SOA-C02 AWS Certified SysOps Administrator - Associate (SOA-C02) Questions and Answers

To optimize the cost of a workload running in multiple AWS Regions using AWS Lambda and EC2 On-Demand Instances, the SysOps administrator should purchase Compute Savings Plans based on the usage during the past 30 days.

Compute Savings Plans:

Compute Savings Plans provide the most flexibility and can be applied across various compute services such as EC2, AWS Lambda, and Fargate.

They offer significant savings compared to On-Demand pricing.

Analysis and Purchase:

Analyze the compute usage over the past 30 days to determine the baseline usage.

Purchase Compute Savings Plans based on this baseline to maximize savings while maintaining flexibility across different regions and compute services.

Step-by-Step Explanation:

Understand the Problem:

Minimize potential data loss and recovery time for a MySQL database running on an Amazon EC2 instance.

Analyze the Requirements:

Reduce the risk of data loss.

Ensure quick recovery in the event of a database failure.

Aim for operational efficiency.

Evaluate the Options:

Option A: Create a CloudWatch alarm to invoke a Lambda function that stops and starts the EC2 instance.

This addresses system failures but does not help with minimizing data loss or ensuring database redundancy.

Option B: Create an Amazon RDS for MySQL Multi-AZ DB instance and use a MySQL native backup stored in Amazon S3.

RDS Multi-AZ deployments provide high availability and durability by automatically replicating data to a standby instance in a different Availability Zone.

Using a MySQL native backup stored in Amazon S3 ensures data can be restored efficiently.

Option C: Create an RDS for MySQL Single-AZ DB instance with a read replica.

This provides read scalability but does not ensure high availability or failover capabilities.

Option D: Use Amazon DLM to take hourly snapshots of the EBS volume.

This helps with backups but does not provide immediate failover capabilities or minimize downtime effectively.

Select the Best Solution:

Option B: Using Amazon RDS for MySQL Multi-AZ ensures high availability and automated backups, significantly minimizing data loss and recovery time.

Amazon RDS Multi-AZ Deployments

Backing Up and Restoring an Amazon RDS DB Instance

Using Amazon RDS for MySQL Multi-AZ provides a highly available and durable solution with automated backups, ensuring minimal data loss and quick recovery.

To securely allow a security administrator to review the VPC configuration of developer AWS accounts, the best approach is to create a cross-account IAM role with read-only access to VPC resources. Here’s how to do it:

Create IAM Policy:

In each developer account, create an IAM policy with read-only permissions "Version": "2012-10-17",

"Statement": [

{

"Effect": "Allow",

"Action": [

"ec2:DescribeVpcs",

"ec2:DescribeSubnets",

"ec2:DescribeRouteTables",

"ec2:DescribeSecurityGroups",

"ec2:DescribeNetworkAcls"

],

"Resource": "*"

}

]

}

Create Cross-Account IAM Role:

Create an IAM role in each developer account, assign the read-only policy to the role, and allow the security administrator's account to assume the role.

{

"Version": "2012-10-17",

"Statement": [

{

"Effect": "Allow",

"Principal": {

"AWS": "arn:aws:iam::security-admin-account-id:root"

},

"Action": "sts:AssumeRole"

}

]

}

Assume the Role:

The security administrator can assume the role from their own account using the AWS Management Console or AWS CLI.

aws sts assume-role --role-arn arn:aws:iam::developer-account-id:role/role-name --role-session-name security-admin-session

Review VPC Configuration:

After assuming the role, the security administrator can review the VPC configuration using the AWS Management Console or AWS CLI with the temporary credentials.

IAM Policies and Roles

Cross-Account Access

AWS CLI Assume Role

To remediate the InsufficientInstanceCapacity error when scaling the Auto Scaling group, the SysOps administrator can take the following actions:

Change the Instance Type:

Insufficient capacity errors can occur if there is not enough available capacity for the specified instance type in the selected Availability Zone.

Changing to a different instance type might resolve the capacity issue.

https://docs.aws.amazon.com/vpc/latest/userguide/vpc-network-acls.html

To block traffic to the external IP address identified by Amazon GuardDuty, the SysOps administrator should create a network ACL and add an outbound deny rule for traffic to the external IP address.

Network ACL:

Network ACLs (Access Control Lists) are stateless and operate at the subnet level. They can allow or deny specific inbound and outbound traffic based on rules.

Steps to Implement:

Go to the VPC console and select the network ACL associated with the subnet containing the EC2 instance.

Add an outbound rule to deny traffic to the external IP address provided by GuardDuty.

Ensure the rule is properly placed in the rule number order to be evaluated correctly.

Network ACLs

GuardDuty Documentation

The reason is that it uses the Amazon CloudWatch billing alarm which is a built-in service specifically designed to monitor and alert on cost usage of your AWS account, which makes it a more suitable solution for this use case. The alarm can be configured to detect when costs reach 75% of the threshold and when it is triggered, it can publish a message to an Amazon Simple Notification Service (Amazon SNS) topic. The email distribution list can be subscribed to the topic, so that they will receive the alerts when costs reach 75% of the threshold.

AWS Budgets allows you to track and manage your costs, but it doesn't specifically focus on data transfer costs between regions, and it might not provide as much granularity as CloudWatch Alarms.

The best combination of steps to meet this requirement is to sign in to the new account by using root user credentials and change the support plan, and to create an IAM user that has administrator privileges in the new account.

Signing in to the new account by using root user credentials will allow the SysOps administrator to access the account and change the support plan to AWS Business Support. Additionally, creating an IAM user that has administrator privileges in the new account will ensure that the SysOps administrator has the necessary access to manage the account and make changes to the support plan if necessary.

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 meet the requirement of consistent performance of 10,000 IOPS with the least cost, the SysOps administrator should use a General Purpose SSD (gp3) Amazon EBS volume:

General Purpose SSD (gp3) EBS Volume:

The gp3 volume type can be provisioned with the required IOPS without the need for additional capacity, making it a cost-effective solution compared to Provisioned IOPS SSD (io1) volumes.

Network ACLs (Access Control Lists) are stateless, meaning that return traffic must be explicitly allowed. While the inbound rule allows HTTP traffic on port 80, the absence of an outbound rule permitting return traffic on ephemeral ports (typically 1024-65535) prevents the response from reaching the client.

To resolve this:

Add an Outbound Rule:

Protocol: TCP

Port Range: 1024-65535

Destination: 0.0.0.0/0

Action: Allow

This configuration ensures that the server can send responses back to clients initiating HTTP requests.

