SOA-C02 Question 90
Select 2Your company hosts a web application on Amazon EC2 instances in a single Availability Zone. These instances store shared configuration files that are frequently updated by the application. Recently, the application experienced downtime when the Availability Zone encountered an outage. You have been tasked with redesigning the architecture to make it fault-tolerant while ensuring that the shared configuration files remain accessible across multiple Availability Zones. Which combination of actions will achieve this?
- A
Move the shared configuration files to Amazon Elastic File System (Amazon EFS) and enable multi-AZ replication.
- B
Allocate an Elastic IP address to each EC2 instance for stable connectivity.
- C
Distribute the EC2 instances across multiple Availability Zones.
- D
Use an Amazon S3 bucket to store the shared configuration files.
- E
Enable Amazon EFS lifecycle management to optimize storage costs.
Show answer and explanation
Correct answers: A, C
Explanation
To achieve fault tolerance, you need to address both the application servers and the shared configuration files. By distributing EC2 instances across multiple Availability Zones, you ensure that the application remains available even if one Availability Zone fails. Amazon EFS with multi-AZ replication ensures that the shared configuration files are accessible across all Availability Zones, making it the most suitable storage solution for this scenario.
- A. Correct.
Moving the shared configuration files to Amazon EFS with multi-AZ replication ensures that the files are accessible across multiple Availability Zones, providing fault tolerance for the data.
- B. Incorrect.
Allocating an Elastic IP address only provides a static IP address for an instance, which does not contribute to fault tolerance or availability across multiple Availability Zones.
- C. Correct.
Distributing EC2 instances across multiple Availability Zones ensures that the application remains available even if one Availability Zone fails, increasing fault tolerance.
- D. Incorrect.
While Amazon S3 could store the configuration files, it is not ideal for scenarios requiring shared file system access with frequent updates. Amazon EFS is a better solution for this use case.
- E. Incorrect.
Enabling Amazon EFS lifecycle management helps with cost optimization but does not directly contribute to making the workload fault-tolerant.