Networking & HTTP·Networking from DNS to production

IP addresses and DNS

Read IPv4 and IPv6, follow DNS records and understand TTL caching.

Beginner 13 min read Lesson 2 of 300 Challenge included

What you will be able to do

Use A and AAAA for host addresses.
Use CNAME for aliases.
Lower TTL before a planned migration.
Use dig to inspect records and propagation.

In plain English

An IP address identifies an interface. DNS maps names to records: A for IPv4, AAAA for IPv6, CNAME for aliases, MX for mail and TXT for verification. TTL controls how long resolvers may cache an answer.

terminalTerminal

dig +short A example.com
dig +short AAAA example.com
dig +short MX example.com

Your turn

Look up an A record

Easy

Write a dig command that returns only the IPv4 addresses for example.com.

BASH · starter

dig example.com

Check your understanding before moving on.

Knowledge checkQuestion 1

Which record maps a name to an IPv4 address?

Select an answer to continue

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Next: TCP and UDP

Lesson 2 of 300 · 0% of course