address of the server cannot be found.
Windows cannot contact the device or resource.
No access to DNS server.

If an error occurs, first of all, you need to check if the Internet cable has fallen out of the computer. If everything is fine, try connecting it directly, bypassing the router. If everything works without a router, try rebooting it. There are many varieties of these devices, but in general terms, the settings for all are almost the same. How to do this, consider the example of one of the models of the well-known brand TP-Link:

Enter 192.168.0.1 into the address bar of your browser and click search.
Enter the IP address of the router in the address bar of the browser
In the window that appears, enter your username and password (the default is "admin", if the password has been changed, you must remember it).
Enter your username and password correctly
Click the Login button.
In the router control panel that appears, select "System Tools".
In the menu that opens, select "System Tools"
The following window will open, in it click the "Reboot" item.
In the "System Tools" section, click "Restart"
In the next tab, the message “Press this button to reboot the device” will appear, press the button, confirm the reboot, wait.

After rebooting the router, the error should disappear. Elementary device failures happen quite often, do not rush to panic, any problem can be solved on your own.

Quite often, the cause of various DNS errors is a malfunction of the servers of your Internet service provider. If you have already taken the steps listed above, but the error message does not disappear, call your ISP, perhaps the reason lies in the incorrect operation of its DNS server.

If the provider's equipment is working, the router is working, the network is available, and the browser continues to give an error, such actions will help.