How to set up a domain with a separate dns server?

Question

Domain Name System

For a long time I did not deal with setting up domains, hosting. I remember when I registered a domain before and set it up, there was no need to buy a dns server separately, everything was out of the box. Today I bought a domain on a new registrar, and there, after buying a domain, when setting it up, you can buy a separate DNS server (whether or not, no idea, probably needed) In general, I bought it, in the settings I registered my domain, mail, server ip-address left the rest. That is NS-records did not change. Then he returned to the domain on the registrar. I look, there the domain in the settings also has NS records, but not my purchased DNS. From here the question is whether they need to be changed to an analogue in the settings of the purchased DNS server, or should they be left as they are, or should you just add to them those which are registered at DNS? Why are they listed there at all? Could I, like, not buy a separate DNS server and not prescribe anything if the NS records of the domain registrar are already registered there? Does this mean that the domain is tied to some registrar's DNS? I think not, since there, at least, there should have been settings for the registrar of all DNS server records, and binding to the ip address, but why are NS registered there at the domain and should NS be registered there from the purchased DNS server?

Another additional question: I read on some sites that it is possible to specify google or Yandex addresses as ip as NS records, is this so?

Answer 1

Forgot to write here. Solved the problem. It was necessary to register, as I originally did. In the NS settings of the domain registrar, register the NS records registered in the DNS server. That is, the essence is this - the domain registrar distributes information about the domain and its NS records, these NS records are registered at the DNS server, and A records with domain mapping and ip with your application are also registered there.
Why didn't it work in the first place? At the beginning I did everything right, but did not wait for the registrar to update this data apparently. Although the whois already showed the correct NS records, the site was still not available, even though I even cleared the DNS cache locally. Apparently there is somewhere else the information should be updated about these NS records. Then, without waiting for the right moment, I tried another solution and registered the IP address of the DNS server in the NS of the domain registrar, as advised here, and it seemed to me that everything worked, but by that time the first settings had just begun to work. Therefore, the next day everything stopped working again, because a day later the settings came into effect where the IP address of the DNS server was registered in the NS of the domain registrar, which is not true.
In general, you need to register the NS of your DNS in the NS domain registrar and wait.

Answer 2

From here the question is - do I need to change them to an analogue in the settings of the purchased DNS server, or do I need to leave them as they are, or do I just need to add to them those that are registered with DNS?

In the DNS settings of the registrar, it is necessary and sufficient to register an NS record that will point to the IP address of the DNS server you rented.

Why are they listed there at all?

Each zone has a server that is responsible for it. Most likely, the registrar provides a free opportunity to manage your domain's DNS records through its servers, which he actually registered in NS. Until you change the registrar's NS records to your server, no one will see your settings.

Could I, like, not buy a separate DNS server and not prescribe anything if the NS records of the domain registrar are already registered there?

Rather yes than no. Personally, I have not yet met registrars who did not provide the opportunity to manage the records of the purchased domain for free.

Does this mean that the domain is tied to some registrar's DNS? I think not, since there, at least, there should have been settings for the registrar of all DNS server records, and binding to the ip address, but why are NS registered there at the domain and should NS be registered there from the purchased DNS server?

What do you mean? The registrar informed the root servers that he had registered the domain (in many cases, you can check it using the whois service) and provided a number of administrative records like SOA, NS... Accordingly, everyone will contact the server specified in the registrar's NS record.

Another additional question, I read on some sites that it is possible to specify google or Yandex addresses as ip as NS records, is this so?

If I understand you correctly, we are talking about public DNS servers, such as Google's 8.8.8.8, this address can be specified on the client computer as the address of the DNS server from which the client computer will take data for resolving DNS names. But that is another story.
In general, since you are a "Backend software engineer", read any introductory article on the principles of DNS. It is difficult to describe this whole system within the framework of one answer.

Answer 3

Domain registration.
Two independent systems intersect here. Who owns the domain and the technical implementation of the Internet.
To answer the first question, there is a focal point database. Data is entered into it
through legal entities of intermediaries (domain registrars).
For the DNS service to work, information about the server that owns the specific information is required.
Root lists for the py zone are updated every 2 hours.
Chain.
In the registrar's office, you registered ns server(s).
After a couple of hours, they spilled over to the root DNS server
From the side of a simple user.
I want to visit such a site.
Router DNS - I don't know
the provider's DNS - I don't know
the higher one - I don't know
root - ask for this address.
and started to descend.
somewhere in the chain, the specified server can ask and give below an A record, it can consider it not royal business and answer with NS records
. In general, for the registrar, this is only the direction where the request should go.
Now the server to which you delegated .
There must be at least one dns record A . Otherwise, nothing will break.
Whether it will be your personal dns server, hoster, registrar, mail service or something else is
not important.
when delegating, specifying the ns server can be in the form of an ip address. But there are risks in case of its change. usually written in the form ns.server.ru (so that ip can also be steered)
There is a separate case when ns are directly to the domain itself
A server.ru
NS ns.server.ru
in this case must be registered at the registrar along with the ip in one line
ns.server.ru 111.111.111.111
so that there is no looping in the resolve