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

Objective:

Retain system and application logs for 13 months.

Ensure logs are preserved independently of EC2 instance termination.

Make logs easily accessible during the retention period.

Steps to Implement (Following Option D):

Step 1: Create a CloudWatch Log Group:

Open the CloudWatch console and create a new log group.

Set the retention period to 13 months using the "Expire Events After" feature.

Step 2: Deploy the Unified CloudWatch Agent:

Install the CloudWatch agent on all EC2 instances hosting the workload. The agent provides unified logging capabilities for system and application logs.

Step 3: Configure the Agent to Push Logs:

Configure the agent to push logs (e.g., /var/log/messages, application logs) to the created log group.

Use the agent configuration file to specify log paths, log groups, and retention settings.

Step 4: Attach Necessary IAM Role:

Attach an instance profile with an IAM policy that grants the necessary permissions (logs:PutLogEvents, logs:CreateLogStream) to send logs to CloudWatch.

Step 5: Verify Logging:

Confirm that logs are being sent to the CloudWatch log group and are stored according to the 13-month retention policy.

AWS References:

Unified CloudWatch Agent:Install and Configure CloudWatch Agent

CloudWatch Log Retention:Setting Log Retention in CloudWatch

IAM Permissions for CloudWatch Logs:IAM Policies for CloudWatch Logs

Why Other Options Are Incorrect:

Option A and C: Suggest using Amazon S3 for log storage, which is valid but requires external mechanisms (e.g., scripts) for log transfer and lacks native querying tools.

Option B: Does not mention using the unified CloudWatch agent, which is required to efficiently push logs from EC2 instances to CloudWatch Logs.

The S3 bucket is being used as the origin for a CloudFront distribution. To serve content via CloudFront:

You must point the DNS record to the CloudFront domain name (e.g., d11111abcdef8.cloudfront.net)

Not directly to the S3 bucket, even if that's the origin

From CloudFront with S3 static website hosting:

To use CloudFront to serve your content, update your DNS settings so your domain name (CNAME) points to your CloudFront distribution.

Configuring Security Groups:

Security groups act as virtual firewalls for your instances to control inbound and outbound traffic.

Steps:

Go to the AWS Management Console.

Navigate to EC2.

Select "Security Groups" from the left-hand menu.

Find and select the security group associated with your EC2 instances.

Choose the "Inbound rules" tab and click "Edit inbound rules."

Add a rule to allow traffic from the security group associated with the NLB.

Type: Custom TCP (or the specific port your application uses)

Source: Select "Custom" and enter the ID of the NLB's security group.

This setup ensures that the EC2 instances accept traffic only from the NLB, enhancing security with minimal operational overhead.

AWS Security Groups

Step-by-Step Explanation:

Understand the Problem:

The application on a general-purpose EC2 instance experiences performance issues during I/O intensive tasks.

High VolumeQueueLength indicates a bottleneck in I/O operations.

Analyze the Requirements:

Improve disk I/O performance to handle intensive read/write operations.

Evaluate the Options:

Option A: Modify the instance type to be storage optimized.

This could help but may not be necessary if increasing IOPS on the EBS volume resolves the issue.

Option B: Deselect Auto-Enable Volume I/O.

This option is not relevant to addressing high VolumeQueueLength.

Option C: Modify the volume properties to increase the IOPS.

Increasing IOPS directly addresses the I/O performance bottleneck.

Option D: Enable enhanced networking.

Enhanced networking improves network performance but not disk I/O performance.

Select the Best Solution:

Option C: Increasing the IOPS of the EBS volume directly addresses the high VolumeQueueLength and improves I/O performance.

Amazon EBS Volume Types

Optimizing EBS Performance

Modifying the volume properties to increase the IOPS ensures that the application can handle intensive read/write operations more effectively.

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 transition the Amazon Elasticsearch Service (Amazon ES) domain to a highly available, production-grade deployment:

Cluster Configuration:

Use a cluster of six data nodes to handle data ingestion and querying.

Distribute these nodes across three Availability Zones (AZs) for high availability and fault tolerance.

To maintain a documented trail of any changes made to the security groups and receive notifications, AWS Config is the best solution.

AWS Config:

AWS Config continuously monitors and records your AWS resource configurations and allows you to automate the evaluation of recorded configurations against desired configurations.

You can set up AWS Config to record changes to your security groups.

Setting Up AWS Config:

Open the AWS Config console and choose "Set up AWS Config."

Select the resource types you want to record (in this case, security groups).

Specify an Amazon S3 bucket to store configuration snapshots and history files.

Notifications:

Create an Amazon SNS topic for notifications about configuration changes.

Subscribe the SysOps administrator's email address to the SNS topic.

AWS Config

Setting Up AWS Config

AWS Systems Manager Maintenance Windows allow you to define a schedule for performing administrative tasks on your instances. By setting up a maintenance window:

Schedule Reboots:

Define a maintenance window outside business hours.

Register the EC2 instances as targets.

Assign the AWS-RestartEC2Instance Automation document to the task.

This setup ensures that instances are rebooted regularly, mitigating the effects of the memory leak until a permanent fix is implemented.

Step-by-Step Explanation:

Understand the Problem:

The application experiences slower performance during peak activity due to increased load on the Amazon Aurora DB cluster.

Performance issues occur primarily during search operations.

The goal is to improve performance and maximize resource efficiency.

