SAP-C02 Question 497
Select 4A company is running a critical web application on Amazon EC2 instances behind an Application Load Balancer (ALB) in a single AWS Region. The company wants to ensure high availability and resiliency for the application. Which combination of actions should you take to meet this requirement?
- A
Deploy the EC2 instances across multiple Availability Zones within the Region.
- B
Enable cross-zone load balancing on the Application Load Balancer.
- C
Use Amazon Route 53 with a failover routing policy to route traffic to a backup Region.
- D
Enable Auto Scaling for the EC2 instances with a minimum of one instance per Availability Zone.
- E
Launch the EC2 instances in a single Availability Zone and use Amazon S3 as a backup for static content.
Show answer and explanation
Correct answers: A, B, C, D
Explanation
To achieve high availability and resiliency for a web application, it is essential to deploy resources across multiple Availability Zones, use cross-zone load balancing to evenly distribute traffic, and enable Auto Scaling for redundancy and scalability. Additionally, implementing a failover mechanism with Amazon Route 53 ensures traffic can be routed to a backup Region during a Regional failure. Avoiding a single point of failure, such as deploying in a single Availability Zone, is critical for meeting the high availability requirement.
- A. Correct.
Deploying EC2 instances across multiple Availability Zones ensures that the application can tolerate a failure in one Availability Zone, thereby improving availability and resilience.
- B. Correct.
Enabling cross-zone load balancing ensures that traffic is distributed evenly across all Availability Zones, improving the utilization of resources and fault tolerance.
- C. Correct.
Using Amazon Route 53 with a failover routing policy allows traffic to be redirected to a backup Region in case of a Regional failure, increasing overall resiliency.
- D. Correct.
Enabling Auto Scaling ensures that instances are automatically added or removed based on demand, and setting a minimum of one instance per Availability Zone ensures redundancy across zones.
- E. Incorrect.
Launching EC2 instances in a single Availability Zone creates a single point of failure, which does not align with the goal of high availability. While using Amazon S3 for static content is a good practice, it does not address the high availability of compute resources.