AWS Config is the best service to automatically manage and remediate S3 bucket permissions that violate corporate policies against public access. AWS Config continuously monitors and records AWS resource configurations and allows you to create rules that trigger automatic responses when public access configurations are detected. This approach is highly operationally efficient as it automates compliance and enforcement of security policies without manual intervention. Option A is correct. AWS Config can be used to assess, audit, and evaluate the configurations of AWS resources, including S3 buckets. Reference AWS Config.

DependsOn Attribute in CloudFormation:

The DependsOn attribute in AWS CloudFormation ensures that one resource is created only after another resource has been successfully created. In this case, it ensures that the EC2 instance is fully launched before the custom resource (the Lambda function) is executed.

Steps:

Update the CloudFormation template to include the DependsOn attribute for the custom resource.

Ensure that the custom resource references the EC2 instance.

Resources:

MyEC2Instance:

Type: AWS::EC2::Instance

Properties:

# EC2 properties

MyCustomResource:

Type: Custom::MyCustomResource

DependsOn: MyEC2Instance

Properties:

ServiceToken: !GetAtt MyLambdaFunction.Arn

# Other properties

AWS CloudFormation DependsOn Attribute

AWS Global Accelerator:

AWS Global Accelerator is a service that improves the availability and performance of your applications with a global user base. It provides static IP addresses that act as a fixed entry point to your application endpoints (such as ALBs).

Steps:

Go to the AWS Management Console.

Navigate to Global Accelerator.

Click on "Create accelerator."

Configure the accelerator by providing a name and adding listeners.

Add your Application Load Balancer as an endpoint.

Allocate two static IP addresses.

This setup ensures that your application is accessible via two static IP addresses, fulfilling the requirement.

AWS Global Accelerator

To ensure that all traffic, including rejected traffic, is logged in VPC Flow Logs, you need to create a new flow log with a filter setting to capture all traffic.

Create a New Flow Log:

Open the VPC console.

Select the VPC for which you want to create the flow log.

Choose "Create flow log."

In the filter setting, select "All" to capture all traffic (accepted and rejected).

Flow Log Configuration:

Ensure that the destination for the flow logs (e.g., CloudWatch Logs or S3) is properly configured.

Specify the appropriate IAM role to allow VPC Flow Logs to publish logs to the destination.

VPC Flow Logs

Creating a Flow Log

If AWS Lambda function logs are not appearing in Amazon CloudWatch, it is typically due to insufficient permissions:

IAM Role Permissions: The execution role assigned to the Lambda function must have the necessary permissions to interact with CloudWatch Logs. This includes actions like logs:CreateLogGroup, logs:CreateLogStream, and logs:PutLogEvents.

Check and Update Role: Verify that the IAM role used by the Lambda function includes a policy granting these permissions. If not, update the role to include these permissions.

Log Group and Stream: With the appropriate permissions, the Lambda function will be able to create or use a log group and stream in CloudWatch Logs and publish log messages accordingly.

Ensuring the Lambda function has the correct permissions is essential for diagnostics and monitoring, allowing log data to be captured and reviewed in CloudWatch Logs.

 Create an SNS Topic and Subscription:

Amazon SNS allows you to send notifications to multiple endpoints.

Steps:

Go to the AWS Management Console.

Navigate to SNS and create a new topic.

Create a subscription for the topic using the email protocol.

Enter the architecture team's email address as the subscriber.

Amazon SNS

 Create an EventBridge Rule:

Amazon EventBridge can monitor events and trigger actions.

Steps:

Go to the AWS Management Console.

Navigate to EventBridge.

Create a new rule that reacts to EC2 instance launch events.

Specify the SNS topic as the rule's target.

Objective:

Address high and unpredictable CPU usage by automating the scaling of resources.

Using Auto Scaling Policies:

Scaling policies can dynamically adjust the number of instances in an Auto Scaling group based on metrics like CPU utilization.

Steps to Implement:

Step 1: Increase the maximum capacity of the Auto Scaling group (e.g., from 2 to a higher value like 5).

Step 2: Create a scaling policy:

Use a target tracking scaling policy with a threshold of 80% CPU utilization.

When the CPU usage exceeds 80%, additional instances will be launched automatically.

Step 3: Monitor scaling behavior and adjust thresholds or capacities if necessary.

AWS References:

Target Tracking Scaling Policies:Scaling Policies for Auto Scaling Groups

Dynamic Scaling Best Practices:Dynamic Scaling in Auto Scaling

Why Other Options Are Incorrect:

Option A: Deploying additional instances outside the Auto Scaling group is not scalable and defeats the purpose of automation.

Option B: Switching to burstable instances does not resolve the issue since the workload is CPU-bound and consistently high.

Option D: Increasing desired capacity does not account for the unpredictability of peak periods, as it sets a static scaling behavior rather than dynamic.

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.

# 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

https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-instance-protection.html

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.

To ensure comprehensive and automated security scanning across multiple AWS accounts:

Security Hub Administrator Account: Designate one account within AWS Organizations as the Security Hub administrator account. This centralizes security findings management.

Automate Account Association: Configure Security Hub to automatically associate new accounts in the organization as member accounts. This ensures all new and existing accounts are continuously monitored under the same security policies.

Enable CIS Benchmark Scans: Within Security Hub, enable the CIS AWS Foundations Benchmark standard. This automatically scans all member accounts against this set of security best practices and compliance standards.

This configuration provides an operationally efficient and scalable way to manage security and compliance across an extensive AWS environment, leveraging the native integration of AWS services.

When troubleshooting inability to access an EC2 instance from the internet, you should:

A: Verify that the security group rules allow inbound HTTP and HTTPS traffic on ports 80 and 443. Security groups act as a virtual firewall to control the traffic to instances.

D: Check that outbound rules in the network ACL allow traffic for ephemeral ports 1024-65535. This is crucial for return traffic from web requests, which typically use these higher port numbers for responses.

E: Confirm that any software-based firewalls on the instance (such as Windows Firewall or iptables in Linux) are configured to allow inbound traffic on HTTP and HTTPS. These steps will ensure that the web server is correctly configured to receive and respond to web traffic from the internet. AWS provides guidelines on these configurations in their documentation on security groups EC2 Security Groups and network ACLs Network ACLs.

To route traffic to the Network Load Balancer (NLB) using Amazon Route 53 cost-effectively, creating an alias record is the best solution.

