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

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

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.

To reduce latency in data transfer among EC2 instances, especially in high-performance computing (HPC) applications or applications requiring low network latency, using a placement group is the best approach:

Understanding Placement Groups:

A placement group in Amazon EC2 is a logical grouping of instances within a single Availability Zone. Using placement groups, you can achieve low-latency network performance necessary for tightly coupled node-to-node communication.

Types of Placement Groups:

Cluster Placement Group: Instances are physically located close together in the same Availability Zone to provide low-latency network performance.

Partition Placement Group: Instances are divided into logical segments called partitions, reducing the likelihood of simultaneous failures.

Spread Placement Group: Instances are placed on distinct underlying hardware to reduce correlated failures.

Creating and Using a Placement Group:

You can create a placement group using the AWS Management Console, AWS CLI, or AWS SDKs.

When launching instances, specify the placement group to ensure they are launched within the same group.

aws ec2 create-placement-group --group-name my-placement-group --strategy cluster

aws ec2 run-instances --image-id ami-12345678 --count 4 --instance-type c5.large --placement GroupName=my-placement-group

Relocating Existing Instances:

Stop the instances, modify the placement group settings, and then restart them. Note that not all instance types are supported within placement groups, so check the documentation for compatibility.

Placement Groups

Cluster Instances for Low-Latency