AWS Certified Advanced Networking – Specialty (ANS-C00) — Question 255

You have a server that serves www, FTP, and mail. You need to access this server using www.yourname.com, ftp.yourname.com, and mail.yourname.com. You want to ensure an IP change results in the least number of other changes.
What is the best solution?

Answer options

• A. Create PTR records and point the IP address of the server back to www, ftp, and mail.
• B. Create an A record pointing to the server's IP address and create CNAME records for www, ftp, and mail and point those to the A record.
• C. Create an A record for www, ftp and mail, and point it to the ALIAS of the server.
• D. Create CNAME records for www, ftp, and mail and point those to the A record already provided to the instance by AWS.

Correct answer: B

Explanation

The correct answer is B because creating an A record for the server's IP and using CNAME records for the subdomains allows for easy updates in case of an IP change. Options A and C do not provide a flexible solution for IP changes, while option D may not be the best practice as it relies on the existing A record without a direct reference to the server's IP.