Analyze the Requirements:

The solution should improve the performance of the platform.

It should maximize resource efficiency, which implies cost-effective and scalable options.

Evaluate the Options:

Option A: Deploy an Amazon ElastiCache for Redis cluster.

ElastiCache for Redis is a managed in-memory caching service that can significantly reduce the load on the database by caching frequently accessed data.

By modifying the application to check the cache before querying the database, repeated searches for the same information will be served from the cache, reducing the number of database reads.

This is efficient and cost-effective as it reduces database load and improves response times.

Option B: Deploy an Aurora Replica and use Auto Scaling.

Adding Aurora Replicas can help distribute read traffic and improve performance.

Aurora Auto Scaling can adjust the number of replicas based on the load.

However, this option may not be as efficient in terms of resource usage compared to caching because it still involves querying the database.

Option C: Use Provisioned IOPS.

Provisioned IOPS can improve performance by providing fast and consistent I/O.

This option focuses on improving the underlying storage performance but doesn't address the inefficiency of handling repeated searches directly.

Option D: Increase the instance size and use Auto Scaling.

Increasing the instance size can provide more resources to handle peak loads.

Aurora Auto Scaling can adjust instance sizes based on the load.

This option can be costly and may not be as efficient as caching in handling repeated searches.

Select the Best Solution:

Option A is the best solution because it leverages caching to reduce the load on the database, which directly addresses the issue of repeated searches causing performance problems. Caching is generally more resource-efficient and cost-effective compared to scaling database instances or storage.

Amazon ElastiCache for Redis Documentation

Amazon Aurora Documentation

AWS Auto Scaling

Using ElastiCache for Redis aligns with best practices for improving application performance by offloading repetitive read queries from the database, leading to faster response times and more efficient resource usage.

Content-MD5 Header:

The Content-MD5 header provides an MD5 checksum of the object being uploaded. Amazon S3 uses this checksum to verify the integrity of the object.

Steps:

When uploading an object to S3, calculate the MD5 checksum of the object.

Include the Content-MD5 header with the base64-encoded MD5 checksum value in the upload request.

This ensures that S3 can detect if the object is corrupted during the upload process.

PUT Object - Amazon Simple Storage Service

Retain the Security Group:

When deleting a CloudFormation stack, you can specify resources to be retained instead of deleted.

Steps:

Go to the AWS Management Console.

Navigate to CloudFormation and select the stack.

Choose to delete the stack.

In the deletion options, specify that the security group should be retained.

This will delete the stack but keep the security group, ensuring no impact on other applications.

Deleting a Stack

To prevent the EC2 instances and their data from being deleted when a CloudFormation stack is deleted:

DeletionPolicy Attribute: In the CloudFormation template that defines the EC2 instances, set the DeletionPolicy attribute to Retain for each EC2 instance resource. This setting ensures that when the CloudFormation stack is deleted, the EC2 instances are not terminated.

Impact of the Retain Policy: With this policy, all data on the instance, such as data on its attached EBS volumes, remains intact even after the stack deletion. The resources will remain in your AWS account and will need to be managed or deleted manually thereafter.

This approach is directly supported by AWS CloudFormation and provides a simple and effective way to protect EC2 instances and their data during stack deletions.

To set up notifications for when combined billing exceeds a certain threshold for all AWS accounts within an organization, follow these steps:

Enable Billing Alerts:

In the payer account, go to the Billing and Cost Management console.

Under "Billing preferences", enable the "Receive Billing Alerts" option.

Set Up a Billing Alarm in CloudWatch:

Navigate to the CloudWatch console.

Create a new billing alarm, specifying the threshold for the combined billing amount.

Set the alarm to publish a notification to an SNS topic when the threshold is breached.

Publish SNS Message:

Create an SNS topic to receive the billing alarm notifications.

Configure the billing alarm to send notifications to the SNS topic.

Setting Up a CloudWatch Billing Alarm

AWS Billing and Cost Management User Guide

To improve the high availability of an application that utilizes Amazon RDS and experiences failure when an Availability Zone becomes unavailable:

Multi-AZ Deployment for RDS: Enable Multi-AZ deployments for your Amazon RDS instance. This setting ensures that RDS automatically provisions and maintains a synchronous standby replica in a different Availability Zone.

Automatic Failover: In the event of a primary RDS instance failure, RDS will automatically failover to the standby so that database operations can resume quickly with minimal disruption.

High Availability Configuration: This configuration not only enhances the robustness of the database component but also ensures that the application remains operational even if one Availability Zone is experiencing issues.

Enabling Multi-AZ for RDS is crucial for maintaining high availability and ensuring that the application remains resilient in the face of AZ disruptions.

To securely connect to Amazon S3 buckets from Amazon EC2 instances over a private connection without incurring additional costs, you can use a gateway VPC endpoint for S3. This method allows you to create a single gateway VPC endpoint for all S3 buckets in the same region, ensuring secure, private communication.

Create a Gateway VPC Endpoint:

Navigate to the VPC console.

In the navigation pane, choose "Endpoints" and then click "Create Endpoint".

Select "AWS services" and then choose "com.amazonaws..s3" from the service name dropdown.

Select the VPC in which to create the endpoint and the appropriate route tables.

Click "Create endpoint".

Update the Route Tables:

The gateway VPC endpoint will automatically update the selected route tables to include routes that direct S3 traffic through the endpoint.

