DNS explained — the phone book of the internet
DNS (Domain Name System) is the system that translates domain names such as "your-company.dk" into the IP addresses that computers use to find each other on the internet. Think of it as the phone book of the internet — you look up a name and get a number.
What happens when someone visits your website?
When a customer types your-company.dk in the browser, the computer asks a DNS server: "Which IP address belongs to this domain?" The DNS server replies e.g. "185.60.40.12" — and the browser connects to that server. The whole thing typically takes less than 50 milliseconds, and you don't notice it.
A record — points your domain to a server
An A record is the most basic DNS entry. It says: "your-company.dk should point to IP address 185.60.40.12." When you get new web hosting or change server, the A record is what needs updating.
MX record — controls where your email is delivered
MX (Mail Exchange) tells the world's mail servers: "Email to @your-company.dk should be delivered to this mail server." If you switch from one email system to another, the MX record is the most important thing to get right — otherwise your email stops working.
CNAME — an alias for another domain
A CNAME record is an alias: "www.your-company.dk is the same as your-company.dk." It is also used to point subdomains (e.g. shop.your-company.dk) to specific services.
TXT record — text information for verification
TXT records are used to store text information about your domain. The most common are SPF records (email security), DKIM keys and domain verification (e.g. when Google or Microsoft need to confirm that you own the domain).
Propagation — why do DNS changes take time?
When you change a DNS record, it can take up to 24-48 hours before the change is visible everywhere in the world. This is because DNS servers around the world cache (store) the old information for a period. In practice, the update often happens within 1-4 hours.
We manage DNS for all our customers, so you don't have to worry about records and settings yourself. Need a change? Contact us and we will take care of it — typically the same day.
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