AWS DevOps Engineer Professional Practice Test

What method would you use to gracefully drain connections to EC2 instances before updates during a CodeDeploy deployment?

1. Use an AWS Lambda function

2. Write a script during the BeforeBlockTraffic lifecycle hook

3. Set up a load balancer

4. Apply an Auto Scaling policy

The correct answer is: Write a script during the BeforeBlockTraffic lifecycle hook

The chosen method to gracefully drain connections to EC2 instances before updates during a CodeDeploy deployment involves utilizing a script during the BeforeBlockTraffic lifecycle hook. This approach is effective because it allows you to implement custom logic that can ensure ongoing connections are properly handled before the instance is taken out of service. During the BeforeBlockTraffic lifecycle hook, the script can be used to notify any connected clients that traffic will soon be blocked, allowing them to either complete their current requests or cleanly disconnect. This step is essential for maintaining application stability and data integrity, especially if the application is stateful. By gracefully draining connections, you minimize the risk of interrupted service for users. While using an AWS Lambda function could theoretically accomplish some tasks related to traffic management, it does not specifically cater to the needs of draining connections before blocking traffic in the context of a CodeDeploy deployment. Setting up a load balancer is an excellent practice for distributing traffic among multiple instances, but on its own does not inherently manage connection draining in relation to CodeDeploy lifecycle hooks. Load balancers can help in the broader architecture, but the specific need to drain connections before updates is best handled via lifecycle hooks. Applying an Auto Scaling policy primarily focuses on adjusting the number of instances in response to demand;