AWS Certified Solutions Architect – Professional — Question 362

You are setting up some EBS volumes for a customer who has requested a setup which includes a RAID (redundant array of inexpensive disks). AWS has some recommendations for RAID setups.
Which RAID setup is not recommended for Amazon EBS?

Answer options

• A. RAID 1 only
• B. RAID 5 only
• C. RAID 5 and RAID 6
• D. RAID 0 only

Correct answer: C

Explanation

AWS recommends against using RAID 5 and RAID 6 configurations for Amazon EBS because the parity write operations consume a large portion of the IOPS available to the volumes. Since EBS volumes are already replication-backed for durability, the additional redundancy of RAID 5 and 6 introduces a significant performance penalty without much benefit. Instead, RAID 0 is recommended for performance maximization and RAID 1 for mirroring.