Exam AWS Certified DevOps Engineer - Professional DOP-C02 topic 1 question 59 discussion

Option B, using two AWS Elastic Beanstalk environments to perform a blue/green deployment from the original environment to the new one, would not launch a second fleet of instances. Instead, it would create a new environment and deploy the application version to it. It also requires the use of an application version lifecycle policy to terminate the original environment in 1 hour. Option D, using AWS Elastic Beanstalk with the configuration set to Immutable and creating an .ebextension to set the deletion policy of the ALB to 1 hour, would not launch a second fleet of instances, and it would not maintain the original fleet unchanged while the second fleet is launched. Additionally, the .ebextension approach is not the recommended way to delete resources in AWS. Therefore, the correct option is C, using AWS CodeDeploy with a deployment group configured with a blue/green deployment configuration and selecting the option to Terminate the original instances in the deployment group with a waiting period of 1 hour.

Option B would require more manual intervention and configuration, making it a less optimal solution compared to the seamless blue/green deployment and automatic fleet termination provided by Option C. Option D involves unnecessary complexity around setting ALB deletion policies, and while immutable deployments offer zero-downtime updates, they don't fully meet the core requirements of automatic traffic shifting and fleet termination

Immutable strategy with Elastic Beanstalk involves deploying additional instance while Blue/Green strategy involves deploying another environment. The key difference is environment vs instances

C is ok

https://docs.aws.amazon.com/codedeploy/latest/userguide/deployment-groups-create-blue-green.html

A is correct: The question ask for a solution to automatic deployment of EC2 instances, which is the job of cloudFormation - B and D is irrelevant because it is use to deploy webapps only, not EC2 instances - C is also irrelevant because codedeploy (literlly by the name: CODEdeploy) is only used for deploying code, not EC2 instances, which is not code. Dont know why ChatGPT recommend this, but it is wrong definitely

C looks like the best solution.

To satisfy the requirements of launching a second fleet of instances with the same capacity as the original fleet, maintaining the original fleet unchanged while the second fleet is launched, transitioning traffic to the second fleet when the second fleet is fully deployed, and terminating the original fleet automatically 1 hour after the transition, the best solution is to use AWS CodeDeploy with a blue/green deployment configuration, and selecting the option to Terminate the original instances in the deployment group with a waiting period of 1 hour.

Option C