Ensure that the route tables associated with your subnets include routes for the S3 service pointing to the gateway VPC endpoint.

Verify the Configuration:

Ensure that instances in the VPC can access the S3 buckets using private IP addresses.

Check the routing configuration to confirm that traffic to S3 is routed through the gateway VPC endpoint.

Gateway VPC Endpoints for Amazon S3

Creating a Gateway Endpoint

To stop EC2 instances in a development environment when they are not in use, you can create a CloudWatch alarm based on CPU utilization.

Create CloudWatch Alarm:

Navigate to the CloudWatch console.

Select "Alarms" and click on "Create Alarm".

Choose the EC2 instance metric for CPU utilization.

Set the condition to trigger the alarm when the average CPU utilization is less than 5% for a continuous 30-minute period.

To enforce tag-based restrictions across multiple accounts in an OU, Service Control Policies (SCPs) are the best tool.

From SCP documentation:

You can deny access to APIs like ec2:RunInstances if a specific tag is not present using a condition such as Null:aws:RequestTag/CostCenter-Project: true.

By attaching the SCP to the application OU, only the accounts within that OU are impacted.

 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

Objective:

Provide a static IP address that the vendor can whitelist for accessing the application.

Using Network Load Balancer (NLB):

Unlike Application Load Balancers, NLBs support static IP addresses through Elastic IPs.

NLBs operate at the transport layer (Layer 4) and are ideal for use cases requiring a static IP.

Steps to Implement:

Step 1: Create an NLB in the same VPC as the application.

Step 2: Associate Elastic IP addresses with the NLB subnets.

Step 3: Update the target group to point to the existing EC2 instances.

Step 4: Update DNS records to map the application domain (www.example.com) to the NLB 's static IP or DNS name.

AWS References:

Elastic IPs with NLB:Static IPs for NLB

NLB vs. ALB:Comparison of Load Balancers

Why Other Options Are Incorrect:

Option A: ALBs do not support Elastic IPs.

Option B: AWS WAF is for web access control, not providing static IPs.

Option C: VPC endpoints do not replace load balancers and are unrelated to static IP requirements.

gp3 volumes provide higher performance and flexibility than gp2. With gp3, you can provision IOPS and throughput independently of storage size.

From the Amazon EBS documentation:

gp3 volumes deliver baseline performance of 3,000 IOPS, and you can provision up to 16,000 IOPS and 1,000 MB/s, regardless of volume size.

Amazon FSx for Windows File Server provides a fully managed native Microsoft Windows file system that supports the SMB protocol and Windows ACLs, ensuring compatibility with existing applications and processes. Using a Multi-AZ deployment ensures high availability by providing automatic failover to a standby instance in a different Availability Zone.

Create Amazon FSx for Windows File Server:

Open the Amazon FSx console at Amazon FSx Console.

Choose Create file system.

Select Amazon FSx for Windows File Server, then click Next.

Configure File System Settings:

In the File system details section, provide the necessary details such as Deployment type, Storage capacity, and Throughput capacity.

Select Multi-AZ deployment to ensure high availability.

Choose the Windows authentication method, either AWS Managed Microsoft AD or Self-managed Microsoft AD.

Network & Security Configuration:

Select the VPC, subnet, and security groups to attach to the file system.

Ensure subnets are in different Availability Zones for Multi-AZ configuration.

Review and Create:

Review the settings and click Create file system.

Access the File System:

Once the file system is created, you can map the network drive using the provided DNS name and manage permissions using Windows ACLs.

Amazon FSx for Windows File Server Documentation

Creating a Multi-AZ File System

Using a CloudWatch alarm with an EventBridge rule provides an automated, direct way to reboot the EC2 instance without extra components like SES or Lambda. This is a straightforward approach with low operational overhead.

To monitor and receive alerts when the EC2 instance service quota usage reaches 70% or more:

Service Quotas Console: Navigate to the Service Quotas console within AWS and identify the specific quota for EC2 instances.

Create a CloudWatch Alarm: Directly from the Service Quotas console, set up a CloudWatch alarm for the EC2 instance quota metric. Configure the alarm to trigger when the quota utilization reaches or exceeds 70%.

Notification Setup: Link this alarm to an Amazon SNS topic that will send a notification to relevant stakeholders or systems when the quota usage threshold is breached.

This method provides an automated, straightforward way to monitor resource limits and ensures that stakeholders are promptly notified, enabling them to take proactive measures to manage the quota and prevent service disruption.

To automate the execution of a Python script every night efficiently:

Convert Python Script to Lambda:

Create an AWS Lambda function and upload the Python script.

Ensure the function has the necessary IAM permissions to perform the required maintenance tasks.

Using AWS Systems Manager Patch Manager with a maintenance window is a best practice for automating OS patch management across instances in an Auto Scaling group.

Patch Manager: Allows for scheduled patching according to maintenance windows, ensuring minimal impact on application uptime.

RebootOption parameter: Setting this to RebootIfNeeded ensures patches are applied fully when a reboot is required.

