The domain name system (DNS) is the internet's address book. It translates the name people type, like yourbusiness.co.za, into the numeric address of the computer that holds your website, so a visitor lands in the right place without memorising a string of numbers. If you own a business website or email address, DNS is quietly working every time a customer finds you.
Most business owners never need to think about it until something breaks: the website stops loading after a move, or email suddenly bounces. Understanding the basics will save you time, money and a few panicked phone calls.
What does DNS actually do?
Every device on the internet, including the server that hosts your website, has a numeric address called an IP address. Computers find each other using those numbers. People, however, are far better at remembering names.
DNS bridges the gap. Think of it like the contacts list on your phone: you tap "Thandi" and the phone dials the number for you. In the same way, you type a domain name and DNS looks up the matching IP address.
What is the difference between a domain name and DNS?
Your domain name is the name you register, for example yourshop.co.za. DNS is the system that connects that name to your website, your email and other services. You can own a domain and still have a website that doesn't load, simply because its DNS settings point nowhere or to the wrong place.
How does a DNS lookup work, step by step?
When someone types your address into their browser, a quick chain of questions happens in a fraction of a second:
- The browser checks its memory. If the visitor has been to your site recently, the answer may already be stored on their device.
- The request goes to a recursive resolver. This is a DNS server, usually run by the visitor's internet provider or a public service, that does the searching on their behalf.
- The resolver asks a root server. Root servers don't know your address, but they know who looks after each ending, such as .com or .za.
- The resolver asks the registry for the ending. For .co.za names, this points towards the servers responsible for the co.za space.
- The resolver asks your authoritative name servers. These are the servers that hold your DNS records, and they give the final answer: the IP address.
- The browser connects to that address and your website appears.
The answer is then stored (cached) for a while so the next visitor gets it faster.
What are DNS records?
DNS records are the individual instructions stored for your domain. You don't need to memorise them, but you should recognise the main ones:
| Record | What it does | Plain-English example |
|---|---|---|
| A | Points your domain to an IPv4 address | "yourshop.co.za lives at this server" |
| AAAA | Points your domain to an IPv6 address | The same, using the newer address format |
| CNAME | Makes one name an alias of another | "www" follows your main domain |
| MX | Says where your email should be delivered | "Send mail for this domain to this mail server" |
| TXT | Holds text used to verify and protect the domain | Email security settings and ownership checks |
| NS | Lists the name servers in charge of your DNS | "These servers hold the records" |
Why do MX and TXT records matter for email?
If your business emails land in spam or never arrive, the cause is very often a missing or incorrect MX or TXT record. Email security settings such as SPF, DKIM and DMARC are published as TXT records, and mail providers use them to decide whether a message really came from you. Whenever you change your hosting or email provider, check these records.
What are name servers?
Name servers are the computers that store and serve your DNS records. When you register a domain, you tell the registry which name servers are in charge of it. Your hosting company usually gives you two or more name server addresses, which look like ns1.example.com and ns2.example.com.
Changing a domain's name servers hands control of all its DNS records to a different provider. Changing a single record, on the other hand, only affects that one service. This distinction matters when you move your website but keep your email where it is.
What is DNS propagation, and why does it take time?
When you change a DNS record, the update does not reach the whole internet instantly. Resolvers around the world keep a saved copy of your old answer for a set time, called the TTL (time to live). Until those copies expire, some visitors may still see the old site while others see the new one.
This is why a website move can look "half done" for a few hours. In many cases changes show up quickly, but it can take up to 24 to 48 hours for everyone to see the same thing. Practical tips:
- Make DNS changes at a quiet time for your business, not during a sale or campaign.
- Lower the TTL a day or two before a planned move if your DNS provider allows it.
- Don't keep editing records while you wait. Each change restarts the waiting game.
- Test from a phone on mobile data as well as your office Wi-Fi, since each may use a different resolver.
Why should a South African business owner care about DNS?
A few real-world situations where DNS knowledge pays off:
- Moving your website. A new host means new name servers or a new A record. Knowing which one to change prevents downtime.
- Setting up business email. Email only works properly when your MX and TXT records are correct.
- Connecting other services. Booking systems, online shops and email marketing tools often ask you to add a CNAME or TXT record to prove you own your domain.
- Protecting your brand. If someone else gains access to your domain account, they could change your DNS and redirect your customers. Use a strong, unique password and keep your registrant details up to date.
- Keeping the domain alive. If a domain expires, its DNS stops working and your website and email go dark. eStart's current .co.za renewal price is R85 per year, so it is worth setting a reminder.
Do you have to manage DNS yourself?
Not necessarily. Many small businesses simply use the DNS settings provided with their hosting and never touch them. That is a perfectly sensible approach if your website and email are all with one provider. You only need to get hands-on when you split services between providers, or when you move.
If you do edit records yourself, follow these safe habits:
- Write down or screenshot the existing records before changing anything.
- Change one thing at a time.
- Don't delete records you don't recognise, since they may be keeping your email working.
- Ask your provider for help if something doesn't load after the expected waiting time.
Frequently asked questions
What is the domain name system in simple terms?
It is the internet's address book. It converts the easy-to-remember name of a website into the numeric address a computer needs to find it. Without DNS, you would have to type long strings of numbers to visit any website.
Is DNS the same as web hosting?
No. Hosting is the server space where your website files live. DNS only tells browsers and email systems where to find that server. You need both for a working website, but they can be provided by different companies.
Why is my website not showing after I changed DNS?
Most often it is propagation. Older copies of your DNS answer are still stored around the internet and will expire in time, usually within a few hours but sometimes up to 48. If it still isn't working after two days, double-check that the records match what your host asked for.
Can I use my domain with email but host my website elsewhere?
Yes. Your A record or CNAME decides where the website goes, while your MX records decide where email goes. They can point to completely different providers, which is why correct DNS records are so important.
Where to go from here
Now that you know how the domain name system connects your name to your website and email, you are in a better position to manage it with confidence. If you still need a domain, you can register a domain name with eStart, and if you are ready to put a site behind it, take a look at our website hosting plans. For more on getting started, read how long domain registration takes before you plan your launch.
