SOA-C02 Exam Dumps : AWS Certified SysOps Administrator - Associate (SOA-C02)

# Enable instance scale-in protection for specific instance.

aws autoscaling set-instance-protection --instance-ids i-5f2e8a0d --auto-scaling-group-name my-asg --protected-from-scale-in

# Disable instance scale-in protection for the specified instance.

aws autoscaling set-instance-protection --instance-ids i-5f2e8a0d --auto-scaling-group-name my-asg --no-protected-from-scale-in

To ensure that EC2 instances in an Auto Scaling group are not interrupted during message processing, the most effective method is to implement scale-in protection for the instances while they are actively processing messages. This can be done programmatically by modifying the Auto Scaling group's settings using the Amazon EC2 Auto Scaling API.

Starting Message Processing: When an instance begins processing a message, your application should make an API call to enable scale-in protection. This is done using the SetInstanceProtection action, setting the ProtectedFromScaleIn parameter to true for that specific instance.

Completing Message Processing: Once the message has been processed, another API call should be made to disable scale-in protection. This is done by calling the SetInstanceProtection action again, but this time setting the ProtectedFromScaleIn parameter to false.

This method ensures that while messages are being processed, the instances are not terminated by the Auto Scaling group regardless of any scale-in activities that might be triggered by other parameters like CPU utilization or a decrease in the number of messages in the queue.

AWS Documentation Reference:

You can refer to the AWS documentation on managing instance scale-in protection in Auto Scaling groups for more details: Instance Scale-In Protection.

The MixedInstancesPolicy feature in Auto Scaling groups allows for the configuration of both On-Demand and Spot Instances within a single Auto Scaling group, balancing cost savings and high availability:

MixedInstancesPolicy: Enables configuration to maintain a minimum of three On-Demand Instances and add Spot Instances when prices drop, without the need to create separate launch templates.

Setting Maximum Spot Price: Ensures that additional Spot Instances are launched only when within the defined budget.

This solution offers the least management overhead, as it combines both On-Demand and Spot instances seamlessly in one configuration.

Here are the steps to update an existing AWS CloudFormation stack:

Log in to the AWS Management Console and navigate to the CloudFormation service in the us-east-2 Region.

Find the existing stack named 1700182 and click on it.

Click on the "Update" button.

Choose "Replace current template" and upload the updated CloudFormation template from the Amazon S3 bucket named "cloudformation-bucket"

In the "Parameter" section, update the EC2 instance type to us-east-t2.nano and add the IP address range 192.168.100.0/30 for SSH access.

Replace the instance profile IAM role with IamRoleB.

In the "Capabilities" section, check the checkbox for "IAM Resources"

Choose the role CFServiceR01e and click on "Update Stack"

Wait for the stack to be updated.

Once the update is complete, navigate to the stack and click on the "Stack options" button, and select "Prevent updates to prevent accidental deletion"

To get the value of the Prodlnstanceld , navigate to the "Outputs" tab in the CloudFormation stack and find the key "Prodlnstanceld". The value corresponding to it is the value that you need to enter in the text box below.

Note:

You can use AWS CloudFormation to update an existing stack.

You can use the AWS CloudFormation service role to deploy updates.

You can refer to the AWS CloudFormation documentation for more information on how to update and manage stacks: