Up until now, you might not have spent too much time considering how the internet works. And if you did, perhaps you were happy with that old quote, “Any sufficiently advanced technology is indistinguishable from magic”.

But if you’re starting a business and registering a domain name, then you might need to dig a little deeper. For example, you need to understand the domain name system, or DNS. Let’s start simple: the DNS is often likened to the phonebook of the internet, and it’s the way that browsers find out where to access website files. It’s just like how you’d look up someone’s phone number in the Yellow Pages (okay, in the 1990s).

Your DNS records must be accurate, otherwise, your website might go offline. Inaccurate records could also slow your website down, or stop you from receiving emails with your @domain email address.

Don’t worry, it’s all pretty easy to manage, and your registrar or DNS provider should provide all the tools needed for easy management of your DNS settings.

In this article, we’ll answer the question “what is DNS” and provide a complete guide to the domain name system so you can get your website running smoothly.

What is DNS?

DNS stands for Domain Name System, and it acts as the internet’s phonebook. It’s how browsers use domain names to find websites.

Domain names are the website names that people use day-to-day. When you want to search for something, you type google.com in your browser, and when you want a great business name you type Atom.com.

Domain names are easy for humans to use because they’re usually made up of common words or phrases. But computers use IP addresses to find websites: these are a series of numbers that look like 136.058.4.38. Every domain name is mapped to an IP address (or in the case of very popular websites, multiple IP addresses).

The domain name system is how your browser finds the correct IP address from the domain name.

For our younger readers, the phone book might not make much sense as an analogy, so imagine you’re making a call on your smartphone. When you search and tap “Michael” in your contacts, your smartphone uses the number mapped to his name to make the call.

Similarly, a domain name is mapped to an IP address. The DNS consists of a series of searches through which your browser finally reaches the right IP address, finds the website files, and returns them to you.

And all this happens in the blink of an eye. It’s so fast, most of us never realize how much is going on behind our browser. Let’s take a look at the whole domain name system so you can stop wondering “what is DNS” every time you visit a website…

Anatomy of the Domain Name System

Because there are so many websites and IP addresses, one phonebook isn’t enough. Instead, there’s a whole library of them. First, your browser must find the right aisle, then the right book, before finally finding the number, or IP address and returning it to you.

This means that when you make a DNS request it goes through several servers to find the exact IP address. Let’s take a look at the whole process.

Browser: The browser is the everyday program you use to browse the internet. The browser makes the DNS request (also called a DNS query) when you enter a domain name. Chrome, Safari, and Firefox are popular browsers.

Domain Name: The domain name is the website’s commonly used address, like Sqiadhelp.com. Every domain name pairs a ‘name’ (Atom) with a TLD (top-level domain) like .com, .org or .co. Here are some domain name examples with different TLDs: whitehouse.gov, harvard.edu, branch.io, aldi.de.

IP Address: The domain name is linked to an IP address, which is how your browser accesses the website’s files. The domain name system is how your browser uses the domain name to find the IP address. IPv4 addresses look like a series of numbers or more complex alphanumeric IP addresses in the IPv6 format such as 2001:0db8:85a3:0000:0000:8a2e:0370:7334.

Servers: Servers are the steps along the way that the browser uses to find the IP address.

• Recursive resolver: The recursive resolver is like the librarian who directs you where to go, and it’s the first stop your browser makes when you enter a domain name. Like a librarian, the recursive DNS server may remember the IP address from a previous request and provide it immediately. If not, it will direct the request to the next step.

Unless you deliberately make a change, your browser will use the recursive server offered by your ISP (internet service provider).

• Root nameserver: If the recursive server has not cached the IP address, it directs the query to the root nameserver. These are managed by the non-profit organization ICANN (the Internet Corporation for Assigned Names and Numbers) which manages the domain name system. The root nameserver’s role is to pass the appropriate TLD nameserver back to the recursive server.

There are 13 root servers, but multiple copies of each to provide faster querying. 

• TLD nameserver: The TLD nameserver contains all the information for particular top-level domains. There are two main types of TLD nameserver, those for generic TLDs (gTLDs) like .com, .org, or .edu and country-code TLDs (like .ru, .nl, and .de), and some, like .io are ccTLDs that get treated like a gTLD. TLD nameservers are managed by a branch of ICANN, called the Internet Assigned Numbers Authority (IANA). When a DNS request reaches the TLD nameserver, the TLD nameserver points to an authoritative nameserver.

