When you input a specific URL into the search bar, the internet has a separate server that saves website addresses. That server is called a DNS server. A DNS server’s job is to convert what users type into their browser into information that a computer can comprehend and utilise to find a website. To put it another way, it converts a domain name like www.websitte.com into a numerical IP address like 18.104.22.168.
Domain Name System
The IP addresses of all websites are stored in the Domain Name System (DNS). DNS is responsible for establishing the right IP address for domain names such as ‘google.com’ when users type them into web browsers. The addresses are then used by browsers to communicate with source servers in order to access website information and display it to users. DNS servers, which are services that answer DNS queries, make this all possible.
A server is a device or programme that provides services to other programmes known as “clients.” Most modern desktop and mobile operating systems have DNS clients, which allow web browsers to communicate with DNS servers.
What Does a DNS Server Do?
The server’s location where the website information is saved is referred to as the IP address. When a website is sought, the browser requests the server, and the server responds with the webpage. We would have to memorise IP addresses and be forever lost on the internet if it weren’t for DNS services.
How Does a DNS Server Work?
DNS resolution is the process of converting a hostname (for example, www.websitename.com) into an IP address that a computer can understand, such as 22.214.171.124. Each Internet device is given an IP address, which is used to locate the appropriate Internet device. The procedure is very similar to how we locate our home in real life using our address.
When a user types example.com into their web browser, the entered domain address is converted into a form which can be easily comprehended by the machine.
DNS resolution is a sophisticated procedure including a number of software and hardware components that are used to access the queries. The DNS query, unlike the first, is processed by the web browser’s backend and does not involve any user intervention.
What is a Primary DNS Server?
After all, we don’t speak the same language, so we need a translator to help us with every website visit. When a query is placed, primary DNS is the principal DNS server or a nameserver that serves as the first step. The user-entered domain name is initially transferred to the primary DNS to be translated into an IP address that the system can understand.
When a user types a website’s name into a browser, the DNS server takes the entry and converts it to the domain’s IP address before connecting us. When a domain has more than one DNS server, one of them becomes the primary. The domain’s original DNS zone files are stored on the principal DNS server.
What is a Secondary DNS Server?
A secondary DNS service provides an additional set of authoritative nameservers to respond to domain queries. The information recorded on both nameservers is the same. Your domain zone file can be automatically backed up and kept as a copy on a separate server using secondary DNS.
Unexpected circumstances may cause one provider to become unavailable. In such desperate circumstances, the other will step in to answer the questions systematically. Because resolvers learn the speed patterns of the servers, they can choose the faster resource as the first point of contact for incoming queries.
Secondary DNS is a mission-critical setup that gives your domain extra redundancy by allowing you to build up a set of automatically updated zone files. This is critical for avoiding DNS outages, misconfigurations, natural disasters, and targeted attacks like distributed denial-of-service (DDoS) attacks.
What Is Dynamic DNS?
Dynamic DNS (DDNS) is a type of DNS service that automatically updates IP addresses. This is especially handy for smaller web domains (personal websites, small enterprises, etc.) that do not have static IPs and instead lease IPs from their Internet Service Provider temporarily (ISP).
Rather than making regular manual changes to a domain’s IP address via the primary server, users can utilise DDNS to automatically update their DNS records with the most recent IP address allocated to their domain.
What Are the 4 DNS Servers?
Whenever you enter a website address into your browser’s address bar and hit search, a DNS server searches for the address you wish to visit. This is accomplished by sending a DNS query to a number of servers, each of which translates a different component of the domain name you submitted. The following servers are contacted:
- DNS Recursor
The DNS recursor is a server that receives requests from client machines through applications like web browsers. The recursor is typically in charge of performing miscellaneous requests from the client to satisfy their DNS query. The role of the recursor is similar to a librarian, when requesting a website it searches for the website and brings the result.
- Root Nameserver
The root server is the phase which is responsible for converting comprehensible hostnames to numerical IP addresses. Root nameserver has the information on where the websites are located on the server and it points to their location.