Alias Record:

Alias records are a Route 53-specific extension to DNS functionality.

They provide a way to map a domain name to an AWS resource, such as an NLB, without incurring additional charges.

Steps to Implement:

Open the Route 53 console.

Select the hosted zone and choose "Create Record Set."

Choose "Alias" and select the NLB from the drop-down list.

Creating Alias Records

AWS Systems Manager State Manager is a service that allows you to automate the process of keeping your EC2 instances in a defined state, including installing software at launch or on a schedule.

From the AWS Systems Manager documentation:

You can use State Manager to bootstrap instances with software, apply configurations at launch, and maintain state across your fleet.

This is the most operationally efficient way to install software during instance launch.

Because the instance is:

In an isolated subnet (no internet or VPN access)

And you're not using Systems Manager

The best option is to use EC2 Instance Connect Endpoint, which allows SSH access to EC2 instances in private subnets without NAT or VPN.

From EC2 Instance Connect Endpoint documentation:

EC2 Instance Connect Endpoint enables secure connectivity to EC2 instances in private subnets without needing a public IP, bastion host, or VPN.

To handle the increased message load with minimal operational effort, implementing an Amazon Simple Queue Service (SQS) queue between the frontend and backend is an ideal solution. SQS decouples the frontend and backend by queuing messages, enabling the backend to process messages at its own pace without losing any.

SQS Queue: Acts as a buffer, ensuring messages are not lost if the backend application cannot immediately process them.

Decoupling: With SQS, the frontend can continue sending messages without concern for the backend's processing speed, providing a scalable solution with minimal management requirements.

Low Operational Overhead: SQS is fully managed, reducing the need for infrastructure management.

To automatically remediate security groups that allow unrestricted SSH access, the following configuration is recommended:

AWS Config Managed Rule (restricted-ssh):This rule checks whether security groups disallow unrestricted incoming SSH traffic. If a security group allows SSH access from 0.0.0.0/0 or ::/0, it is considered noncompliant.

AWS Systems Manager Automation Runbook (AWS-DisableIncomingSSHOnPort22):This runbook removes rules that allow unrestricted incoming SSH traffic on TCP port 22 for specified security groups. By associating this runbook with the AWS Config rule, noncompliant security groups can be automatically remediated without manual intervention.

This setup ensures that any security group violating the SSH access policy is promptly corrected, enhancing the security posture of the EC2 instances.

The issue where EC2 instances show up as healthy in the Auto Scaling group but unhealthy in the ALB target group is likely due to the target group health check being configured with an incorrect port or path.

Health Checks:

ALB target groups use health checks to determine the health of instances. These health checks are configured with a specific port and path.

If the health check configuration does not match the actual application endpoint on the instances, the instances will fail the health check.

Troubleshooting Steps:

Verify the health check settings for the target group in the ALB. Ensure the port and path are correctly configured to match the application on the EC2 instances.

Adjust the settings if necessary and monitor the health status of the instances in the target group.

To optimize the cost of a computing environment consisting of control nodes that are always on and task nodes that operate for a limited number of hours each day, consider the following strategies:

Purchase EC2 Instance Savings Plans for the Control Nodes: Since the control nodes are required to be operational 24/7, purchasing EC2 Instance Savings Plans is a cost-effective choice. These plans provide a lower price compared to on-demand instances, in exchange for a commitment to a consistent amount of usage (measured in $/hour) for a one or three-year period.

Use Spot Instances for the Task Nodes: Given that task nodes are used for a shorter duration (4 hours a day) and presumably can tolerate interruptions, using Spot Instances can significantly reduce costs. Spot Instances offer unused EC2 capacity at a fraction of the regular price, which can lead to substantial cost savings. Additionally, configure the system to fall back to On-Demand Instances during periods when Spot Instances are not available to ensure availability.

This combination leverages cost savings for continuous use and flexible, lower-cost options for intermittent use, optimizing overall operational costs efficiently.

CloudFront provides built-in viewer device detection headers, including:

CloudFront-Is-Mobile-Viewer

CloudFront-Is-SmartTV-Viewer

CloudFront-Is-Tablet-Viewer

From the CloudFront origin request policies documentation:

You can configure CloudFront to forward these device type headers to the origin so that different content (e.g., lower-resolution images for mobile) can be served and cached separately.

This allows differentiated caching based on the viewer's device type.

The VolumeQueueLength metric being high indicates the volume can’t process I/O operations fast enough, leading to performance degradation.

From Amazon EBS Performance Guide:

For gp3 volumes, performance can be adjusted by increasing IOPS or throughput independently of storage size.

The gp3 volume type allows provisioning up to:

16,000 IOPS

1,000 MB/s throughput

❌ Why the other options are incorrect:

A: ElastiCache is a caching layer and doesn't attach to EBS volumes.

B: Auto-Enabled IO is only relevant when IO is disabled due to volume-level issues, not performance.

D: Enhanced networking helps network performance, not disk I/O latency.

To meet the requirement of consistent performance of 10,000 IOPS with the least cost, the SysOps administrator should use a General Purpose SSD (gp3) Amazon EBS volume:

General Purpose SSD (gp3) EBS Volume:

The gp3 volume type can be provisioned with the required IOPS without the need for additional capacity, making it a cost-effective solution compared to Provisioned IOPS SSD (io1) volumes.

Objective:

Automate remediation of security groups that allow unrestricted SSH access.

Using AWS Config Automatic Remediation:

AWS Config allows rules to have automatic remediation actions.

The remediation action AWS-DisableIncomingSSHOnPort22 is a managed action specifically designed to restrict unrestricted SSH access.

Steps to Implement:

Step 1: Open the AWS Config console.

Step 2: Identify the rule that checks for unrestricted SSH access (e.g., security-group-restricted-ssh).

Step 3: Enable automatic remediation:

Attach the managed remediation action AWS-DisableIncomingSSHOnPort22 to the rule.

Specify necessary IAM roles and permissions for the remediation action.

Step 4: Test the rule and remediation action on a noncompliant security group.

AWS References:

AWS Config Managed Rules:AWS Config Rules

Automatic Remediation:AWS Config Remediation

Why Other Options Are Incorrect:

Option A: Requires manual configuration of alarms and Lambda functions, which is less operationally efficient than using managed remediation.

Option C and D: Custom Lambda functions and EventBridge rules are unnecessary when AWS provides a managed remediation action.

To efficiently monitor and identify noncompliant resources in terms of tagging within AWS, using AWS Config with a managed rule for required tagging is most appropriate:

AWS Config Setup: Configure AWS Config to monitor and record configurations of AWS resources within your environment.

Managed Rule for Required Tags: Utilize the "required-tags" managed rule in AWS Config, which checks whether your resources have the specific tags you define as mandatory. This rule can be customized to specify which tags are required and can automatically evaluate all existing and new resources in your environment.

Compliance Reporting: AWS Config provides detailed compliance reporting that helps you identify resources that do not meet the tagging requirements, facilitating easy remediation.

This approach leverages AWS Config’s capabilities for continuous monitoring and evaluation without needing to write custom code or manage additional services, providing an operationally efficient solution for compliance management.

To use the static website as a backup to the web application and ensure automated failover, the SysOps administrator should set up failover routing policies in Amazon Route 53.

Failover Routing Policies:

Route 53 failover routing allows you to route traffic to a primary resource when it is healthy and automatically failover to a secondary resource when the primary becomes unhealthy.

Steps to Implement:

Primary Failover Record: Create a primary failover routing policy record and set the value to the ALB. Associate this record with a Route 53 health check that monitors the ALB.

Secondary Failover Record: Create a secondary failover routing policy record and set the value to the static website.

Amazon Route 53 Failover Routing

When using the RequestCountPerTarget metric for scaling in an Auto Scaling group, the behavior of instance scaling follows specific rules set by Auto Scaling policies and cooldown periods:

Scaling Trigger: The Auto Scaling group triggers a scaling action whenever the RequestCountPerTarget exceeds the predefined limit set in the scaling policy.

Cooldown Period: After launching an EC2 instance due to a scaling action, the Auto Scaling group enters a cooldown period. During this period, despite further breaches of the threshold, no additional instances will be launched. This is designed to give the newly launched instance time to start and begin handling traffic, preventing the Auto Scaling group from launching too many instances too quickly.

This mechanism helps maintain efficient use of resources by adapting to changes in load while avoiding rapid, unnecessary scaling actions.

 Lambda Function to Rotate IAM Access Keys:

A Lambda function can be used to automate the rotation of IAM access keys based on their age.

Steps:

Write a Lambda function that checks the age of IAM access keys.

The function should rotate keys that are at least 30 days old.

Deploy the Lambda function.

 Amazon EventBridge Rule:

EventBridge can trigger the Lambda function periodically and when a new key is created.

Steps:

Create an EventBridge rule that triggers the Lambda function on a schedule (e.g., daily) and on IAM key creation events.

Rotating Access Keys for IAM Users, Amazon EventBridge

To enable automatic failover for RDS (MySQL in this case), you must configure it as a Multi-AZ deployment.

From Amazon RDS Multi-AZ documentation:

Multi-AZ deployments provide high availability and automatic failover support.

❌ Why other options are incorrect:

A: Changing engine to PostgreSQL does not help with failover.

C: Read replicas are used for scaling reads, not failover.

D: Automated backups help with point-in-time recovery, not failover.

To provision AWS accounts for each team with a defined baseline and governance guardrails in a scalable and efficient way, using AWS Control Tower is the best solution.

AWS Control Tower:

AWS Control Tower provides a straightforward way to set up and govern a secure, multi-account AWS environment based on best practices.

It uses Account Factory, a feature that automates the creation of new AWS accounts with predefined configurations.

Creating Accounts with Control Tower:

Navigate to the AWS Control Tower console.

Use Account Factory to create a new account.

Customize the account template to include the necessary configurations, such as organizational units (OUs), guardrails, and baselines.

Advantages:

Ensures consistent security and compliance across all accounts.

Automates account creation and configuration, saving time and reducing errors.

AWS Control Tower

Setting Up Account Factory

To achieve a limited rollout of the new website to 20% of the company's customers using Amazon Route 53, a weighted routing policy is the most appropriate solution.

Weighted Routing Policy:

Weighted routing lets you associate multiple resources with a single domain name and choose how much traffic is routed to each resource.

Configuration:

Open the Route 53 console.

Select the hosted zone and choose "Create Record Set."

Create two records for your domain:

One record for the original resource with a weight of 80.

Another record for the new resource with a weight of 20.

Amazon Route 53 Weighted Routing

Since the EC2 instance is attempting to access the internet using HTTP (port 80) but is configured only to allow HTTPS (port 443) traffic, the security group needs adjustment:

Security Group Configuration: The outbound rules of the security group associated with the EC2 instance must allow traffic over HTTP. Add an outbound rule that enables port 80 to destination 0.0.0.0/0. This rule will allow the instance to send HTTP requests to any IP address on the internet.

Test Connectivity: After updating the security group, test the connectivity using the curl command again to ensure the configuration allows internet access via HTTP.

This change is necessary because the existing security group configuration does not permit outbound HTTP traffic, which is essential for accessing websites using HTTP.

https://docs.aws.amazon.com/vpc/latest/userguide/egress-only-internet-gateway.html

To allow outbound IPv6 traffic from instances in your VPC to the internet, but prevent inbound traffic from the internet, you should use an egress-only internet gateway.

Egress-Only Internet Gateway:

An egress-only internet gateway is a horizontally scaled, redundant, and highly available VPC component that allows outbound communication over IPv6 from instances in your VPC to the internet and prevents the internet from initiating an IPv6 connection with your instances.

Routing Configuration:

Open the Amazon VPC console.

Select the route table associated with your VPC.

Add a route for IPv6 traffic (destination ::/0) to the egress-only internet gateway.

Egress-Only Internet Gateways

Routing for IPv6 Traffic

An SCP applied to the application OU that denies ec2:RunInstances when the CostCenter-Project tag is missing ensures that all accounts in the OU adhere to the tagging policy. This approach is centralized and applies only to the intended OU.

To resolve DNS across VPCs in different accounts, you should:

Authorization: In Account B, initiate a VPC association authorization for the private hosted zone. This action allows another AWS account to associate a VPC with this hosted zone.

Association: In Account A, after receiving the authorization from Account B, associate its VPC with the private hosted zone that exists in Account B. This step will enable EC2 instances within the VPC in Account A to resolve DNS records hosted in Account B.

AWS Documentation Reference:

AWS provides detailed guidance on associating VPCs with private hosted zones across accounts in their documentation: Associating VPCs and Private Hosted Zones Across Accounts.

To securely connect to the S3 buckets over a private connection from EC2 instances without incurring additional costs, the SysOps administrator can create a gateway VPC endpoint.

Create a Gateway VPC Endpoint:

Navigate to the VPC console.

Create a gateway VPC endpoint for Amazon S3.

AWS CloudFormation StackSets allows you to deploy a single CloudFormation template across multiple AWS accounts and Regions. By using automatic deployments with StackSets:

New Accounts: When a new account is added to the organization or a specific organizational unit (OU), the StackSet automatically deploys the specified resources.

Consistency: Ensures that all accounts have a consistent base configuration.

Operational Efficiency: Reduces manual intervention, as deployments are handled automatically.

This method provides a scalable and efficient way to enforce baseline configurations across an organization.

Amazon FSx for Windows File Server provides a fully managed, highly available, and native Windows file system compatible with the SMB protocol, ideal for Windows workloads requiring shared access.

Multi-AZ File System: Ensures high availability across multiple Availability Zones.

Native Windows Capabilities: Allows instances to map file shares and access files using Windows storage features, offering strong consistency and performance for shared files.

Other options, like Amazon S3 and Amazon EFS, either lack native Windows integration or do not offer the desired consistency and high availability for shared file systems in a Windows environment.

To restrict access to an application based on geographic location (France in this case), the appropriate routing policy in Amazon Route 53 is geolocation routing. This policy allows you to specify traffic routing based on the geographic location of your users:

B: Use a geolocation routing policy. Select France as the location in the record. This ensures that only DNS queries originating from France are routed to the application, fulfilling the requirement to limit access to users within France initially. More information about setting up geolocation routing can be found in the AWS Route 53 documentation on geolocation routing Amazon Route 53 Geolocation Routing.

Objective:

Resolve the failure of the CloudFormation Auto Scaling group resource creation due to a missing wait condition signal.

cfn-signal:

The cfn-signal command is used in user data scripts to signal CloudFormation that the resource has been successfully created or configured.

This ensures the stack creation process continues as expected.

Steps to Implement:

At the end of the user data script in the EC2 launch template:

Add the command: cfn-signal --stack --resource --region

Replace , , and with appropriate values.

AWS References:

cfn-signal:Using cfn-signal to Signal Completion

Why Other Options Are Incorrect:

Option B: While port 443 is necessary for CloudFormation signaling, the main issue is the absence of cfn-signal.

Option C: Reducing DesiredCapacity may bypass the error but does not solve the root cause.

Option D: Associating a public IP may help connectivity but is unrelated to the wait condition.

Step-by-Step Explanation:

Understand the Problem:

There are two applications, one in an on-premises data center and the other on an Amazon EC2 instance.

DNS resolution fails when the on-premises application tries to connect to the EC2 instance.

The goal is to implement DNS resolution between on-premises and AWS resources.

Analyze the Requirements:

Need to resolve the hostname of the EC2 instance from the on-premises network.

Utilize the existing AWS Site-to-Site VPN connection for DNS queries.

Evaluate the Options:

Option A: Set up an Amazon Route 53 inbound resolver endpoint with a forwarding rule for the onprem.private hosted zone.

This allows DNS queries from on-premises to be forwarded to Route 53 for resolution.

The resolver endpoint is associated with the VPC, enabling resolution of AWS resources.

Option B: Set up an Amazon Route 53 inbound resolver endpoint without specifying the forwarding rule.

This option does not address the specific need to resolve onprem.private DNS queries.

Option C: Set up an Amazon Route 53 outbound resolver endpoint.

Outbound resolver endpoints are used for forwarding DNS queries from AWS to on-premises, not vice versa.

Option D: Set up an Amazon Route 53 outbound resolver endpoint without specifying the forwarding rule.

Similar to Option C, this does not meet the requirement of resolving on-premises queries in AWS.

Select the Best Solution:

Option A: Setting up an inbound resolver endpoint with a forwarding rule for onprem.private and associating it with the VPC ensures that DNS queries from on-premises can resolve AWS resources effectively.

Amazon Route 53 Resolver

Integrating AWS and On-Premises Networks with Route 53

Using an Amazon Route 53 inbound resolver endpoint with a forwarding rule ensures that on-premises applications can resolve EC2 instance hostnames effectively.

Using the ALB’s RequestCount metric will allow the SysOps administrator to collect information about total requests for a 2-week period and determine when requests exceeded the threshold of 100 requests per second. Configuring a time range of 2 weeks and a period of 1 minute will ensure that the data can be accurately examined to determine peak traffic times and volumes.

To efficiently manage and automate the creation and termination of development environments:

AWS CloudFormation Templates:

Provide a standardized CloudFormation template for developers to create identical development environments.

The most operationally efficient solution to ensure that administrator passwords for Amazon RDS DB instances are changed at least annually is to use AWS Secrets Manager with automatic rotation.

AWS Secrets Manager:

AWS Secrets Manager helps you protect access to your applications, services, and IT resources without the upfront cost and complexity of managing your own hardware security infrastructure.

Secrets Manager enables you to rotate, manage, and retrieve database credentials, API keys, and other secrets throughout their lifecycle.

Configure Automatic Rotation:

Store the database credentials in AWS Secrets Manager.

Configure the secret to rotate automatically every 365 days.

AWS Secrets Manager provides built-in integration for rotating credentials for supported databases, including Amazon RDS.

Steps to Configure:

Open the Secrets Manager console.

Create a new secret and provide the necessary database credentials.

Enable automatic rotation and set the rotation interval to 365 days.

Secrets Manager will handle the rotation process, updating the credentials in the database and ensuring they are securely stored.

AWS Secrets Manager

Rotating Your AWS Secrets Manager Secrets

One possible cause for the failure of the CloudFormation template to create an EC2 instance in the us-west-2 Region is that the Amazon Machine Image (AMI) ID referenced in the template could not be found in the us-west-2 Region. This could be due to the fact that the AMI is not available in that region, or the credentials used to access the AMI were not configured properly. The other options (resource tags defined in the CloudFormation template are specific to the us-east-I Region, the cfn-init script did not run during resource provisioning in the us-west-2 Region, and the IAM user was not created in the specified Region) are not valid causes for this failure.

For high-performance computing (HPC) applications requiring minimal latency between nodes, using a placement group strategy is crucial.

Cluster Placement Group:

Provides low-latency network performance within a single Availability Zone by placing instances close together on the network.

Suitable for applications that require high throughput or low latency.

Partition Placement Group:

Helps reduce the impact of hardware failures by dividing instances into partitions, where each partition can be placed on distinct racks in the data center.