AWS-RunPatchBaseline: This document automates the patching process and can be customized based on compliance requirements.

https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/custom-tags.html "User-defined tags are tags that you define, create, and apply to resources. After you have created and applied the user-defined tags, you can activate by using the Billing and Cost Management console for cost allocation tracking. "

To meet this requirement, the SysOps administrator should activate the company-defined tags as user-defined cost allocation tags. This will ensure that the tags appear on the billing report and that the resources can be tracked with the specific tags. The other options (activating the tags as AWS generated cost allocation tags, creating a new cost category and selecting the account billing dimension, and creating a new AWS Cost and Usage Report and including the resource IDs) will not meet the requirements and are not the correct solutions for this issue.

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

AWS CloudFormation StackSets extends the capability of stacks by enabling you to create, update, or delete stacks across multiple accounts and AWS Regions

If a Lambda function is not being invoked by an Amazon EventBridge (formerly CloudWatch Events) rule, the likely issue is a missing permission. The Lambda function needs permission to be invoked by the EventBridge rule.

Steps:

Add Permission to Lambda Function:

Open the AWS Lambda console.

Select your Lambda function.

Choose "Configuration" and then "Permissions".

Under the "Resource-based policy" section, add a policy that grants EventBridge permission to invoke your function.

Example policy:

json

Copy code

{

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

"Statement": [

{

"Effect": "Allow",

"Principal": {

"Service": "events.amazonaws.com"

},

"Action": "lambda:InvokeFunction",

"Resource": "arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME",

"Condition": {

"ArnLike": {

"AWS:SourceArn": "arn:aws:events:REGION:ACCOUNT_ID:rule/RULE_NAME"

}

}

}

]

}

Verify the EventBridge Rule:

Open the Amazon EventBridge console.

Select the rule that targets your Lambda function.

Ensure that the rule is correctly configured to match events and the target is your Lambda function.

AWS WAF (Web Application Firewall) is designed to protect web applications from common web exploits that could affect application availability, compromise security, or consume excessive resources. AWS WAF can help mitigate cross-site scripting (XSS) vulnerabilities by allowing users to create rules to filter specific types of HTTP requests.

Create a Web ACL:

Go to the AWS WAF & Shield console.

Click "Create web ACL" and specify a name and the AWS resource to protect (e.g., an Application Load Balancer).

Add Rules to Mitigate XSS:

Within the Web ACL, add a new rule.

Select "Rule builder" and choose a rule type. For mitigating XSS, use "AWS Managed Rules" or create a custom rule.

AWS Managed Rules include a predefined set for XSS that you can enable.

Configure the XSS Rule:

If using a custom rule, configure it to inspect requests and block any that contain XSS patterns.

Use regular expressions or specific patterns to identify malicious scripts.

Deploy the Web ACL:

Once configured, save the Web ACL.

Associate it with your Application Load Balancer or CloudFront distribution to start filtering requests.

Monitor and Adjust:

Monitor the requests being blocked by AWS WAF.

Adjust the rules as necessary to ensure legitimate traffic is not affected and the application remains protected.

AWS WAF Developer Guide

AWS WAF Managed Rules

The most likely reason for being unable to authenticate an AWS CLI call to an AWS service is the absence of an access key. AWS CLI requires an access key and secret key to authenticate requests.

Access Key and Secret Key:

AWS uses access keys to identify and authenticate the identity of the requester.

Ensure that the AWS CLI is configured with a valid access key and secret key.

Check AWS CLI Configuration:

Use the aws configure command to set up the AWS CLI with the necessary credentials.

Verify that the ~/.aws/credentials file contains the correct access key and secret key.

AWS CLI Configuration

Managing Access Keys

To enforce the use of approved EC2 instance configurations across different business units efficiently:

AWS Service Catalog: Utilize AWS Service Catalog to manage and govern commonly deployed IT services. Create a catalog of pre-approved products (in this case, EC2 instance configurations).

Publish Products: Define and publish EC2 instance configurations as products within the Service Catalog. These products will incorporate all the necessary and approved configurations, options, and software.

Launch Constraints: Assign launch constraints to these products, ensuring that users can only launch EC2 instances as defined by the pre-approved configurations.

Control Access: Grant business units access only to the Service Catalog for provisioning EC2 instances. This ensures they use only those configurations that comply with company policies and standards.

This approach not only standardizes resource deployment but also simplifies management and enhances compliance across the organization.

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

Weighted routing in Route 53 allows you to direct a percentage of traffic to different resources by configuring specific weights. For this requirement, you can:

Weighted Routing Policy: This is the most suitable approach for gradually rolling out a new version by controlling traffic distribution.

Weight Configuration: Setting a weight of 80 for the original resource and 20 for the new resource ensures that 80% of the traffic continues to go to the existing version, while 20% is directed to the new version.

Other routing policies, such as failover and multivalue answer, are not intended for traffic distribution based on percentage; they serve different use cases.

To meet the requirements of logging all access attempts to the S3 bucket and receiving immediate notification about any delete events, the company can enable S3 server access logging and set up an Amazon Simple Notification Service (Amazon SNS) notification for the S3 bucket. The S3 server access logs will record all access attempts to the bucket, including delete events, and the SNS notification can be configured to send an alert when a DeleteObject event occurs.

EventBridge supports event archiving and replay, allowing you to store events and replay them on demand to the original or new targets.

From Amazon EventBridge Replay documentation:

EventBridge archives allow you to retain events for a specified time and use replay to send events again to targets – useful when downstream systems fail.

This is ideal for reprocessing missed deliveries without modifying the original producer or consumer logic.

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.

AWS Config can continuously monitor and record your AWS resource configurations. It provides AWS Config rules that automatically check the configuration of AWS resources and notify you of compliance and non-compliance.

Steps:

Enable AWS Config:

Open the AWS Config console.

Follow the steps to set up AWS Config if it is not already enabled.

Add AWS Managed Rules:

In the AWS Config console, choose "Rules".

Add the s3-bucket-public-read-prohibited managed rule.

Configure the rule to check all S3 buckets.

Set Up SNS Notifications:

Create an Amazon SNS topic.

Subscribe your email or other communication channels to the SNS topic.

In AWS Config, configure the rule to send notifications to the SNS topic whenever there is a compliance change.

This approach ensures operational efficiency as AWS Config will automatically monitor S3 buckets and notify you through SNS if any bucket becomes publicly accessible.

To restrict access to content in specific countries using CloudFront, enabling the geo restriction feature in the CloudFront distribution is the most operationally efficient solution.

Geo Restriction in CloudFront:

CloudFront allows you to use geographic restrictions, also known as geo-blocking, to prevent users in specific geographic locations from accessing content that you're distributing through a CloudFront distribution.

Enabling Geo Restriction:

Go to the CloudFront console.

Select your distribution and click on "Restrictions."

Choose "Edit" and then enable "Geo restriction."

Specify the countries you want to restrict by selecting "Whitelist" or "Blacklist" and entering the appropriate country codes.

Operational Efficiency:

This method leverages CloudFront's built-in capabilities to restrict access at the edge locations, ensuring that unauthorized requests are blocked before reaching your origin.

It is a straightforward and scalable solution without requiring changes to your S3 bucket policy or application logic.

Using Geo Restriction to Restrict Access to Your Content

The simplest and most efficient solution to ensure that EC2 instances are restarted when CPU utilization exceeds 80% is to use Amazon CloudWatch alarms:

Create a CloudWatch Alarm: Navigate to the CloudWatch dashboard in the AWS Management Console and create a new alarm. Set the alarm to monitor the CPU utilization metric of the EC2 instances.

Set the Alarm Condition: Configure the alarm to trigger when the CPU utilization exceeds 80%. You can specify this threshold in the alarm settings.

Configure Alarm Actions: In the actions settings of the alarm, select the option to reboot the instance. This action ensures that the instance is automatically restarted whenever the alarm condition is met, without the need for manual intervention or additional scripts.

This method leverages AWS's native capabilities, minimizing operational overhead and eliminating the need for external tools or custom scripts.

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

Step-by-Step Explanation:

Understand the Problem:

CloudTrail must be re-enabled immediately if it is disabled.

Analyze the Requirements:

Implement an automatic solution to monitor and re-enable CloudTrail.

Evaluate the Options:

Option A: Add the AWS account to AWS Organizations and enable CloudTrail in the management account.

This provides centralized management but does not ensure automatic re-enabling of CloudTrail.

Option B: Create an AWS Config rule with automatic remediation.

AWS Config can monitor changes and automatically remediate by re-enabling CloudTrail.

Option C: Create an AWS Config rule that invokes a Lambda function.

This requires custom code, which is not preferred.

Option D: Create an EventBridge rule with a Systems Manager Automation document.

This can re-enable CloudTrail but is more complex compared to AWS Config’s built-in remediation.

Select the Best Solution:

Option B: Using AWS Config with automatic remediation ensures CloudTrail is re-enabled without writing custom code.

AWS Config Rules

Automatic Remediation with AWS Config

Creating an AWS Config rule with automatic remediation ensures that CloudTrail is immediately re-enabled if it is disabled.

Enable deletion protection for the DynamoDB tables:

Deletion protection is a feature that prevents accidental deletion of DynamoDB tables. When enabled, it requires an additional step to disable this protection before the table can be deleted.

Steps:

Go to the AWS Management Console.

Navigate to DynamoDB.

Select the table you want to protect.

Choose the "Overview" tab.

Under "Deletion protection," click "Enable deletion protection."

AWS DynamoDB Deletion Protection

Enable point-in-time recovery (PITR) for the DynamoDB tables:

PITR provides continuous backups of your DynamoDB tables. You can restore the table to any point in time within the last 35 days.

Steps:

Go to the AWS Management Console.

Navigate to DynamoDB.

Select the table you want to enable PITR for.

Choose the "Backups" tab.

Click on "Enable Point-in-Time Recovery."

If a table is accidentally deleted, you can restore it using PITR.

Go to the DynamoDB console.

Select "Backups" from the navigation pane.

Find the table backup and choose "Restore."

To change an EC2 instance type (e.g., from t3.large to c5.large):

You must stop the instance, change the instance type, then start it again.

From EC2 instance resize documentation:

Changing the instance type requires stopping and starting the instance, unless you're using Elastic Beanstalk or Auto Scaling groups with launch templates.

To delete the AWS CloudFormation stack without deleting the DynamoDB table, you need to apply a deletion policy to the DynamoDB resource. The Retain deletion policy ensures that the specified resource is not deleted when the stack is deleted. Instead, it is retained.

Steps:

Modify the CloudFormation Template:

Add a deletion policy to the DynamoDB table resource.

json

Copy code

{

"Resources": {

"MyDynamoDBTable": {

"Type": "AWS::DynamoDB::Table",

"DeletionPolicy": "Retain",

}

}

}

To meet the requirement of directing users to the Region closest to them and providing automated failover, the SysOps administrator should perform the following steps:

Create Amazon CloudWatch Alarms:

Create CloudWatch alarms that monitor the health of the ALB in each Region. This ensures that the system can detect unhealthy endpoints and trigger the failover mechanism.

