Alex Williams
Alex Williams  —

Last updated:

Share this Post

DNS-cacheThe Internet is a giant black screen filled with green 0’s and 1’s.

So, DNS servers bridge the gap, letting visitors access web pages without having to think like a machine.

Table of Contents


Function of DNS Servers

It’s much simpler to recall a domain’s URL (such as hostingdata.co.uk) than it is to remember the website’s full IP address 35.246.17.50. So, to access a website like HostingData, it’s much simpler for you to enter in the URL hostingdata.co.uk.

But there are two sides to the story, with computers/ network systems not doing very well at locating each other on the internet when using domain names. 

Device-to-device, communication is far easier and accurate when done via IP addresses, which is the numerical pinpoint of where each server in the network (internet) the webpage lives on.

In short, a DNS server links URL names to IP addresses. Let’s talk about how this works, but before this, here are some of the other guides that you might find useful: 



What Is a Server?

bester Webhosting-ServerA server is a program/device dedicated to serving other programs, which we call ‘clients’ (like ‘customers’). Specifically, DNS clients come inbuilt with most desktop and mobile operating systems, so that web browsers can communicate with DNS root servers. 

As mentioned in the introduction, this type of bridging helps us to not have to think like a machine, by not having to deal with IP addresses on the front end.


What Is a Primary and Secondary DNS Server?

A primary DNS server is the first base for a browser searching where to find the site. The server stores what we call the controlling zone file. And this file contains DNS data for the domain request, which includes this IP address and other administrative elements. 

This includes the Time to Live (TTL), which dictates the time interval (seconds) that the DNS record for a website stays valid in local cache. Once the Stena server feeds back the IP address of the domain request to the browser, the query is resolved.

Secondary DNS servers aren’t mandatory for DNS systems to function, but are recommended because they hold recent copies of initial DNS records (which may not be available in the event of a cyber attack, hardware malfunction, power outage, or some other reason).

DNS Root Servers

13 foundational DNS root servers exist on the internet, made for storing full database records of domain names and their associated public IP addresses. 

If you’re old enough to remember, you can think of these as a “Yellow Pages” directory.

Names are even stored within these keystone DNS servers by using alphabetical letterings, from A to M (ie. the first 13 letters of the alphabet), with several locations mostly in the US and a few in Europe/Asia.

Because they are so important, we call them DNS root servers.


How Do DNS Servers Resolve DNS Queries?

Each time you enter a web address to your browser address bar and hit Enter, a DNS server sets about figuring out the location of the address you want to visit.

This happens by the server sending a DNS query to a number of servers, each responsible for translating a different part of the dough name name you search for. 

Four servers are queried:

  • ☑️ DNS Resolver: Resolves IP addresses location.
  • ☑️ Route Server: Receives the first request, learns the top-level domain (.com or .net, etc).
  • ☑️ TLD Server: Spits out the authoritative name server.
  • ☑️ Authoritative Name Server: The actual IP is determined. 

Then, the website displays in your web browser. But, is this always the case? 

No, the reason for a cache is so that you don’t need to go through all steps each time you visit the same website, although this all happens quickly regardless.


Best DNS Servers (Top 3)

While your internet service provider chooses your DNS server, you do not have to use them. For added speed/security, you can use an alternative. 

Here are the top 3 best DNS servers that we like:

#1 Cloudflare DNS 

Cloudflare DNS is an enterprise-grade DNS provided leading-edge response times, 100% uptime, and resistance against DDoS attacks. Though also data centres in over 200 cities around the world, giving unparalleled redundancy.

cloudflare dns

#2 Google Public DNS

Google offers free, global DNS resolutions. Switch from your ISP’s choice to this fast web browsing booster using: Load balancing, global data centres, provisioning servers, and anti amplification/DDoS safeguards. (Know however, there isn’t in a family-friendly, web filtering option)

#3 OpenDNS

With over 90 million users, this is one of the most popular free DNS services: 100% uptime, faster browsing and global data centres using peer-to-peer partnerships. Also has family-friendly web filtering safeguards (unlike Google Public DNS).

opendns


What Is DNS Caching?

Domain registration illustrationThis is a variation of resolving DNS queries using DNS servers.

This is simply the route wherein cursive resolvers resolve DNS queries, but using cached data.

After the resolver initially retrieves a website’s IP address, it gets stored in its cache for a limited period of time. 

Another client requests a domain name within that time (typically 24-48 hours), the resolver can skip the typical DNS search process and simply bring up the IP address saved in the cache.


DNS Server Malware Attacks and Failures

email-malwareDNS server-based malware attacks are common enough.

Hackles alter your settings enough that you’re rerouted to the hacker’s server (rather than Google’s DNS servers).. You’ll be sent to a replica of the target site, for instance a bank, letting the hacker harvest your valuable account information. Indeed, phishing is a cyber-risk when online trading.

(For this reason, any trusted antivirus program keeps a lookout for malware that targets DNS server settings.)

With DNS server failures, these can happen for many  reasons like cyber attacks, power outages, and hardware faults. At one point, such failures were catastrophic to operations.

But today, there’s lots of redundancies built into the DNS. At worst, there will be some delays if there are a high number of requests, because backup servers may not be as resourceful. Despite this, downtime from cyber attacks is still a major threat to e-commerce.


Conclusion

To get the best out of your DNS server, you may need to troubleshoot errors from time to time. Choosing the best DNS server service will give you the most reliable previous web browsing experience - with reduced threats from malware.

You Might Also Like: