Which AWS DNS service is used to map domain names to IP addresses, CloudFront distributions, and other targets?

Explanation

Amazon Route 53 is the AWS DNS service. It is used to map custom domains to targets such as CloudFront and ALB.

Per-choice explanations

Practical Use

Amazon Route 53 is the authoritative DNS service provided by AWS. By acquiring and managing custom domains and registering DNS records (A, AAAA, CNAME, MX, TXT, and others) for those domains, it provides name resolution from domain names to AWS resources (CloudFront distributions, Application Load Balancer, Amazon S3 static sites, Amazon EC2, and so on). For AWS resources, there is a Route 53–specific mechanism called an Alias record, which lets you register the DNS name of a CloudFront distribution or ALB as an Alias instead of a CNAME. Alias records are free to use and can also be set on the zone apex (example.com itself), which differs from CNAMEs. On the exam, Route 53 is the expected answer for the prompt asking which AWS service provides DNS name resolution. Common distractors include services unrelated to DNS, such as Amazon EBS (block storage), AWS Lambda (serverless compute), and Amazon DynamoDB (NoSQL database). Once the keywords "DNS," "domain name," and "name resolution" appear together, the other choices can be eliminated. In practice, the key point in selection is the routing policies of Route 53. Simple routing, weighted routing (A/B testing and gradual releases), latency-based routing (directing users to the closest Region), geolocation routing (branching destinations by country or region), failover routing (switchover based on health checks), and multivalue answer routing are available, and you choose among them based on workload requirements. CLF-C02 frequently asks about the basic equation "Route 53 equals DNS," along with the fact that it also provides domain registration and health check functions.