When you first buy a domain name, it can feel like you’ve just gotten a new piece of digital real estate without a map. You have a name – myshop.com – but no idea how the internet finds the house you built on it. The pieces that make that connection are called DNS, A records and CNAMEs. Below is a step‑by‑step walk‑through of each part, without any jargon.
What a domain name really is
A domain name is the readable address people type into a browser. It replaces the long string of numbers that computers use to locate each other. Think of it like a street address for a house. The address itself doesn’t tell you where the house is built; it only tells you how to find it when you have a map.
DNS – the internet’s phone book
The Domain Name System (DNS) is that map. It stores the relationship between the readable address (myshop.com) and the actual location of the server that holds your website files. When someone types your domain into a browser, the browser asks a DNS server, “Where does myshop.com live?” The DNS server replies with the numeric location, called an IP address, and the browser goes there.
IP addresses: the numeric homes
An IP address looks like a set of four numbers separated by dots, for example, 203.0.113.45. This is the exact spot on the internet where your website lives. Servers have IP addresses, and they can change if you move your site to a new host. That’s why DNS needs a way to update the link between the domain and the server.
A records – the direct link
An “A” record (short for “address”) is the simplest DNS entry. It maps a domain name directly to an IPv4 address. In the phone‑book analogy, an A record is a line that says, “myshop.com → 203.0.113.45.” When a visitor’s browser looks up the domain, the DNS server returns that IP address, and the visitor lands on your site.
Most small‑business sites have one primary A record for the root domain (myshop.com) and possibly another for the “www” sub‑domain (www.myshop.com). Some hosts let you point both to the same IP, while others prefer separate A records for each.
CNAME records – the nickname system
A CNAME (canonical name) record works a bit like a nickname. Instead of pointing straight to an IP address, it points one domain name to another domain name. For example, you might have a CNAME that says, “blog.myshop.com → myshopblog.hostingplatform.com.”
When a browser follows a CNAME, it first resolves the alias to the target name, then looks up the A record for that target. This two‑step lookup lets you change the underlying server without touching the alias. It’s handy for services like hosted blogs, e‑commerce carts, or marketing landing pages that live on a different provider.
When to use an A record vs. a CNAME
- Use an A record when you control the server and its IP address directly. It’s the most straightforward link.
- Use a CNAME when the target is managed elsewhere, especially if the provider may change the IP behind the scenes. The alias stays stable, and you only need to update the provider’s DNS if they give you a new target name.
A common mistake is trying to point the root domain (myshop.com) to a CNAME. Most DNS providers disallow this because the root must resolve to an IP address for the internet to work correctly. Instead, you keep an A record at the root and use CNAMEs for sub‑domains.
How changes propagate – the TTL factor
Every DNS record has a TTL (time‑to‑live) value. This tells other DNS servers how long they can cache the record before checking for an update. A short TTL means changes appear quickly, but it also means more frequent lookups. A longer TTL reduces lookup traffic but can delay updates.
If you move your site to a new host, you’ll lower the TTL a day or two beforehand. That way, when the switch happens, visitors see the new IP address almost immediately. After the move, you can raise the TTL again.
Managing DNS without being a tech wizard
Most domain registrars provide a simple control panel where you can add or edit A and CNAME records. The interface typically asks for: 1. Host name – the part of the domain you’re pointing (blank for root, “www”, “blog”, etc.). 2. Record type – choose A or CNAME. 3. Value – the IP address for an A record, or the target domain for a CNAME. 4. TTL – you can usually leave the default.
If you’re using a website‑building service that handles the technical side, they will often give you the exact values to enter. You only need to copy‑paste them.
Common pitfalls to avoid
- Pointing the root to a CNAME – most DNS systems won’t allow it, and it can break your site.
- Forgetting the “www” record – many visitors type “www.myshop.com” out of habit. Make sure it points to the same place as the root, either with an A record or a CNAME that points to the root.
- Leaving old records behind – if you switch providers and forget to delete the old A or CNAME entries, traffic can be split between two servers, causing confusing behavior.
- Using IPv6 without support – an “AAAA” record is the IPv6 version of an A record. If your host doesn’t support IPv6, adding an AAAA record can cause errors.
How this fits into a leased‑website model
When you lease a site from a service, they typically set up the DNS for you. You keep your domain name, but the provider creates the necessary A and CNAME records that point to their servers. If you ever decide to move the site, you’ll need to change those records, or the provider will help you do it. Understanding the basics lets you ask the right questions and avoid surprises.
Quick checklist for a healthy DNS setup
- Root domain (myshop.com) has an A record pointing to the correct IP.
- “www” sub‑domain either points to the same IP or is a CNAME to the root.
- Any external services (blog, shop, booking) use CNAMEs that reference the provider’s domain.
- TTL is set low when you expect a change, then raised afterward.
- No stray or duplicate records remain after a migration.
Keeping these points in mind will make the technical side of your website feel less like a mystery. You’ll know where your site lives, how visitors find it, and what to do when you need to move or add new services.
For a hands‑off approach that still gives you control over your domain, consider a leasing service that handles the DNS work while you focus on your business.