To address the performance issues of a CPU-heavy application running on a t2.large EC2 instance, the best course of action is to upgrade to a compute-optimized instance. Compute-optimized instances provide a higher ratio of CPU resources compared to memory, making them ideal for applications that require high CPU performance.

Upgrade to a Compute-Optimized Instance:

Identify a suitable compute-optimized instance type, such as the c5.large, which offers better CPU performance compared to the t2.large.

Stop the current EC2 instance and change the instance type to the chosen compute-optimized instance.

To resolve DNS names for on-premises resources from EC2 instances in a VPC, you use Amazon Route 53 Resolver outbound endpoints to forward DNS queries to on-premises DNS servers.

From the Route 53 Resolver documentation:

Resolver outbound endpoints allow DNS queries from resources in your VPC to be forwarded to DNS servers in your on-premises network over Direct Connect or VPN.

Using AWS Systems Manager to schedule a maintenance window for restarting EC2 instances outside business hours provides a straightforward and automated approach.

AWS Systems Manager Maintenance Window: Allows for daily scheduling, ensuring that restarts occur consistently outside of business hours.

AWS-RestartEC2Instance Runbook: This runbook can be assigned to the maintenance window, automating the reboot process and minimizing manual intervention.

Reduced Disruption: The scheduled restart ensures the application remains operational during business hours.

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.

Amazon GuardDuty is a threat detection service that continuously monitors for malicious activity and unauthorized behavior to protect AWS accounts and workloads. It provides detailed monitoring for unauthorized access attempts, including console login attempts from unusual locations.

Amazon GuardDuty:

GuardDuty analyzes VPC flow logs, AWS CloudTrail logs, and DNS logs to detect suspicious activity.

It generates findings, such as UnauthorizedAccess

/ConsoleLoginSuccess, to alert administrators about potential security issues.

Setup:

Enable GuardDuty in your AWS account.

Configure GuardDuty to monitor unauthorized console logins.

Set up notifications for the relevant findings to alert administrators.

Amazon GuardDuty

GuardDuty Finding Types

To resolve issues with high disk I/O during the bootstrap process:

Increase EBS Volume IOPS: Higher IOPS allows the EBS volume to handle more input/output operations per second, which is critical for high I/O demands like downloading large Docker images.

Increase EBS Volume Throughput: Boosting throughput allows for faster data transfer rates, which is useful when the workload requires sustained high data throughput during initialization.

Increasing the instance size or changing the instance type is not necessary if the root cause is related specifically to EBS performance. Nitro instances generally provide higher performance and are well-suited for high I/O tasks.

Step-by-Step Explanation:

Understand the Problem:

The threat of ransomware encrypting and holding company data hostage.

Need to protect an Amazon S3 bucket.

Analyze the Requirements:

Ensure that data in the S3 bucket is protected against unauthorized encryption or deletion.

Evaluate the Options:

Option A: Deny Post, Put, and Delete on the bucket.

Denying these actions would prevent any uploads or modifications to the bucket, making it unusable.

Option B: Enable server-side encryption on the bucket.

Server-side encryption protects data at rest but does not prevent the encryption of data by ransomware.

Option C: Enable Amazon S3 versioning on the bucket.

S3 versioning keeps multiple versions of an object in the bucket. If a file is overwritten or encrypted by ransomware, previous versions of the file can still be accessed.

Option D: Enable snapshots on the bucket.

Amazon S3 does not have a snapshot feature; this option is not applicable.

Select the Best Solution:

Option C: Enabling Amazon S3 versioning is the best solution as it allows access to previous versions of objects, providing protection against ransomware encryption by retaining prior, unencrypted versions.

Amazon S3 Versioning

Best Practices for Protecting Data with Amazon S3

Enabling S3 versioning ensures that previous versions of objects are preserved, providing a safeguard against ransomware by allowing recovery of unencrypted versions of data.

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.

Amazon S3 Cross-Region Replication (CRR) is a feature that automatically replicates objects across AWS regions. When CRR is configured, certain aspects are replicated by default, and some are not. Here are the details:

Objects in the source S3 bucket for which the bucket owner does not have permissions: CRR does not replicate objects for which the bucket owner does not have permissions.

Objects that are stored in S3 Glacier: Objects in the S3 Glacier storage class are not replicated by CRR.

Objects that existed before replication was configured: Only objects created or modified after the replication configuration will be replicated. Objects that existed before the configuration are not replicated by default.

Object metadata: CRR replicates the object metadata along with the object to ensure that the replica in the destination bucket is as accurate as possible.

Amazon S3 Cross-Region Replication

Replication Configuration Examples

Increasing the IOPS for the gp3 EBS volume will address the high VolumeQueueLength by allowing more read/write operations, directly improving performance for I/O-intensive tasks. ElastiCache and enhanced networking do not directly affect EBS performance for this issue.

To monitor free space on Amazon EBS volumes attached to Microsoft Windows-based Amazon EC2 instances and receive email alerts before low storage space affects performance, follow these steps:

Install the Amazon CloudWatch Agent:

Download and install the CloudWatch agent on your Windows EC2 instances.