Suitable for applications that need high availability and fault tolerance.

Setting Up Placement Groups:

Create a Placement Group:

Open the Amazon EC2 console at Amazon EC2 Console.

In the navigation pane, choose Placement Groups.

Choose Create placement group, specify the name, and choose either Cluster or Partition as the strategy.

Launch Instances:

When launching new instances, specify the placement group name to ensure they are placed accordingly.

Placement Groups

Creating and Managing Placement Groups

Understand the Problem:

A user attempts to deploy a CloudFormation template to create an S3 bucket but the stack creation fails.

The user authenticates using Active Directory credentials.

Analyze the Requirements:

Identify permissions required for successful CloudFormation stack creation.

Evaluate the Options:

Option A: The user's IAM policy does not allow the cloudformation:CreateStack action.

Without this permission, the user cannot create CloudFormation stacks.

Option B: The user's IAM policy does not allow the cloudformation:CreateStackSet action.

StackSet is used for managing stacks across multiple accounts and regions, not relevant for a single stack creation.

Option C: The user's IAM policy does not allow the s3:CreateBucket action.

This permission is required to create an S3 bucket as part of the stack.

Option D: The user's IAM policy explicitly denies the s3:ListBucket action.

This permission is not required for bucket creation but for listing existing buckets.

Option E: The user's IAM policy explicitly denies the s3:PutObject action.

This permission is required to put objects in a bucket, not to create the bucket.

Select the Best Solution:

Option A and C: The user must have permissions for cloudformation:CreateStack and s3:CreateBucket to successfully create the stack and the S3 bucket.

AWS CloudFormation Permissions

IAM Policies and Permissions

Ensuring the user has the required permissions for cloudformation:CreateStack and s3:CreateBucket is crucial for successful stack creation.

To alleviate performance degradation on a heavily queried Amazon Aurora DB cluster:

A: Create an Aurora Replica node and implement an Auto Scaling policy based on CPU utilization. Ensure all reporting requests use the read-only connection string to redirect read queries to the replica. This setup alleviates the load on the primary DB instance by balancing read traffic, which can significantly improve stability during periods of high demand. Aurora Replicas are ideal for scaling read operations and can improve the performance of the primary instance by offloading read requests. More details on Aurora Replicas and their benefits can be found in the AWS documentation on Aurora Replicas Amazon Aurora Replicas.

In this scenario, the issue is that the EC2 instances are marked healthy by status checks, but the website is still intermittently failing, returning HTTP 500 errors.

This indicates that the OS-level checks are passing, but the application is not behaving properly. To resolve this, the Auto Scaling group must use ALB (ELB) health checks which verify application-level health, not just EC2 status.

From the Auto Scaling User Guide:

By default, an Auto Scaling group uses EC2 instance status checks to determine the health state of an instance. You can optionally configure the Auto Scaling group to use Elastic Load Balancing health checks in combination with EC2 status checks.

These health checks allow Auto Scaling to detect application failures and replace unhealthy instances automatically.

❌ Why the other options are incorrect:

A. Network Load Balancer is for TCP-level traffic and does not solve HTTP 500 errors.

C. Sticky sessions are used for session persistence and don’t solve server errors.

D. Installing CloudWatch agents and rebooting is reactive and not an automated health check replacement system.

You might want to use Transfer Acceleration on a bucket for various reasons: ->Your customers upload to a centralized bucket from all over the world. ->You transfer gigabytes to terabytes of data on a regular basis across continents. ->You can't use all of your available bandwidth over the internet when uploading to Amazon S3." https://docs.aws.amazon.com/AmazonS3/latest/userguide/transfer-acceleration.html

Aurora databases can be exported to S3 using the StartExportTask API, and the exported files can then be replicated cross-account and cross-region via S3 replication rules.

From RDS Export to S3 documentation:

You can export data to Amazon S3 from a snapshot using the StartExportTask API.

To automate, use Amazon EventBridge Scheduler and set up replication rules on the destination bucket.

This offers low operational overhead and full automation.

Enabling Instance Scale-In Protection:

Instance scale-in protection prevents Auto Scaling from terminating specific instances.

Steps:

Go to the AWS Management Console.

Navigate to EC2 and select "Auto Scaling Groups."

Select your Auto Scaling group.

Go to the "Instance management" tab.

Select the instances you want to protect and click "Actions."

Choose "Enable scale-in protection."

This ensures that instances are not terminated during troubleshooting.

Instance Scale-In Protection

To refer to resources created by the first CloudFormation template in the second template with minimal administrative effort, using the export and import functionality is the most efficient approach.

Exporting Outputs in the First Template:

In the first CloudFormation template, add an Outputs section to export the required values.

Use the Export field to specify the name of the exported value.

Example:

Outputs:

VPCID:

Description: The VPC ID

Value: !Ref MyVPC

Export:

Name: VPCID

Importing Values in the Second Template:

In the second CloudFormation template, use the Fn::ImportValue function to import the exported values from the first template.

Example:

Resources:

MySubnet:

Type: AWS::EC2::Subnet

Properties:

VpcId: !ImportValue VPCID

Efficiency and Best Practices:

This method ensures a clean separation of resources and allows easy reference to outputs from other stacks.

It simplifies the management and deployment process by leveraging CloudFormation's built-in export and import mechanisms.

AWS CloudFormation Exporting Stack Output Values

AWS CloudFormation Importing Values

To host a static website on Amazon S3, the SysOps administrator needs to configure the bucket for public access and set up the static website hosting. Here's how to complete this process:

Turn off "Block all public access": Amazon S3 buckets have "Block all public access" settings enabled by default for security. Since the webpage needs to be accessible publicly, this setting must be disabled. This step is crucial to allow public read access to the web content.

Set a bucket policy: After disabling "Block all public access," set a bucket policy that explicitly allows public read access to the S3 bucket. This policy should allow the s3:GetObject action for everyone, which can be set by specifying "Principal": "*". This policy ensures that anyone can view the webpage but does not grant permissions to modify or delete the content.

Create an index.html document and configure static website hosting: The next step is to create an index.html file, which will serve as the entry point of the website. After creating this file, upload it to the bucket. Then, configure the bucket for static website hosting through the S3 management console. This setting enables the S3 bucket to serve the webpage directly from the index.html file.

Combining these actions, the S3 bucket will be properly configured to host and serve the static website with minimal operational overhead and maximum accessibility.

