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Exam Question Walkthrough: AWS Certified Solutions Architect - Associate (SAA-C03)
Explore a sample question from the SAA-C03 exam on AWS storage options. Understand the best choice for low latency and high availability.
Running a mission-critical application on AWS can lead to tricky decisions. Candidates often stumble on storage options when balancing low latency and high availability. Let’s clarify this with a specific exam question.
The question
A company is running a mission-critical application on AWS that requires low-latency access to its data. The data is accessed by multiple EC2 instances across different Availability Zones. What is the best storage option to ensure low latency and high availability?
- A. Amazon S3
- B. Amazon EFS
- C. Amazon FSx for Lustre
- D. Amazon DynamoDB
Think before you scroll
Before selecting an option, consider how each storage solution handles latency and availability. The question emphasizes low-latency access from multiple instances across different Availability Zones. Weigh the characteristics of each option.
The answer
The correct option is B. Amazon EFS. Amazon Elastic File System (EFS) provides the necessary file storage that can be accessed with low latency from multiple EC2 instances across different Availability Zones, ensuring high availability.
Why the other options lose
- A. Amazon S3: While S3 provides high durability, it is not optimized for low-latency access, making it less suitable for applications requiring frequent data retrieval.
- C. Amazon FSx for Lustre: This option is designed for high performance, particularly for compute-intensive workloads. However, it may not match EFS when it comes to availability across multiple Availability Zones.
- D. Amazon DynamoDB: This is a NoSQL database ideal for key-value access patterns. It does not meet the file storage needs specified in the question, making it an unsuitable choice.
The concept behind it
The key principle here is understanding the characteristics of storage solutions in AWS. For applications requiring low-latency access and high availability, EFS is designed to support concurrent access from multiple instances across different zones, making it a perfect fit. Knowing the specific use cases for each storage option helps in selecting the right one.
Exam trap to remember
Remember the two-question rule: if low latency and multiple instance access are in play, EFS is often the right choice. Always consider the unique requirements of your application.