• Authoritative nameserver: Finally, the right phonebook has been located. The authoritative nameserver contains the final information about which IP address matches the initial request and the DNS zone file.

There are many authoritative nameservers, categorized by country, region, register, and so on. Many registrars will provide an authoritative nameserver for your domain.

How DNS Works

So that’s every piece of the puzzle, and now it’s time to put them together. What happens when you make a DNS query? Here’s a step-by-step breakdown of the DNS resolution process

1. The user enters a domain name in the browser. This is the query.

2. The query goes to the recursive DNS server.

3. The recursive server contacts the authoritative DNS server. This is done by reaching the intermediary servers: the root nameserver and the TLD nameserver.

4. The authoritative server provides the IP address to the recursive server.

5. The recursive server returns the IP address to the user. The website loads in the browser. This whole process happens almost instantly, but as you can see a lot is happening behind the scenes.

What is caching in DNS?

The above process ignores one thing: caching. The recursive DNS server doesn’t forward requests to the authoritative server every time you make a DNS query. To speed up the process, recursive servers will cache or store the information received from an authoritative server for some time (this could be just a few seconds, or up to months).

Caching makes the DNS request process much more efficient. But if a website’s DNS settings are changed while the IP address is cached, it will mean the browser is sent to the wrong place and the website won’t be found. When this happens, it’s time to clear your cache to start the search from scratch.

Managing Your DNS

As a website owner, you will have to manage your DNS, but fortunately, a good domain registrar will make this easy for you. Here’s what you need to know about managing your DNS.

There are various types of DNS records attached to your domain. The most important records are:

• ‘A’ record: the main record for your DNS. A records connect your domain and your IP address.

• Subdomain record: A subdomain comes before the main domain, like “mail” in mail.google.com. You can create subdomain records for your domain through DNS settings.

• CNAME record: CNAME records are another way of creating a subdomain, adding a prefix before your main domain. Unlike a subdomain record, which can be an A record pointing to an IP address, a CNAME record can only point to a URL. For example, you could set up blog.yourwebsite.com and link this domain to your blog elsewhere.

• MX record: MX records manage emails associated with the domain.

Managing your DNS is essentially the management of these records. Here’s what you might do.

• Add, edit, or delete records: for example, if you’re creating a subdomain.

• Set your TTL (Time-to-Live). Your TTL tells the recursive server how long it should hold information in the cache. The default is often one hour, and if you set it for too long, the recursive server won’t find your website if your DNS records change.

• Change nameservers: you can move your DNS records from one nameserver to another if you’re changing provider.

Troubleshooting DNS Issues

I wouldn’t recommend messing with your DNS settings unless you understand the consequences, but it might be necessary to manage your email accounts and set up subdomains for a blog or store.

And sometimes, things go wrong. If there’s an error with your DNS records then your website can disappear from the internet, so let’s see how to troubleshoot common DNS issues.

• Your website won’t load: If your website isn’t loading and the browser returns a page saying “www.website.com’s server IP address could not be found.” then there may be a problem with your A records. Your A record will also tell you who your web hosting provider is and they can help troubleshoot further.

Check also whether your website loads with or without the www prefix. If the www prefix doesn’t work, you need to add a CNAME record to your zone file.

• Your emails won’t send: A problem with your MX records can stop your emails from being sent or new emails from being received at your address. Check your MX records and revert them to match your provider’s recommended settings.

• DNS propagation delays: DNS propagation refers to the time it takes for changes in DNS records to be reflected across all servers. Typically, this can take up to 48 hours, and your website may be down for some of this time. DNS propagation delays can be caused if servers are caching your zone file for too long, so reduce your TTL if you’re experiencing problems.

When you make changes to your DNS records, you can use whatsmydns.net to check your DNS propagation has been successful.

• Check your domain hasn’t expired: While this isn’t a DNS issue, if your domain registration expires your website will stop working and your emails won’t get through.

Wrapping Up

Now you know the answer to the question “what is DNS” you can launch your business’s website without fear of any complicated internet shenanigans. The domain name system is no more mysterious than a big virtual library housing the records of where to find a website.

The first step towards a website is choosing the perfect domain name for your brand. 

Atom’s Premium Marketplace is where you can find one. These domains have been created by our community of naming experts around the world, and every name in our marketplace has been chosen for its brandable character and paired with a trusted top-level domain.

Your business journey can start today with a powerful domain name from Atom.