Networking Essentials easy
What specifically does a DNS 'A Record' resolve?
- A It resolves a canonical domain name to a specialized 128-bit IPv6 address to support the next generation of internet-connected IoT devices.
- B It resolves a human-readable domain name (e.g., example.com) to a specific 32-bit IPv4 address (e.g., 192.0.2.1) for machine-level routing.
- C It maps an incoming email address to the prioritized list of Mail Exchange (MX) servers responsible for receiving messages for a specific domain.
- D It creates a symbolic alias that redirects one domain name to another canonical name, allowing multiple services to share a single physical server.
Answer: B. It resolves a human-readable domain name (e.g., example.com) to a specific 32-bit IPv4 address (e.g., 192.0.2.1) for machine-level routing.
The 'A' in A-record stands for 'Address'. It is the most fundamental DNS record type, mapping a domain name directly to an IPv4 address. In contrast, 'AAAA' records are used for IPv6 addresses, 'CNAME' records create aliases between domain names, and 'MX' records are specifically for routing email traffic to the correct mail server. Choosing an A-record provides the most direct resolution path, though modern systems often use CNAMEs for better flexibility when pointing to load balancers or CDNs.
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