You have written an AWS Serverless Application Model (AWS SAM) template to create a Lambda function. As AWS SAM service has integrated with AWS CodeDeploy to ensure safe Lambda deployments, you prefer to shift users to the new version gradually. A piece of template is as below:

Answer options:

A.If an alarm such as AliasErrorMetricAlarm appears, CodeDeploy does not roll back the deployment.
B.10 percent of the traffic is shifted to the new version all at once. Then the remaining 90 percent of traffic is shifted to the new version 5 minutes later.
C.If PreTrafficLambdaForValidation has failed, the deployment is not rolled back.
D.If PostTrafficLambdaForValidation has failed, the deployment is not rolled back.

Correct Answer – B
If SAM is used to deploy serverless application, it has integrated with CodeDeploy service to ensure safe deployment. CodeDeploy has supported three types of deployment for Lambda function which are Canary, Linear and All-at-once. For the deployment configuration details of CodeDeploy on Lambda Compute Platform, refer to
ttps://docs.aws.amazon.com/codedeploy/latest/userguide/deployment-configurations.html
Option A is incorrect: Because as long as a preconfigured CloudWatch alarm is triggered, CodeDeploy rolls back the deployment.
Option B is CORRECT: Because Canary10Percent5Minutes belongs to Canary deployment. It means that 10 percent of the whole traffic is shifted to the new software release at once. Then all the other traffic is shifted after 5 minutes.
Option C is incorrect: Because for CodeDeploy service, the pre-hook and post-hook tests validate the sanity of the deployment status. If anything goes wrong with the hooks, the deployment will be rolled back. This is also a method to prevent further damage on the application from a problematic deployment.
Option D is incorrect: Same reason as Option
C.