You’re a developer using the AWS CLI who deploys often using AWS Elastic Beanstalk and want to be
able to quickly rollback any failed deployments. Cost is not a problem and the impact should be
minimal. Which deployment policy fits your needs?
Correct answer - "immutable" : Immutable deployments perform an immutable update to launch a full
set of new instances running the new version of the application in a separate Auto Scaling
group, alongside the instances running the old version. Immutable deployments can prevent issues
caused by partially completed rolling deployments. If the new instances don't pass health
checks, Elastic Beanstalk terminates them, leaving the original instances untouched.
"all at once" - Deploy the new version to all instances simultaneously. All instances in your
environment are out of service for a short time while the deployment occurs
"rolling with additional batches" - Deploy the new version in batches, but first launch a new
batch of instances to ensure full capacity during the deployment process
"rolling" - Deploy the new version in batches. Each batch is taken out of service during the
deployment phase, reducing your environment's capacity by the number of instances in a batch