SAP-C02 Question 254
Select 3Your company runs a critical e-commerce application on AWS, and customers rely on it for 24/7 availability. The application is hosted using an Auto Scaling group of EC2 instances behind an Application Load Balancer (ALB) across two Availability Zones (AZs). Recently, one AZ experienced an outage, leading to degraded application performance and customer complaints. How can you redesign the architecture to meet reliability requirements and ensure high availability during future AZ outages?
- A
Enable cross-zone load balancing on the Application Load Balancer.
- B
Add a third Availability Zone to the Auto Scaling group.
- C
Configure the Auto Scaling group to proactively launch instances in all enabled Availability Zones.
- D
Use Elastic Load Balancing to route traffic to a backup region during outages.
- E
Deploy an AWS Global Accelerator to distribute traffic across multiple AWS Regions.
Show answer and explanation
Correct answers: A, B, C
Explanation
To meet reliability requirements and ensure high availability during an AZ outage, the architecture must distribute traffic evenly across all enabled AZs and increase fault tolerance by utilizing additional AZs. Enabling cross-zone load balancing ensures that the load balancer spreads traffic across all instances, regardless of AZ, while adding a third AZ and ensuring proper Auto Scaling configuration enhances fault tolerance. Solutions like routing traffic to a backup region or using AWS Global Accelerator are not appropriate since the reliability issue is specific to AZs within a single Region.
- A. Correct.
Enabling cross-zone load balancing ensures that traffic is distributed evenly across all instances in the Auto Scaling group, even if one Availability Zone goes down, improving reliability.
- B. Correct.
Adding a third Availability Zone increases fault tolerance by spreading resources across more zones, reducing the impact of an AZ outage.
- C. Correct.
Configuring the Auto Scaling group to launch instances evenly across AZs ensures that all zones are utilized, and the application can handle the loss of any single AZ without performance degradation.
- D. Incorrect.
Routing traffic to a backup region is not required for this scenario since the problem is related to Availability Zones within a single Region. This solution introduces unnecessary complexity for the given requirements.
- E. Incorrect.
Deploying AWS Global Accelerator is not required as the issue pertains to reliability within a single AWS Region, not across multiple Regions.