SOA-C02 VCE Exam Download

To manage scaling of EC2 instances in response to variable SQS message loads effectively:

Monitor SQS Queue Size: Utilize Amazon CloudWatch to monitor the number of visible messages in the SQS queue. This metric gives an indication of the workload that needs to be processed by the worker instances.

Metric Math Expression: Create a CloudWatch metric math expression that calculates the approximate number of messages visible per instance. This provides a more precise scaling metric, ensuring that each instance in the Auto Scaling group has a manageable load.

Target Tracking Scaling Policy: Implement a target tracking scaling policy based on this metric math expression. Configure the Auto Scaling group to automatically adjust its size to maintain a target value for the average number of SQS messages per instance. This approach ensures that the EC2 instances scale up during high traffic periods and scale down when the message load decreases.

This solution optimizes resource utilization and cost while maintaining performance by ensuring that the worker processes are neither overwhelmed nor idle.

Applying SCPs to an Organizational Unit:

Service Control Policies (SCPs) allow you to manage permissions for multiple AWS accounts within an organization.

Steps:

Go to the AWS Management Console.

Navigate to AWS Organizations.

Create an Organizational Unit (OU) if not already created.

Move the target accounts into the OU.

Create an SCP that denies the use of the specific EC2 instance family.

Attach the SCP to the OU.

This approach ensures that the policy is applied consistently across all accounts in the OU.

AWS Organizations SCPs

To launch EC2 instances when there are no available private IPv4 addresses in the VPC, the SysOps administrator should associate a secondary IPv4 CIDR block with the VPC and create a new subnet for the VPC.

Associate a Secondary IPv4 CIDR Block:

Open the VPC console.

Select the VPC and choose "Actions" -> "Edit CIDRs."

Add a secondary IPv4 CIDR block to increase the number of available IP addresses.

Create a New Subnet:

After adding the secondary CIDR block, create a new subnet within this CIDR block.

This new subnet will provide additional private IP addresses for launching new EC2 instances.

Associating a CIDR Block with Your VPC

Creating a Subnet

As demand on your clusters changes, you might decide to improve performance or reduce costs by changing the number of shards in your Redis (cluster mode enabled) cluster. We recommend using online horizontal scaling to do so, because it allows your cluster to continue serving requests during the scaling process.