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What is a DNS Server?

What is a DNS Server? A DNS (Domain Name System) server is a critical component of the internet that enables the translation of human-readable domain names into IP addresses. It acts as a phonebook for the internet, helping devices and computers find the correct website or service when a user types in a URL or clicks on a link.

Without DNS servers, users would have to remember complex numerical IP addresses for every website they want to visit, making the internet much less user-friendly. Instead, DNS servers take care of the behind-the-scenes translation and ensure that users can easily access the web.

DNS servers maintain a database of domain names and their corresponding IP addresses. When a user requests access to a website, the DNS server looks up the IP address associated with the domain name and directs the user’s device to the correct location.

Related Read: What is a DNS NS Record? 

Types of DNS Services

The most common types of DNS servers are:

Recursive DNS Server

A recursive DNS server is a type of DNS server that receives DNS queries from clients and then resolves them by forwarding them to another DNS server or server.

Authoritative DNS Server

An authoritative nameserver contains the definitive answer for a particular domain name. An authoritative name server can be configured to provide answers to queries different than what it receives from its upstream resolver.

Related Read: What is a DNS Record? | 8 Main Types of DNS Records 

Purpose of a DNS Server

A DNS (Domain Name System) server serves a vital purpose in the functioning of the internet. It acts as a database and directory, translating human-readable domain names into IP addresses so that users can easily access websites and online services. 

The main purpose of a DNS server is to enable users to access the web by typing in a simple and memorable domain name instead of having to remember complex numerical IP addresses.

In addition to enabling easy access to websites, DNS servers also help to distribute the load of incoming traffic, ensure redundancy and reliability, and protect against cyber threats. They maintain a database of domain names and their corresponding IP addresses and direct users to the correct location when a request is made.

In short, the purpose of a DNS server is to act as a bridge between human-readable domain names and technical IP addresses, making the internet more user-friendly and efficient for users worldwide.

Working of a DNS Server

Putting in a URL is the same as telling your computer to look up a certain IP address and establish a connection. 

To accomplish this, it makes use of the Domain Name System (DNS) server, which consists of several interconnected servers:

  • DNS recursive resolver
  • Root name servers
  • TLD nameservers
  • Authoritative nameservers

Here’s a general overview of how a DNS server works:

  • Domain Name Resolution: The first step in the DNS process is to resolve a domain name into its corresponding IP address. This is done by a client, such as a web browser or email client, when it needs to access a website or send an email.
  • Client Query: The client sends a query to its local DNS resolver, asking for the IP address of the domain it wants to access.
  • Local DNS Resolver: The local DNS resolver is responsible for checking its cache to see if it already has the information for the requested domain. If it does, it returns the IP address to the client.
  • Recursive Query: If the local DNS resolver does not have the information in its cache, it sends a recursive query to a root DNS server.
  • Root DNS Server: The root DNS server responds to the recursive query with a referral to the top-level domain (TLD) DNS server responsible for the TLD of the requested domain.
  • TLD DNS Server: The TLD DNS server responds to the query by referring to the authoritative DNS server responsible for the specific domain.
  • Authoritative DNS Server: The authoritative DNS server is responsible for maintaining the records for the specific domain. It responds to the query with the IP address of the domain.
  • Client Cache: The client cache stores the IP address of the domain it has looked up. The next time the client needs to access the same domain, it can use the cached IP address instead of going through the entire DNS process again.
  • Client Connects to Website: Finally, the client uses the IP address to connect to the website or server it wants to access, and the process is complete.

Failure of DNS Servers

Several potential causes of DNS server failure include loss of power, malicious hacking attempts, and hardware failure. When the Internet was young, problems with DNS servers might have serious consequences. 

Now, DNS has a lot of built-in redundancy, which is a huge relief. Most Internet service providers (ISPs) offer redundant recursive resolvers for their customers, and there are many copies of the root DNS servers and TLD nameservers. (Personal computer users may also employ public DNS resolvers such as Cloudflare’s 1.1.1.1.) Popular websites typically have many copies of their authoritative nameservers.

Some users may experience delays in the event of a big DNS server failure due to the volume of requests being handled by backup servers. Still, only a massive DNS outage would render a significant chunk of the Internet inaccessible. 

In 2016, when one of the largest DDoS attacks in history hit the DNS provider Dyn, this was a real occurrence. When you sign up for Cloudflare’s Managed DNS Service, you’ll also get DNS security measures designed to keep your server safe from assaults and other typical threats.

DNS Lookup vs. DNS Resolver

DNS lookup is a query to an authoritative name server for the IP address of a domain. On the other hand, the DNS resolver is software that implements the Domain Name System protocol and translates domain names into IP addresses.

The DNS protocol is currently based on TCP/IP and UDP/IP. The client sends a request to a name server via UDP or TCP. The server responds with an answer within seconds and can be used in any application that needs it.

The DNS resolver is responsible for translating human-readable URLs into numerical IP addresses that computers can understand. This service has many applications, including email delivery and web browsing.

The main difference between DNS lookup and DNS resolver is that while you can use the latter to find out whether a domain exists or not (as well as its IP address), you cannot use it to find out what type of information is hosted at that domain (for instance, if it’s an FTP server).

Final Words

What is a DNS server, you ask? It’s the backbone of the internet that allows us to access websites with ease. Simply put, a DNS (Domain Name System) server acts as the internet’s phonebook, translating domain names into IP addresses. Essentially, it’s a crucial part of the infrastructure that makes accessing online resources as simple as typing a word.

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What is DNS?

DNS stands for Domain Name System, which is a system that translates domain names into IP addresses. Domain names are the human-readable addresses that we use to identify websites, while IP addresses are the numerical addresses that computers use to communicate with each other over the internet.

When you enter a domain name into your web browser, your computer sends a request to a DNS server to look up the IP address associated with that domain name. The DNS server then returns the IP address to your computer, allowing it to connect to the website.

DNS is an essential part of how the internet works, allowing us to use easy-to-remember domain names instead of having to memorize IP addresses. It also allows websites to change their IP addresses without requiring users to update their bookmarks or remember a new IP address.

DNS – Domain Name System

DNS stands for Domain Name System. It is the internet’s phone book. It helps computers talk to each other by translating domain names into IP addresses, letters, and numbers that computers use to identify themselves on the internet.

The DNS is a server hierarchy that translates human-readable website names like “amazon.com” into computer-readable numerical addresses like “198.245.240.6”. This process is called name resolution, and it works because each server has records of all the other servers that store this information in their databases.

The DNS hierarchy can be visualized as a tree with several levels of branches that branch out from root servers at the top to leaf nodes that have no additional information beyond what is stored at their parent servers and are used only by clients that ask for more specific answers than can be found in the leaf nodes’ parent servers’ databases.

Related Read: DNS Types: DNS Query Types, Servers and Records Explained 

What is DNS Provider?

A DNS provider is the organization that hosts your Domain and utilizes Domain Name System (DNS) records to connect your Domain to email, webpages, and other web services. You can manage DNS records by accessing the DNS zone provided by your domain host. These records are vital to the operation of your website and email.

How To Check “What Is My DNS?

If you do not know where your Domain is hosted, you can find out by following the procedures:

  • Open this link in your web browser and input your domain name in the Domain area.
  • Click the DNS Lookup button below, and your domain host will be shown. 

What is Private DNS?

A private DNS server is a name server that acts as an authoritative source of information for the domain names it manages. The term “private” refers to the fact that these servers are tightly controlled by their owners rather than being offered to the public.

Private DNS servers are often used when a company wants to run its DNS infrastructure but does not want its internal customers to have access to it.

Private DNS Use Cases

The following are some possible use cases for private DNS:

  • Custom DNS Zones Within a VCN

A private zone is a subdomain of the public zone used for internal purposes. For example, if you have a company called “mycompany.com” and a separate domain called “mycompany.myprivate.com,” you can only assign the private zone to your internal network. This is useful for companies with multiple domains or subdomains for internal use only.

  • Shared Private DNS Zones Within a Region

This can be useful when only a few people need Internet access but want to keep their Internet connection private from others. In this case, they can have a shared private zone that points to another authoritative name server in a different region or even another country (although this will increase latency and throughput).

  • Split Horizon

The split horizon technique prevents looping by sending packets out of only one interface at a time. This can be accomplished with either routing protocols or DHCP snooping in software-defined networking (SDN) environments. When using DHCP snooping, you specify which interfaces will receive packets from your DHCP server and which will send them out again once they receive them back from clients connected to those interfaces.

What is Dynamic DNS?

Dynamic DNS is a software service that allows you to change the IP address assigned to your device quickly. For example, if you have an internet connection and want to access the internet from your laptop, you can use dynamic DNS to change the IP address of your device.

The advantages of using dynamic DNS include the following:

  • Your network administrators no longer need to reconfigure settings for every IP address change, allowing them to focus on the network’s health.
  • You can visit your server or website anywhere without worrying about your IP address changing. Periodically, a device on your network broadcasts your IP address to the DDNS service.
  • You will no longer have to update your records if your IP address changes manually. DDNS is more cost-effective than static DNS over time.

What is DNS Traffic?

DNS traffic is the traffic that is sent to the DNS server. The DNS server is responsible for translating the domain name into an IP address and providing it to the local computer.

Why is DNS Traffic Important?

DNS plays a crucial role in how your enterprise’s end users connect to the internet. Each connection made by client devices to a domain is recorded in the DNS logs. Examining DNS traffic between client devices and your local recursive resolver may yield a plethora of information for forensic research.

DNS inquiries can reveal the following:

  • Botnets and malware communicating with C&C servers
  • What websites an employee visit 
  • Which harmful and DGA domains were visited
  • Which dynamic domains (DynDNS) accessed DDOS assault detection, such as NXDomain?

What is DNS settings?

DNS settings refer to the records within the Domain Name System that enable users to access their websites and email accounts via their domain names. 

The DNS settings, also known as DNS records, are about the online resolution of websites and website-related services (email and FTP) and the ability to make numerous DNS adjustments using a dedicated DNS Management interface.

Typically, changing the DNS settings requires time to propagate to all root DNS servers. Repeated changes might increase this propagation time; therefore, you should only alter your domain’s DNS settings if you are confident in your abilities.

Related Read: What is a DNS Record? | 8 Main Types of DNS Records

Final Words

So, there you have it: a brief explanation of DNS that covers all of the basics. Hopefully, some of the principles here will help you understand DNS better and figure out why it’s so important.

The Internet is only possible with this essential service. So keep your eyes peeled and pay attention to what goes underneath the hood. You never know—you might use DNS someday!

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