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.

When an AWS CloudFormation stack is in the DELETE_FAILED state due to the inability to delete a specific resource, such as an Amazon EC2 security group, the recommended approach is to use the DeleteStack operation with the RetainResources parameter. By specifying the resource (in this case, the security group) in the RetainResources parameter, CloudFormation will retain that resource and proceed to delete the rest of the stack.

This method is particularly useful when a resource cannot be deleted because it is being referenced by other resources outside the stack or due to dependencies that prevent its deletion. By retaining the problematic resource, you can successfully delete the stack and then manually address the retained resource as needed.

To route traffic based on the URL path during a transition period where both an EC2-based legacy application and a new AWS Lambda function are in use:

Use of Application Load Balancer (ALB): ALBs support advanced request routing based on the URL path, among other criteria. This capability allows the ALB to evaluate the URL path of incoming requests and route them appropriately to either the legacy EC2 instances or the Lambda function.

Path-Based Routing Rules: Configure the ALB with rules that specify which URL paths should be directed to the EC2 instances and which should be routed to the Lambda function. For example, requests to /legacy/* might go to the EC2 instances, while /new/* could be directed to the Lambda function.

Integration with Lambda: ALBs can directly invoke Lambda functions in response to HTTP requests, making them ideal for scenarios where both server-based and serverless components are used in tandem.

This setup not only facilitates a smooth transition by enabling simultaneous operation of both components but also leverages the native capabilities of ALBs to manage traffic based on application requirements effectively.

Amazon RDS Proxy is a fully managed, highly available database proxy for Amazon RDS that helps improve the scalability, availability, and security of database applications. It allows applications to pool and share database connections, reducing the overhead associated with opening and closing connections, which can be particularly beneficial in scenarios with fluctuating workloads, such as those managed by Auto Scaling groups.

By implementing RDS Proxy, you can:

Reduce CPU and Memory Overhead:By managing a pool of connections, RDS Proxy reduces the number of active connections to the database, thereby decreasing the CPU and memory usage on the RDS instance.

Improve Application Scalability:RDS Proxy can handle a large number of simultaneous connections, making it easier to scale applications without overloading the database.

Enhance Availability:In the event of a database failover, RDS Proxy can automatically connect to a standby database instance, preserving application connections and reducing failover times.

Therefore, creating an RDS Proxy and configuring it to connect to the existing PostgreSQL database is the most effective solution to meet the company's requirements.

HTTP 502 errors from CloudFront can occur because of the following reasons:

There's an SSL negotiation failure because the origin is using SSL/TLS protocols and ciphers that aren't supported by CloudFront.

There's an SSL negotiation failure because the SSL certificate on the origin is expired or invalid, or because the certificate chain is invalid.

There's a host header mismatch in the SSL negotiation between your CloudFront distribution and the custom origin.

The custom origin isn't responding on the ports specified in the origin settings of the CloudFront distribution.

The custom origin is ending the connection to CloudFront too quickly.

https://aws.amazon.com/premiumsupport/knowledge-center/resolve-cloudfront-connection-error/

Understand the Problem:

The requirement is to delete the CloudFormation stack without deleting the DynamoDB table.

Analyze the Requirements:

Ensure the DynamoDB table is preserved when the CloudFormation stack is deleted.

Evaluate the Options:

Option A: Add a Retain deletion policy to the DynamoDB resource.

The Retain policy ensures that the DynamoDB table is not deleted when the stack is deleted.

Option B: Add a Snapshot deletion policy to the DynamoDB resource.

Snapshot policy is not applicable to DynamoDB tables and would not retain the table itself.

Option C: Enable termination protection on the CloudFormation stack.

Prevents stack deletion entirely but does not specifically protect the DynamoDB table.

Option D: Update the IAM policy with a Deny statement for dynamodb:DeleteTable.

Prevents deletion of the table but is not a CloudFormation stack-specific solution.

Select the Best Solution:

Option A: Adding a Retain deletion policy to the DynamoDB resource in the CloudFormation stack ensures the table is preserved when the stack is deleted.

AWS CloudFormation Deletion Policy

Using the Retain deletion policy ensures that the DynamoDB table is not deleted when the CloudFormation stack is deleted, preserving critical data.

Based on the attached policy, the following actions are allowed for the IAM user:

Allow Amazon RDS DescribeDBInstances Action:

The policy allows rds:Describe* actions on all resources without any condition, so the user can describe RDS instances in any region.

Example action:

rds:DescribeDBInstances

The connectivity issues could be due to:

Security Group Ingress Rules:

Ensure that the security group for the RDS database has the correct ingress rules allowing traffic from the web server’s security group or IP address.

Go to the RDS console, select your database instance, and check the security groups.

In the security group settings, verify that the correct port (usually 3306 for MySQL) is open for the web server's IP or security group.

Port Configuration:

Verify that the application is configured to use the correct port that matches the RDS database configuration.

Check the application configuration files to ensure the port number matches the port specified in the RDS instance.

Amazon RDS Security Groups

Troubleshooting RDS Connectivity

To minimize cost while maintaining immediate retrievability for files stored in Amazon S3, you can use S3 Lifecycle policies to transition objects to different storage classes based on their access patterns. Given that files are frequently accessed in the first 30 days and rarely accessed afterward, transitioning to S3 Standard-IA after 30 days is the most cost-effective solution.

