What is the function of an MX Record?

What is the function of an MX Record?

• A. It specifies which mail servers are responsible for receiving email for the domain.
• B. It maps domain names to IP addresses for websites.
• C. It identifies the authoritative DNS server for the domain.
• D. It enables DNSSEC for the domain.

Answer: (A)

An MX record tells the world which mail servers handle email for a domain. It stores the hostname of the mail server and a priority, so when someone sends email to user@domain, the sending mail transfer agent looks up the MX records for the domain and tries to deliver to the highest-priority server first, falling back to others if needed. The target host must itself have an A or AAAA record to resolve to an IP address. This isn’t about mapping domain names to IPs for websites (that’s A/AAAA), identifying the domain’s authoritative DNS servers (that’s NS), or enabling DNSSEC (which uses DNSKEY/DS records).

An MX record tells the world which mail servers handle email for a domain. It stores the hostname of the mail server and a priority, so when someone sends email to user@domain, the sending mail transfer agent looks up the MX records for the domain and tries to deliver to the highest-priority server first, falling back to others if needed. The target host must itself have an A or AAAA record to resolve to an IP address.

This isn’t about mapping domain names to IPs for websites (that’s A/AAAA), identifying the domain’s authoritative DNS servers (that’s NS), or enabling DNSSEC (which uses DNSKEY/DS records).