AWS Certified SysOps Administrator – Associate — Question 277

A company runs a web application that users access using the name www example com. The company manages the domain name example.com using Amazon Route 53. The company created an Amazon CloudFront distribution in front of the application and would like www.example.com to access the application through CloudFront.

What is the MOST cost-effective way to achieve this?

Answer options

• A. Create a CNAME record in Amazon Route 53 that points to the CloudFront distribution URL.
• B. Create an ALIAS record in Amazon Route 53 that points to the CioudFront distribution URL.
• C. Create an A record in Amazon Route 53 that points to the public IP address of the web application,
• D. Create a PTR record in Amazon Route 53 that points to the public IP address of the web application.

Correct answer: B

Explanation

Creating an ALIAS record in Amazon Route 53 that points to a CloudFront distribution is the most cost-effective option because Route 53 does not charge for queries to ALIAS records that target CloudFront. Conversely, querying CNAME records incurs standard Route 53 DNS query charges. Options C and D are incorrect as they bypass the CloudFront distribution entirely by routing traffic directly to the origin's public IP address.