You have decided that you need to change the instance type of your production instances which are running as part of an AutoScaling group.
The entire architecture is deployed using CloudFormation Template.
You currently have 4 instances in Production.
You cannot have any interruption in service and need to ensure 2 instances are always running during the update.
Which of the options below listed can be used for this?
Click on the arrows to vote for the correct answer
A. B. C. D.Answer - A.
The AWS::AutoScaling::AutoScalingGroup resource supports an UpdatePolicy attribute.
This is used to define how an Auto Scaling group resource is updated when an update to the CloudFormation stack occurs.
A common approach to updating an Auto Scaling group is to perform a rolling update, which is done by specifying the AutoScalingRollingUpdate policy.
According to the parameters specified, this retains the same Auto Scaling group and replaces old instances with new ones.
For more information on Autoscaling updates, please refer to the below link:
https://aws.amazon.com/premiumsupport/knowledge-center/auto-scaling-group-rolling-updates/The option that can be used for updating the instance type of instances in an AutoScaling group without any interruption in service and ensuring 2 instances are always running during the update is AutoScalingReplacingUpdate.
AutoScalingReplacingUpdate is a type of update policy that replaces instances in the AutoScaling group. This policy replaces instances in batches to ensure that the minimum number of instances is always running. It allows you to specify the minimum number of instances to keep running during the update, and the maximum number of instances that can be updated in a single batch.
AutoScalingRollingUpdate updates the instances in a rolling fashion, but this policy cannot guarantee that a minimum number of instances are always running during the update.
AutoScalingScheduledAction is used to schedule a scaling action, and it does not guarantee that a minimum number of instances are always running during the update.
AutoScalingIntegrationUpdate is not a valid update policy.
Therefore, the correct answer is C. AutoScalingReplacingUpdate.