To implement a highly available database solution that is ideal for multi-tenant workloads, migrating the database to an Amazon Aurora DB cluster and adding an Aurora Replica is the most suitable solution.

Amazon Aurora:

A fully managed relational database engine that's compatible with MySQL and PostgreSQL.

Provides high availability and durability through multiple replicas and automated failover.

Aurora Replicas:

Aurora Replicas share the same storage as the primary instance, providing increased read throughput and high availability.

In the event of a primary instance failure, an Aurora Replica can be promoted to primary.

Implementation Steps:

Migrate the MySQL database to an Amazon Aurora DB cluster.

Add one or more Aurora Replicas to the cluster to distribute read traffic and enhance availability.

Amazon Aurora

High Availability for Amazon Aurora

For member accounts in AWS Organizations to receive notifications about estimated costs exceeding a predetermined amount, billing alerts must be enabled in the management/payer account.

Enable Billing Alerts in the Management Account:

Open the AWS Billing and Cost Management console at AWS Billing Console.

In the navigation pane, choose Billing preferences.

Under Billing preferences, ensure that Receive Billing Alerts is enabled.

Create a Budget and Set Up Notifications:

Open the AWS Budgets console at AWS Budgets Console.

Create a budget and configure it to monitor the estimated costs.

Set up notifications for when the budget thresholds are exceeded and specify the email addresses of the managers in the member accounts.

By enabling billing alerts in the management account, you allow member accounts to receive notifications about their estimated costs.

Setting Up Alerts and Notifications

Creating an AWS Budget

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: https://aws.amazon.com/cloudformation/

Here are the steps to configure an Amazon S3 bucket to serve a static error page in the event of a failure at the primary site:

Log in to the AWS Management Console and navigate to the S3 service in the us-east-2 Region.

Find the existing S3 bucket named lab-751906329398-26023898.com and click on it.

In the "Properties" tab, click on "Static website hosting" and select "Use this bucket to host a website".

In "Index Document" field, enter the name of the object that you want to use as the index document, in this case, "index.html"

In the "Permissions" tab, click on "Block Public Access", and make sure that "Block all public access" is turned OFF.

Click on "Bucket Policy" and add the following policy to allow public read access:

{

"Version": "2012-10-17",

"Statement": [

{

"Sid": "PublicReadGetObject",

"Effect": "Allow",

"Principal": "*",

"Action": "s3:GetObject",

"Resource": "arn:aws:s3:::lab-751906329398-26023898.com/*"

}

]

}

Now navigate to the Amazon Route 53 service, and find the existing hosted zone named lab-751906329398-26023898.com.

Click on the "A record" and update the routing policy to "Primary - Failover" and add the existing ALB as the primary record.

Click on "Create Record" button and create a new secondary failover alias record for the domain lab-751906329398-26023898.com that routes traffic to the existing S3 bucket.

Now, when the primary site (ALB) goes down, traffic will be automatically routed to the S3 bucket serving the static error page.

Note:

You can use CloudWatch to monitor the health of your ALB.

You can use Amazon S3 to host a static website.

You can use Amazon Route 53 for routing traffic to different resources based on health checks.

You can refer to the AWS documentation for more information on how to configure and use these services:

https://aws.amazon.com/s3/

https://aws.amazon.com/route53/

https://aws.amazon.com/cloudwatch/

Graphical user interface, application, Teams Description automatically generated

To improve RDS performance during peak traffic when resources are over-utilized due to read traffic, the SysOps administrator can take the following actions:

Add a Read Replica:

Amazon RDS Read Replicas provide enhanced performance and durability for database instances.

By creating a read replica, you can offload read traffic from the primary database instance to the replica.

This reduces the load on the primary instance and improves overall performance.

Amazon RDS Read Replicas

Modify the Application to Use Amazon ElastiCache for Memcached:

Amazon ElastiCache is a web service that makes it easy to deploy, operate, and scale an in-memory cache in the cloud.

By using ElastiCache for Memcached, you can cache frequently accessed data, reducing the number of read requests to the RDS instance.

This can significantly improve the performance of the database during peak traffic.

Here are the steps to configure Amazon EventBridge to meet the above requirements:

Log in to the AWS Management Console by using the AWS Management Console shortcut from the VM desktop. Make sure that you are logged in to the desired AWS account.

Go to the EventBridge service in the us-east-2 Region.

In the EventBridge service, navigate to the "Event buses" page.

Click on the "Create event bus" button.

Give a name to your event bus, and select "default" as the event source type.

Navigate to "Rules" page and create a new rule named "RunFunction"

In the "Event pattern" section, select "Schedule" as the event source and set the schedule to run every 15 minutes.

In the "Actions" section, select "Send to Lambda" and choose the existing AWS Lambda function named "LogEventFunction"

Create another rule named "SpotWarning"

In the "Event pattern" section, select "EC2" as the event source, and filter the events on "EC2 Spot Instance interruption"

In the "Actions" section, select "Send to SNS topic" and create a new standard Amazon SNS topic named "TopicEvents"

In the "Input Transformer" section, set the Input Path to {“instance” : “$.detail.instance-id”} and Input template to “The EC2 Spot Instance has been interrupted on account.

Now all Amazon EC2 events in the default event bus will be replayable for past 90 days.

Note:

You can use the AWS Management Console, AWS CLI, or SDKs to create and manage EventBridge resources.

You can use CloudTrail event history to replay events from the past 90 days.

You can refer to the AWS EventBridge documentation for more information on how to configure and use the service: https://aws.amazon.com/eventbridge/

Increasing the size of the 1 GiB EBS volumes will increase the IOPS capacity of the volumes, which will improve the I/O performance of the EBS volumes. This option does not require any changes to the instance types or EBS volume types, so it can be done quickly without the need for lengthy acceptance tests to validate that the company's applications will function properly.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/requesting-ebs-volume-modifications.html

The issue of "request timed out" when pinging the public IP address of the EC2 instance could be due to the Network ACL (NACL) inbound rules.

Check NACL Inbound Rules:

Network ACLs act at the subnet level and can explicitly allow or deny traffic to or from a subnet.

Ensure that the NACL associated with the subnet containing the EC2 instance has inbound rules that allow ICMP traffic (which is used for ping).

