There are multiple types of DNS servers – Primary, Secondary, Authoritative, Recursive, etc. . They accomplish different functions for a network to perform properly. Specifically, DNS servers are organized, obeying a hierarchical order. Today let’s talk about the Primary DNS server and what functions it has in the system.
What’s a Primary DNS server?
The Primary DNS server is also named the Master DNS server because it is the source of the original data. The Primary DNS servers are in charge of hosting the zone files that store DNS records of the different domains.
That’s why it is so important. All the modifications, editions, eliminations can be executed only on a Master DNS server.
The Primary DNS server will be the authoritative source for the rest of the servers. Information updates will be propagated from here to the other servers through a process called a zone transfer.
Every domain has only one Master DNS server. What usually happens is that Secondary DNS servers are added for guaranteeing redundancy, up-time, and to have reliable copies of the zone data. The distinguishing feature of the Secondary DNS servers is that they don’t allow changes to the domains’ DNS records. They are only readable copies, not editable.
Besides this, the Primary DNS server has the corresponding IP addresses (records) for hostnames. Depends on the network configuration, it might be the authoritative answer to DNS clients’ queries.
How does a Primary DNS work?
As we already know, every time there’s a domain request, a translation from a human language into machine one (IP address) takes place. If example.com is requested, the IP address that its site has (126.96.36.199) must be found. The Primary DNS server store the zone file. A specific file that stores authoritative DNS information for domains, all the DNS records. IP addresses included.
The Primary DNS server is the origin of the DNS data, and it needs to spread the information with the Secondary DNS servers so they can answer DNS queries for the domain, or it must answer the queries itself to the queries.
Whenever a domain is requested, a recursive server will look for the IP address, and that will be provided by a Master DNS server or a Secondary Authoritative DNS server.
To secure the Master DNS server, it is very common practice to have Secondary Authoritative servers. They can answer with authoritative answers to the queries, and you can hide the Master DNS server, so your network is more protected.
Primary DNS server features.
The functions of a Primary DNS server are important to complete different processes. Therefore, a useful server should offer the following features.
Stability and high time availability. Considering the key role of a master server, it has to be a stable system, constantly available. Remember, all your Secondary DNS servers rely on the master’s information to work properly.
Easy access for authorized people. Yes, access must be limited to guarantee security. Only your administrator should have easy and quick access to the server to update or fix issues. The sooner these tasks can be made, the better because still some time will be required to propagate changes to the rest of the network.
Accessible for most systems of your network. We talk about internal networks. In this case, everybody should be able to access it for domain resolution in case there are no Secondary servers.
Now you know what it is and why you need a primary DNS server. When it’s about DNS or networks in general, servers are a team whose roles must be known. They work together but executing different tasks for all processes to be accomplished. The only way to leverage all their possibilities and make smart combinations is to understand their functionality.