Question 1

What is a DNS record?

Accepted Answer

DNS (Domain Name System) records map domain names to corresponding values. Common types include: A records pointing to IPv4 addresses, AAAA records to IPv6, CNAME records to other domains, MX records specifying mail servers, NS records for authoritative DNS servers, TXT records for text info (e.g., SPF, DKIM), and SOA records for domain management info.

Question 2

What is the difference between A and CNAME records?

Accepted Answer

An A record maps a domain directly to an IP address (e.g., 93.184.216.34), while a CNAME record maps a domain to another domain (an alias). CNAME adds an extra DNS lookup but is more flexible. Note: CNAME records cannot coexist with other record types on the same subdomain, and root domains (e.g., example.com) typically cannot use CNAME.

Question 3

What does MX record priority mean?

Accepted Answer

MX records have a priority value (lower number = higher priority). When sending mail, the mail server will try the highest-priority MX server first. If that connection fails, it tries lower-priority servers. This provides redundant mail server backup. E.g., "10 mail1.example.com" and "20 mail2.example.com" — mail is sent to mail1 first.

Question 4

What are TXT records used for?

Accepted Answer

TXT records are most commonly used for domain verification and security configuration. Main uses: SPF (Sender Policy Framework) prevents email forgery, DKIM (DomainKeys Identified Mail) digitally signs emails, DMARC (Domain-based Message Authentication) manages email authentication policies. Many services (like Google, Cloudflare) also use TXT records to verify domain ownership.

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