Example rule to allow inbound ICMP traffic:

Rule Number: 100

Type: ICMP

Protocol: 1

Port Range: N/A (ICMP doesn't use ports)

Source: 0.0.0.0/0 (or specific IP range)

Allow/Deny: ALLOW

For EBS volumes restored from snapshots to immediately achieve the required IOPS performance, Fast Snapshot Restore (FSR) can be utilized:

Enable FSR: Fast Snapshot Restore can be enabled on specific snapshots. This feature pre-warms the EBS volume created from a snapshot to its full performance level immediately after it is provisioned.

Operational Impact: By enabling FSR, any EBS volume created from these enabled snapshots will provide the provisioned IOPS performance right from the start, eliminating the performance lag that typically occurs as the data is lazily loaded from S3.

Cost Considerations: While FSR increases costs due to the pre-warming of data, it is justified by the need for immediate high performance, especially in environments where EBS volume responsiveness is critical to application performance.

This solution directly addresses the challenge of initial performance degradation and ensures that the EBS volumes can handle the required workload immediately upon restoration from a snapshot.

To share an encrypted Amazon RDS DB instance snapshot across accounts, the least administrative overhead involves directly managing permissions on the AWS KMS key and sharing the snapshot. Here’s how to do it:

Take a Snapshot: Initiate a snapshot of your Amazon RDS DB instance in the production account. This captures the current state of the database.

Modify KMS Key Policy: Adjust the policy of the KMS key used for encryption (identified by the alias 'production-rds-key') to grant the kms:Decrypt permission to the migration account’s root user. This step is crucial as it allows the migration account to use the same encryption key to decrypt the snapshot.

Share the Snapshot: Share the newly created snapshot with the migration account using the RDS console or AWS CLI. The migration account will now be able to see and use this snapshot to create a new RDS instance.

AWS Documentation Reference:

You can refer to the AWS documentation on sharing encrypted snapshots: Sharing Encrypted Snapshots.

To monitor and automatically respond to security groups allowing SSH access:

AWS Config: This service can be used to detect security groups that allow SSH access publicly (Option B). AWS Config continuously monitors and records your AWS resource configurations and allows you to automate the evaluation of recorded configurations against desired configurations.

AWS Systems Manager Automation: This can automatically execute actions like closing the port when a non-compliant security group is detected (Option D). It allows the execution of automated workflows that can respond to Config rule findings, ensuring immediate remediation actions such as closing ports. These two services combined offer a comprehensive solution to monitor, detect, and rectify unwanted security group configurations automatically. AWS documentation on AWS Config AWS Config and on Systems Manager Automation Systems Manager Automation provides additional insights.

"Scheduled scaling helps you to set up your own scaling schedule according to predictable load changes. For example, let's say that every week the traffic to your web application starts to increase on Wednesday, remains high on Thursday, and starts to decrease on Friday. You can configure a schedule for Amazon EC2 Auto Scaling to increase capacity on Wednesday and decrease capacity on Friday." https://docs.aws.amazon.com/autoscaling/ec2/userguide/schedule_time.html

To improve the performance of an Amazon Elastic File System (EFS) when users report slower file retrieval times, configuring the file system for Provisioned Throughput is an effective solution.

Login to AWS Management Console:

Open the Amazon EFS console at Amazon EFS Console.

Select the File System:

In the EFS console, select the file system that you want to modify.

Modify Throughput Settings:

Choose File system policy and then Manage file system policy.

Under Throughput mode, select Provisioned Throughput.

Specify the desired throughput in MiB/s based on your application's needs.

Apply Changes:

Save the changes to apply the new throughput settings to the file system.

Amazon EFS Performance

Managing Throughput Modes

If users are unable to connect to a specific Ubuntu EC2 instance using AWS Systems Manager Session Manager while other instances are accessible, the issue is likely due to IAM permissions:

Instance Profile Permissions: Ensure that the EC2 instance has the necessary IAM permissions to interact with Systems Manager. The AmazonSSMManagedInstanceCore managed policy includes permissions required for the SSM Agent on the instance to communicate with the AWS Systems Manager service.

Attach Managed Policy: Attach the AmazonSSMManagedInstanceCore policy to the IAM role that is associated with the Ubuntu instance's instance profile. This step is crucial as it authorizes the instance to use Systems Manager services, including Session Manager.

Verify Configuration and Connectivity: After updating the instance profile, verify that users can connect via Session Manager. This solution does not require any changes to network security settings like security groups.

By ensuring that the instance has the appropriate IAM permissions, you resolve issues related to access control and Systems Manager functionality, allowing authorized personnel to connect securely without using SSH or RDP.

The most operationally efficient way to monitor state changes in EC2 instances and notify the operations team is by using Amazon EventBridge. EventBridge can be configured with a rule that listens for state change events from EC2 instances. These events can then be directed to an Amazon Simple Notification Service (Amazon SNS) topic, which will distribute the notification to the relevant parties. This solution does not require deploying additional scripts or functions, thereby enhancing operational efficiency. Option B is correct. For more details, see the Amazon EventBridge documentation Amazon EventBridge.

The rejected traffic in the flow logs is due to the network ACL associated with the subnet not allowing outbound traffic for the ephemeral port range.

Network ACLs:

Network ACLs act as a firewall for controlling traffic in and out of one or more subnets.

By default, NACLs allow all inbound and outbound traffic, but custom NACLs require specific rules to allow traffic.

Ephemeral Ports:

Ephemeral ports are temporary ports used for client-side communication. The default range is 1024-65535.

Ensure that the network ACL allows outbound traffic on these ports.

Steps to Resolve:

Check the network ACL rules for the associated subnet.

Add outbound rules to allow traffic from the ephemeral port range (1024-65535).

Amazon VPC Network ACLs

https://docs.aws.amazon.com/vpc/latest/peering/vpc-peering-routing.html

When establishing a VPC peering connection between two VPCs, you need to update the route tables of both VPCs to allow traffic to flow between them.

Route Table of VPC A (10.0.0.0/16):

Local Route: This route is automatically created to allow traffic within the VPC.

Destination: 10.0.0.0/16, Target: Local

Peering Connection Route: This route directs traffic destined for VPC B (172.31.0.0/16) through the VPC peering connection.

Destination: 172.31.0.0/16, Target: pcx-12345

Route Table of VPC B (172.31.0.0/16):

Local Route: This route is automatically created to allow traffic within the VPC.

Destination: 172.31.0.0/16, Target: Local

Peering Connection Route: This route directs traffic destined for VPC A (10.0.0.0/16) through the VPC peering connection.

Destination: 10.0.0.0/16, Target: pcx-12345

VPC Peering Routing