In DNS, what is a CNAME record used for?

• A. Hosting email services
• B. Creating an alias from one domain name to another
• C. Validating domain ownership
• D. Pointing a domain to an IP address

Answer: (B)

A CNAME record creates an alias by mapping one domain name to another domain name, rather than to an IP address. When a resolver looks up the alias, it follows the target canonical name and then uses that target’s A or AAAA records to obtain the actual IP. This is useful when you want multiple names to point to the same service without updating IPs everywhere—for example, making www.example.com resolve to example.net or directing a subdomain to a third-party host while keeping the canonical name stable. Because it points to another domain name, not a direct address, a CNAME isn’t used to host email (that’s handled with MX records) and isn’t the method for validating ownership (typically TXT records). An address is reached with A or AAAA records, not a CNAME.