DNS Record Types: A, CNAME, MX, and TXT Quiz Quiz

Explore the fundamental DNS record types including A, CNAME, MX, and TXT records in this concise quiz designed for beginners. Improve your understanding of how these records function and their roles in domain name resolution and email delivery.

  1. Identifying an A Record

    Which DNS record type maps a domain name directly to an IPv4 address, for example, example.com to 192.0.2.1?

    1. CNAME
    2. TXT
    3. A
    4. MX

    Explanation: The A record maps a domain name to its corresponding IPv4 address, making it essential for resolving website names to machine-readable addresses. CNAME records create aliases, not direct mappings. MX records are related to email routing and do not map domain names to IPs directly. TXT records store text information for different purposes but do not control domain-to-IP mapping.

  2. Purpose of CNAME Records

    If you want blog.example.com to point to example.com without creating a separate A record, which type should you use?

    1. TXT
    2. CNAME
    3. ANAME
    4. MX

    Explanation: CNAME records are used to create an alias from one domain or subdomain to another, allowing blog.example.com to reference example.com. MX records facilitate email delivery and cannot create domain aliases. TXT records are used for text-based data and verify domain information. ANAME is a less common and non-standard variation not widely supported.

  3. Email Routing with DNS

    Which DNS record type specifies the mail servers responsible for receiving email for a domain such as mail.example.com?

    1. A
    2. PTR
    3. MX
    4. TXT

    Explanation: MX (Mail Exchange) records define which mail servers handle emails for a domain, ensuring messages reach the right destination. TXT records contain arbitrary text data, not mail server information. A records map domains to IPs but do not define mail servers. PTR records are used in reverse DNS lookups, not for email routing.

  4. DNS Records for Verification

    If you need to add SPF or domain ownership validation information, which DNS record type allows you to do that?

    1. TXT
    2. CNAME
    3. AAAA
    4. SSHFP

    Explanation: TXT records store various types of text data, including SPF details for email validation and ownership verification codes. SSHFP records are for SSH public keys, not general-purpose verification. CNAME creates aliases but cannot store arbitrary text. AAAA records map domain names to IPv6 addresses, unrelated to verification.

  5. Selecting the Right Record Type

    What type of DNS record should you use to forward www.example.org to another name, such as host.example.org?

    1. MX
    2. SRV
    3. CNAME
    4. TXT

    Explanation: A CNAME record creates an alias from www.example.org to host.example.org, forwarding requests to the taget domain. MX records are for email servers, not web redirection. TXT records hold text information, not forwarding rules. SRV records specify services and ports, not simple name forwarding.

  6. Multiple Records for One Domain

    Which DNS record type allows you to have multiple entries for load balancing purposes, each pointing to different IPv4 addresses?

    1. MX
    2. TXT
    3. A
    4. CNAME

    Explanation: A records can be used in multiples for the same domain name, providing different IPs to distribute traffic and enable load balancing. CNAME records can only point to one domain and cannot be used in multiples for the same name. MX records can have multiple priorities but are specifically for mail servers. TXT records do not direct traffic and are not used for load balancing.

  7. TXT Record Use Cases

    Which of these is a common use for a DNS TXT record in modern web services?

    1. Storing SPF configurations
    2. Creating domain aliases
    3. Resolving domains to IPv4 addresses
    4. Defining primary mail servers

    Explanation: TXT records are often used to store SPF (Sender Policy Framework) configurations for email security and verification. Resolving domains to IPv4 addresses is the job of A records. Defining primary mail servers is done with MX records. Creating domain aliases relies on CNAME records.

  8. Mail Record Priorities

    When setting up MX records for a domain, what is the purpose of assigning a priority value to each record?

    1. To specify text strings for domain verification
    2. To create an alias for the email server domain
    3. To determine which mail server should be used first
    4. To indicate the domain's IP address

    Explanation: Priority values in MX records determine the order mail servers are contacted, with lower numbers receiving email first. MX records do not indicate the domain's IP address or hold verification text; TXT records are used for that purpose. CNAME creates aliases but does not involve priorities for mail routing.

  9. Understanding CNAME Restrictions

    Why is it not possible to have an A record and a CNAME record for the same domain name at the same time?

    1. A records and CNAME records serve the same function
    2. MX records always override CNAME records
    3. CNAME records must be the only record for their domain name
    4. DNS does not support multiple record types

    Explanation: CNAME records must be the exclusive record for their domain name according to DNS standards, which ensures there is only one canonical mapping. A records and CNAME records serve different purposes, not the same function. DNS allows multiple record types overall, but not CNAME plus others for the same name. MX records do not override CNAME records.

  10. IPv4 Address Assignment

    If you want users to reach your website using IPv4, which DNS record type must be configured?

    1. A
    2. MX
    3. AAAA
    4. TXT

    Explanation: A records are specifically used to assign IPv4 addresses to domain names, enabling users to reach websites via IPv4. MX records manage email delivery, not web access. TXT records hold text information or verification, unrelated to IP addressing. AAAA records are for IPv6 addresses, not IPv4 connectivity.