You have decided you need to change the instance type of your instances in production which are running as part of an Autoscaling Group.
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 below options can be chosen 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.
This retains the same Auto Scaling group and replaces old instances with new ones, according to the parameters specified.
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 best option for changing the instance type of instances running in an Autoscaling Group with no interruption in service and maintaining a minimum of 2 instances running is to use the AutoScalingRollingUpdate.
AutoScalingRollingUpdate allows you to update instances in an Autoscaling Group gradually, one by one, so that the service is always available. The rolling update ensures that the minimum number of instances is always running and gradually replaces old instances with new instances until all instances in the group have been updated.
AutoScalingScheduledAction allows you to schedule a change in the instance type at a specific time in the future. This could work if the service can be interrupted for a short time to make the change.
AutoScalingReplacingUpdate replaces instances in the Autoscaling Group with new instances. While this option ensures all instances are running with the latest instance type, it can result in service disruption as instances are replaced.
AutoScalingIntegrationUpdate is not an actual option provided by Amazon Web Services.
Therefore, AutoScalingRollingUpdate is the best option to change the instance type of instances in an Autoscaling Group with no interruption in service and maintaining a minimum of 2 instances running.