- TLD Nameserver
The top-level domain server (TLD) can be compared to a particular shelf in a library. The last portion of a hostname is hosted by this nameserver, which is the following stage in searching for a specific IP address (in example.com, the TLD server is “com”).
- Authoritative Nameserver
This last nameserver functions similarly to a dictionary. It has a specific moniker that can be used to translate its definition. It is the process’s final station. If the authoritative name server has access to the requested record, it will give the DNS Recursor and the client that made the request the requested hostname’s IP address.
What Are the Types of DNS Queries?
In a regular DNS lookup, there are three types of requests. Using a mix of these queries, an effective DNS resolution mechanism can reduce the time taken for the query to reach. Cached record data will be accessible in an optimal circumstance, enabling a DNS name server to execute a non-recursive query.
There are three types of DNS queries. They are:
- Recursive Query
If the resolver is unable to locate a query, In response to a recursive query, a DNS client expects a DNS server to return the requested resource information or an error signal.
- Iterative Query
In such circumstances, an iterative query will try to allow a DNS server to offer the best possible response. The request will be routed to a DNS server for a lower level of the domain namespace if the requested DNS server cannot find a match for the query. Following that, the DNS client will seek the referral address. This process will be repeated with more DNS servers until an error instance or timeout occurs.
- Non-recursive Query
This usually happens when a DNS client requests a record from a DNS server to which it has authority, either because the DNS server is authorised to provide the record or because the record is perfectly stored on the DNS server. DNS servers usually store DNS records to save bandwidth and reduce the load on upstream systems.
Which DNS Server to Use?
Choosing the appropriate DNS servers is usually handled by the internet service providers. However, you have the option of selecting from the following options.
- Cloudflare DNS
Cloudflare DNS is a popular DNS server that transmits results in a timely manner. This DNS platform provides a 100% uptime guarantee and includes DDoS mitigation tools. Cloudflare also comes with a DNSSEC service to safeguard your software from DNS attacks.
- Google Public DNS
Google Public DNS is a well-known and free DNS server that is utilised by nearly all major Internet service providers. This DNS resolving service makes web browsing more efficient. This service employs a variety of strategies to reduce DNS search latency, including load balancing, amplification assaults, and DoS and global coverage mitigation, all of which can cause DNS servers to become overworked.
Google Public DNS, on the other hand, is purely a DNS caching service that does not filter out unwanted websites.
- Open DNS
Open DNS is one of the most popular DNS providers, with over a million users. Open DNS offers benefits such as security and efficiency. Fast internet surfing and continuous availability are provided by its global data centres. Web filtering capabilities and already configured measures are also included to keep your device (or your family’s) from browsing inappropriate websites.
Quad9 server enhances the security and privacy of your Internet Service Provider’s DNS settings. When your computer submits a DNS query, the server looks at a continually updated list of risks to prevent dangerous domain names from being looked up. This can increase performance and ensure your privacy while safeguarding your system against miscellaneous cyber attacks, phishing, leaks, and botnets.
- Comodo Secure DNS
Comodo Secure DNS is a cloud-based DNS system that provides DNS query transparency, access, and security. Comodo provides three choices. This includes protection against cyberattacks, malware, and other miscellaneous threats, as well as internet filtering for over 100 content categories, web access policy protection, and real-time visibility for devices that are connected. Premium packages include extra features such as DNS traffic encryption and can handle more queries per month.
- NeuStar UltraDNS Public
The NeuStar UltraDNS Public system is a renowned multi-level DNS system. The initial level is a free DNS resolution service that can only answer DNS queries for a certain amount of time. Users can upgrade to the higher tiers to enable security against suspicious domains and online screening for plenty of content categories.
The Verisign Public DNS server, which provides stability, security, and privacy, is the final open and public DNS server. The stability aspect is critical since it ensures that you are constantly connected and never experience downtime due to the DNS server that you are using. It neither sells nor redirects your DNS searches to third-party data harvesting firms in order to display your adverts.
