Q32 — AWS SOA-C02 Ch.1

Question 32 of 100 | ← Chapter 1

A company is running a website on Amazon EC2 instances behind an Application Load Balancer (ALB). The company configured an Amazon CloudFront distribution and set the ALB as the origin. The company created an Amazon Route 53 CNAME record to send all traffic through the CloudFront distribution. As an unintended side effect, mobile users are now being served the desktop version of the website. Which action should a SysOps administrator take to resolve this issue?

• A. Configure the CloudFront distribution behavior to forward the User-Agent header.
• B. Configure the CloudFront distribution origin settings. Add a User-Agent header to the list of origin custom headers.
• C. Enable IPv6 on the ALB. Update the CloudFront distribution origin settings to use the dualstack endpoint. ✓
• D. Enable IPv6 on the CloudFront distribution. Update the Route 53 record to use the dualstack endpoint.

Correct Answer: C. Enable IPv6 on the ALB. Update the CloudFront distribution origin settings to use the dualstack endpoint.

Explanation

Amazon CloudFront默认不会将某些请求头转发到源站，如User-Agent。当源服务器依赖User-Agent头来提供不同设备版本的内容时，需在CloudFront行为中显式配置转发该头部。AWS文档指出，通过转发特定头部，源站能基于这些信息动态调整响应内容。选项A正确配置了转发User-Agent头，确保源站接收并处理设备类型，而选项B错误地添加自定义头可能覆盖原始值。选项C和D涉及IPv6，与设备检测无关。