SOA-C02 Question 77
Select 3Your organization has a critical web application running on Amazon EC2 instances in a single Availability Zone. To improve high availability and resilience, you need to redesign the architecture. Which of the following steps should you take to achieve this goal?
- A
Deploy the EC2 instances across multiple Availability Zones.
- B
Place an Application Load Balancer in front of the EC2 instances.
- C
Enable Auto Scaling to handle traffic spikes and failures.
- D
Store the application code on an Amazon EBS volume attached to one EC2 instance.
- E
Use Elastic IPs to ensure the application is accessible even if an instance fails.
Show answer and explanation
Correct answers: A, B, C
Explanation
To implement a high availability and resilient environment, the application should be deployed across multiple Availability Zones to prevent a single point of failure. An Application Load Balancer ensures traffic is routed to healthy instances, and Auto Scaling ensures the environment can adapt to changing workloads and recover from failures. These steps collectively enhance the application's resilience and availability.
- A. Correct.
Deploying EC2 instances across multiple Availability Zones increases fault tolerance by ensuring that the application remains available even if one Availability Zone becomes unavailable.
- B. Correct.
Using an Application Load Balancer distributes traffic across healthy EC2 instances in multiple Availability Zones, further enhancing availability and resilience.
- C. Correct.
Enabling Auto Scaling allows the environment to automatically adjust the number of instances based on demand and replace unhealthy instances, improving both availability and resilience.
- D. Incorrect.
Storing the application code on an EBS volume attached to a single instance introduces a single point of failure because EBS volumes are specific to a single Availability Zone.
- E. Incorrect.
Elastic IPs provide static IP addresses but do not inherently improve availability or resilience. They are useful for maintaining consistent connections but do not address fault tolerance or high availability.