What Is DNS?
DNS = Domain Name System
It's like a phone book for the internet. Computers use IP addresses (like 192.168.1.1), but humans use domain names (like google.com). DNS translates between them.
How DNS Works (Simplified)
- You type "example.com" in your browser
- Your computer asks DNS servers "what's the IP for example.com?"
- DNS servers look it up and reply "93.184.216.34"
- Your browser connects to that IP address
- The website loads
This happens in milliseconds, every time you visit any website.
Common DNS Record Types
| Record | Purpose | Example |
|---|---|---|
| A | Points domain to IPv4 address | 93.184.216.34 |
| AAAA | Points domain to IPv6 address | 2606:2800:220:1:: |
| CNAME | Alias to another domain | www → example.com |
| MX | Email server | mail.example.com |
| TXT | Text data (verification, SPF) | v=spf1 include:... |
What Are Nameservers?
Nameservers are the computers that store your DNS records. When you change nameservers, you're telling the internet "go ask THESE servers for my domain's DNS records."
Examples: ns1.cloudflare.com, dns1.registrar-servers.com
DNS Propagation
When you change DNS records, the changes don't happen instantly everywhere. DNS servers around the world cache (store) records for efficiency.
Propagation time: Usually 1-4 hours, can take up to 48 hours globally.
Check propagation: Use whatsmydns.net to see your DNS in different locations.
Key Takeaways
- • DNS translates domain names to IP addresses
- • A records point to your website's server
- • MX records control where email goes
- • Changes take time to propagate globally
- • Use Cloudflare or your registrar for DNS management