SAA-C03 Question 200
Single answerA company is hosting a web application in a VPC. The application consists of multiple EC2 instances running in two Availability Zones behind an Application Load Balancer (ALB). Users have reported that certain requests to the application are taking longer than expected to respond. Upon investigation, the company discovers that specific EC2 instances are experiencing higher load than others. What should the company do to resolve this issue?
- A
Enable sticky sessions on the Application Load Balancer.
- B
Adjust the target group health check settings to use a shorter interval.
- C
Enable cross-zone load balancing on the Application Load Balancer.
- D
Increase the number of EC2 instances in the target group.
Show answer and explanation
Correct answer: C
Explanation
Cross-zone load balancing ensures that requests are evenly distributed across all registered targets, regardless of their Availability Zone. This feature helps prevent scenarios where some instances handle more traffic than others, as observed in this case. By enabling cross-zone load balancing on the ALB, the company can ensure better traffic distribution and reduce the load on individual EC2 instances.
- A. Incorrect.
Enabling sticky sessions causes requests from the same client to be sent to the same EC2 instance, which can further increase the imbalance in traffic between instances.
- B. Incorrect.
Adjusting the health check interval may help detect unhealthy instances more quickly, but it does not address traffic distribution issues between healthy instances.
- C. Correct.
Enabling cross-zone load balancing ensures that incoming traffic is evenly distributed across all EC2 instances in all Availability Zones, reducing the load imbalance.
- D. Incorrect.
Adding more EC2 instances can increase capacity, but it does not resolve the uneven distribution of traffic between existing instances.