Have you apprehended of the term “domain name” while browsing the Internet? A domain name is a website address. And as of March 31, 2020, there were around 366.8 million.
Website owners need to register their domain name with the hosting company before creating and running their website at the desired URL.
But computers do not speak the same language as us, so these domain names need to be translated into something readable and compatible with the computer.
This is where the DNS server comes in.
Table of Contents
- What is a DNS server?
- How does a DNS server work?
- Why would you change your DNS?
- If your DNS server is down, what should you do?
- What are the steps of DNS lookup?
- 8 steps in DNS lookup
- What are the types of DNS queries?
What is a DNS server?
The DNS server matches domain names with IP addresses. Web domain names are friendly addresses, such as staging.thexplorion.com, and IP addresses identify each web page with a computer numeric code, such as 123.546.7.8.
What does DNS mean? You can call it the Domain Name System or the Domain Name Server.
How does a DNS server work?
All device connected to the Internet has its IP address. DNS servers use name servers, which act as a directory of IP addresses and domain names. These name servers also determine how they will map each domain name to an IP address.
A primary nameserver would be vast and inconvenient, so tons of different nameservers store this data. Also, domain names can be assigned to multiple IP addresses.
Think of it this way: many people are accessing The Techtian all the time, and each is using their device.
So when a person enters a web address, DNS compares it to an IP address that computers can interpret. This directs your link to the correct destination (the site you are trying to access).
Why would you change your DNS?
Do you know how you can change your IP address with a VPN to access content that is restricted from your geographic location? Likewise, changing the DNS hides your location.
The difference is that a VPN redirects your connection through another zone, while DNS tells the server that you are in a different place. A VPN also grants more privacy through encryption, which can also slow down the connection.
So what are some of the reasons you might like to change your DNS? Here are just a few:
- Access content on the web that is limited to your physical location (such as Netflix)
- Speed up your internet connection (sometimes independent DNS servers are faster than the default)
- Secure a safe web browsing experience for children
- Protect your devices and data through separate DNS servers with additional security features (mainly focused on anti-phishing)
- Your internet connection is cut, and you think it is a DNS problem.
If your DNS server is down, what should you do?
There are several indications that your DNS server may not be working and you will need a little work if you want to fix it. Some HTTP status codes, such as 502 error, 503 error, and 504 error, may indicate your DNS problem.
If you suspect that your DNS server is down, there are a few basic ways to confirm or even resolve the situation:
- Connect to Another Device – If you’re having trouble with just one device, while everyone can connect seamlessly, it’s probably a specific device.
- Try a new browser or window – do all devices have a problem? Open a new web browser or attempt a different web browsing application/program.
- Reset the modem and router – this can reset the entire connection, which is often all you need.
- Connect with a hardwire – plug it into your Ethernet cable to see if the problem is only Wi-Fi.
If you’re still having a problem after following the steps above (or if you get the message “DNS server not available”), it may be your DNS.
Clear DNS Cache
- Go to Applications.
- Click on Utilities.
- Double click on Terminal.
- Run the following command: sudo dscacheutil -flushcache
- If the command is prosperous, the system returns no results.
- Open a Windows command prompt.
- In the open query, type ipconfig /flushdns
- As confirmation, you should receive a success message when the cache is cleared.
Change your DNS
- Go to System Preferences.
- Click on Network.
- Click on Advanced.
- Go to the DNS tab.
- Click the + sign in the lower-left corner to add a new DNS server.
- Please enter the public DNS server (you can get them from an independent DNS server).
- Click on OK.
- Select Apply.
- Go to Network and Internet Settings.
- Click Change Adapter Settings.
- Right-click on the live network connection and select Properties.
- Left-click Internet Protocol Version 4 (TCP / IPv4) and select Properties. (If you are using IPv6, change this as well.)
- Click Use the resulting DNS server addresses: enter a new DNS server address (you can get it from third-party DNS).
What are the steps of DNS lookup?
In most situations, DNS takes care of translating the domain name to the correct IP address. Learning how these process works help to follow the DNS lookup path as it moves from the web browser, through the DNS lookup process and vice versa.
Let’s look at the steps.
Note: Often, DNS lookup information is cached locally on the querying computer or remotely in the DNS infrastructure. There are usually eight steps in DNS lookup. When DNS information is cached, steps in the DNS lookup process are skipped, making it faster.
The following example describes eight steps when nothing is cached.
8 steps in DNS lookup
- The user types “example.com” into a web browser and the query travels to the Internet and is received by a recursive DNS resolver.
- The resolver then queries the name of the DNS root server (.).
- The root server then reacts to the resolver with the top-level DNS server (TLD) (such as .com or .net), storing data for your domains. When we search for example.com, our query points to a .com TLD.
- The resolver then requests the .com TLD.
- The TLD server then replies with the IP address of the domain name server, example.com.
- Finally, the recursive solver sends a request to the domain name server.
- The example.com IP address is returned to the name server delimiter.
- The DNS resolver then matches the web browser with the IP address of the domain initially requested.
When the 8-step DNS preview returns the example.com IP address, the browser may request the web page:
9. The browser conveys an HTTP request to the IP address.
10. The server on this IP returns the web page, displayed in the browser (step 10).
What are the types of DNS queries?
In a typical DNS lookup, three types of queries occur. Using a combination of these queries, a procedure optimized for DNS resolution can reduce the distance traveled.
Ideally, the cached record data will be available, allowing the DNS name server to return a non-recursive query.
3 types of DNS requests
- Recursive query: In a recursive query, the DNS client needs a DNS server (usually a recursive DNS resolver) to respond to the client with the requested resource record or an error message if the resolver cannot find the recording.
- Iterative query: In this situation, the DNS client will allow the DNS server to return the best possible response. If the DNS server in question does not match the query’s name, it will produce a reference to the correct DNS server for the lower level of the domain namespace. The DNS client will then request a reference address. This process continues with additional DNS servers in the query chain until an error occurs or times out.
- Non-recursive query: This typically happens when a DNS resolver client queries the DNS server for a record it can access, either because it is authoritative for the record or because the record exists in its cache. A DNS server typically caches DNS records to prevent additional bandwidth consumption and load on upstream servers.