The registrar asks for DNS server names. but does not ask for an IP. How does he know about IP?

Question

Domain Name System

Example - I connect the domain to hosting, and the domain registrar asks for server names. Hosting provided, but how does the registrar know what is the IP address of DNS hosting? What will the Registrar do? To whom will he give information about server names?

Answer 1

Bruto , it's simple.
1. When you register a domain, no NS servers need to be reported. Domain status will be: REGISTERED, NOT DELEGATED.
2. NS-server is needed if you raise some service on the domain (website, mail, etc.), then you need to DELEGATE it to the hosting (to the IP address).
- if you are using a third-party DNS server, simply enter its name in the registrar panel. No IP address is needed for this DNS server, it is simply determined by nslookup or dig.
- if you use your DNS server in the same domain that you are delegating, then you need to specify both the name of the DNS server and its IP-the address. Because both the domain and the DNS server are delegated at the same time, so there is no way to find out the IP address of the DNS server.
That is, when delegating the bbb.com domain and the ns.bbb.com DNS server (it is located in the delegated domain itself), you must specify both the name and IP. And when delegating the bbb.com domain and the Cloudflare DNS server amanda.cloudflare.com , you only need to specify the name of the DNS server. The IP address where the domain will be hosted is already registered on this amanda.cloudflare.com server . PS: The number of DNS servers during domain delegation (and whether they should be in different class C subnets) is determined by the regulations for the zone. It is different for ru/com/org and so on.

Answer 2

How the DNS system works. Each domain zone has a root zone, a server that stores ns records for that zone for each domain in that zone. That is, the addresses of the DNS servers of this domain, where the rest of the DNS records are stored.
When your mail server sends mail to some domain, it sends a request to the root zone, asking where to find the domain records, then it will find out on the specified servers what MX record the domain has, where to send the letter. When you open a site, the browser looks for an A record in the same way, which will indicate the IP address of the server where the site is located.
When you connect hosting, most often the host asks you to register your ns records so that they have DNS control. This allows him to have access to them and automatically configure the site mail and the rest. Of the shortcomings of this method is that all settings, mail, etc., fly off at the same time. There is a second way, without changing the ns records and keeping the existing ones, register the site on the hosting through the A, AAAA, CNAME records. With this option, all settings are saved. But the hoster will not have access, and for example, when changing IP addresses on servers, you will have to change it yourself

Answer 3

This video also helped . Here is practice.