A, AAAA, and CNAME records

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 These are DNS (Domain Name System) record types that help route internet traffic to the right places. Each one serves a different purpose in how domains and subdomains are resolved to IP addresses or other domain names.

Here’s a quick breakdown of what A, AAAA, and CNAME records are:

📌 1. A Record (Address Record)

  • What it does: Maps a domain name to an IPv4 address (e.g., 192.168.1.1).

  • Use case: It tells DNS that "when someone goes to example.com, send them to the server at IP address 192.168.1.1".

Example:

example.com.   IN   A   93.184.216.34

So if a user types example.com, the browser knows to connect to 93.184.216.34.

📌 2. AAAA Record (IPv6 Address Record)

  • What it does: Maps a domain name to an IPv6 address (e.g., 2606:2800:220:1:248:1893:25c8:1946).

  • Use case: Similar to an A record, but for modern IPv6 addresses.

Example:

text

example.com.   IN   AAAA   2606:2800:220:1:248:1893:25c8:1946

This allows devices using IPv6 to connect directly to the server.

📌 3. CNAME Record (Canonical Name Record)

  • What it does: Creates an alias from one domain to another domain (not to an IP).

  • Use case: Useful when you want multiple domain names to point to the same server or resource.

Example:

www.example.com.   IN   CNAME   example.com.

This means www.example.com is just an alias for example.com and will use the same A or AAAA record of example.com.

🔄 Summary Table

Record TypeMaps ToIP VersionCommon Use Case
AIPv4 addressIPv4example.com → 93.184.216.34
AAAAIPv6 addressIPv6example.com → 2606:...
CNAMEAnother domainN/Ablog.example.com → example.com

❗ Notes:

  • A domain with a CNAME record cannot have any other records (like A or MX) at the same level.

  • Use A or AAAA for pointing to IP addresses, and CNAME when you want to redirect to another domain.

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