- AdGuard DNS
On Windows, macOS, Android, and iOS devices, AdGuard DNS is a popular and accessible DNS server. It is well-known for blocking advertisements, but it offers much more. You may block trackers and analytics tools system-wide with the AdGuard DNS, which is always on the lookout to learn about your web browsing activities.
- DNS. Watch
DNS. Watch is a terrific third-party DNS server for anyone who wants to browse the internet without being restricted. The DNS server is entirely accessible and does not require any setup. DNS. Watch is dedicated to this objective, ensuring that you have the most unconstrained internet experience possible.
UncensoredDNS has an excellent collection of security and performance enhancement features, so you can trust it to let you surf the web freely while simultaneously protecting you from frequent assaults. The company claims that it does not log any information about users or how they use the service. Though, for a more tailored experience, the DNS server saves graphs of total inquiries.
What Does DNS Server Not Responding Mean & How to Fix It?
When a DNS server does not respond, an error message is displayed. This is usually not severe behaviour because the error can generally be corrected in one of the following methods.
- Switch to a Different Web Browser
A problem may not always indicate a DNS problem, so try switching browsers first. If switching browsers fixes the problem, make sure you’re running the most recent version of your favourite application.
- Temporarily Disable Your Firewall
If switching or updating your browser doesn’t fix the DNS server problem, the next step is to rule out your firewall as a possible reason.
Firewalls are vital for keeping your computer or device safe, but they can also cause troubles with your network connection, such as the “DNS server isn’t responding” warning.
- It’s also simple to turn them off temporarily. If your device is running Windows, go to your control panel and select Update & Security > Windows Security > Virus & Threat Protection > Manage Settings from the drop-down menu. You can deactivate your firewall from this page.
- If your device is running Mac OS, go to System Preferences > Security & Privacy > Firewall to turn it off.
The DNS server isn’t responding problem can be resolved by turning off the firewall in Mac OS.
Try accessing the same website in your browser after you’ve disabled your firewall. If the web page loads successfully, the issue is most likely the firewall. You can either modify the settings of your current antivirus application or switch to a new one in that instance.
Before proceeding to the following step, reactivate your firewall, regardless of whether the issue has been cleared.
- Restart Your Router
If turning off your firewall does not resolve the DNS server error notice, the next step is to rule out your browser.
To begin, simply press the power button twice to restart your router. This will clear the cache on your router, which should fix the “DNS server isn’t responding” problem. Try accessing the same website from your browser after turning the router back on and re-establishing an internet connection. You’re done when the web page loads successfully.
A reboot is required if this is not the case. Simply unplug the power cord and wait 30 seconds before connecting it again. Then try revisiting the site after your device has re-established an internet connection.
- Flush Your DNS Cache and Reset Your IP
If your browser, firewall, or router aren’t the issue, it could be your DNS settings. It could be your DNS cache, which saves IP addresses and other DNS records of frequently visited domains so that DNS queries can be answered faster. The DNS error warning can be resolved by flushing your DNS cache.
Depending on your device’s operating system, there are numerous options. If you’re using the most recent version of Mac OS, open Finder first. Then go to Applications > Utilities > Terminal and type sudo killall -HUP mDNSResponder in the Terminal window.
To resolve DNS errors on Mac OS X 10.11-10.15, type the command in Terminal to flush DNS.
You should receive a notice verifying that the DNS cache is reverted back to its default reset mode when entering your password. You can then try visiting the webpage in your browser once more.
DNS (Domain Name System) servers are critical for retrieving a website from a server. Without DNS, it would be impossible to access the internet. We hope you know better about DNS servers and how they function.
Experience Software Development
Don’t let the information above phase you. If you’ve landed on this page, it’s a good start. If you’re new to software development and want to learn some basic programming, register for our free 5 Day Coding Challenge through the form below. If you’ve already done the coding challenge, we do teach Python as part of our Full Stack Software Development Programme. Click here to find out more. Alternatively, if you want to try some Python, check out our Python cheat heet.