Understand S3 Storage Classes:

S3 Standard: Suitable for frequently accessed data.

S3 Standard-Infrequent Access (S3 Standard-IA): Suitable for data that is less frequently accessed but requires rapid access when needed. It offers lower storage costs compared to S3 Standard but has a retrieval fee.

S3 One Zone-Infrequent Access (S3 One Zone-IA): Similar to S3 Standard-IA but stores data in a single Availability Zone, making it less resilient.

S3 Glacier: Suitable for archival storage where data retrieval time is not critical (minutes to hours).

Requirements and Solution:

Access Pattern: Frequent access in the first 30 days, rare access afterward.

Retrievability: Immediate access required for one year.

Cost Efficiency: Minimize storage costs after the first 30 days.

Implementing Lifecycle Policy:

Lifecycle Policy: Configure a lifecycle policy to transition objects to S3 Standard-IA after 30 days.

Step-by-Step Implementation:

Login to AWS Management Console:

Open the Amazon S3 console at Amazon S3 Console.

Navigate to the Bucket:

Select the bucket where the files are stored.

Configure Lifecycle Policy:

Go to the Management tab.

Choose Lifecycle and then + Add lifecycle rule.

Enter a rule name and scope (e.g., apply to all objects in the bucket or specific prefixes).

Under Lifecycle rule actions, choose Transition current versions of objects between storage classes.

Add a transition:

Days after object creation: 30

Storage class: S3 Standard-IA

Optionally, add expiration actions if objects should be deleted after a certain period.

Review and Save:

Review the configuration and save the lifecycle rule.

Amazon S3 Storage Classes

Lifecycle Configuration Elements

Transitioning Objects Using Amazon S3 Lifecycle

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

To minimize costs while moving from EC2 instances to AWS Fargate, Compute Savings Plans are the most flexible and cost-effective option. Compute Savings Plans apply to a variety of compute services including AWS Fargate, Amazon EC2, and AWS Lambda, allowing for greater flexibility in managing costs as the company transitions to using only Fargate.

Compute Savings Plans:

Savings Plans provide significant savings over On-Demand pricing, up to 66% savings.

Compute Savings Plans offer the flexibility to move across instance types, AWS Regions, and operating systems.

Payment Options:

The No Upfront payment option provides the most flexibility and avoids large upfront capital expenditures.

The Partial Upfront payment option offers more savings but requires an initial payment.

1-Year Term:

A 1-year term is suitable for the company's 6-month transition period, allowing for cost savings without a long-term commitment.

AWS Savings Plans

Compute Savings Plans

https://docs.aws.amazon.com/efs/latest/ug/encryption.html

Amazon EFS supports two forms of encryption for file systems, encryption of data in transit and encryption at rest. You can enable encryption of data at rest when creating an Amazon EFS file system. You can enable encryption of data in transit when you mount the file system.

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.

You can create an Amazon CloudWatch alarm that monitors an Amazon EC2 instance and automatically recovers the instance if it becomes impaired due to an underlying hardware failure or a problem that requires AWS involvement to repair. Terminated instances cannot be recovered. A recovered instance is identical to the original instance, including the instance ID, private IP addresses, Elastic IP addresses, and all instance metadata. If the impaired instance has a public IPv4 address, the instance retains the public IPv4 address after recovery. If the impaired instance is in a placement group, the recovered instance runs in the placement group. When the StatusCheckFailed_System alarm is triggered, and the recover action is initiated, you will be notified by the Amazon SNS topic that you selected when you created the alarm and associated the recover action. https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-recover.html

Specifying the capacity-optimized allocation strategy for Spot Instances and adding more instance types to the Auto Scaling group is the best action to meet the requirements. Increasing the size of the instances in the Auto Scaling group will not necessarily help with the launch time or reduce interruptions, as the Spot Instances could still be interrupted even with larger instance sizes.

You are correct that an A record typically points to an IP address. However, in the case of an Application Load Balancer (ALB), you cannot use an A record with an IP address because the IP addresses of an ALB can change over time. Instead, you can use an alias record to point to the DNS name of the ALB. An alias record is a Route 53 extension to DNS that allows you to route traffic to selected AWS resources, such as an ALB, by using a friendly DNS name, such as example.com, instead of the resource’s IP address or DNS name.

The company wants to:

Distribute traffic across two AWS Regions

Minimize response time

From the Route 53 Routing Policies Documentation:

Latency-based routing allows you to route traffic to the AWS Region that provides the lowest latency for the user.

Ideal for applications deployed in multiple AWS Regions.

This matches the scenario exactly.

For a disaster recovery (DR) plan with a 15-minute RTO and RPO, the most cost-effective steps include:

B: Configuring the Aurora cluster to replicate data to the DR region using the Aurora global database option. This allows continuous replication with typically low replication lag, meeting the 15-minute RPO requirement efficiently.

C: Pre-configuring the DR region with an ALB and an Auto Scaling group using the same configuration as the primary region. This ensures readiness and quick failover, aligning with the 15-minute RTO target.

These steps provide a robust disaster recovery setup that minimizes downtime and data loss while optimizing costs by using built-in AWS functionalities and avoiding over-provisioning. More information can be found in the AWS documentation on Aurora Global Databases Aurora Global Databases and disaster recovery planning AWS Disaster Recovery.

To make an internal web application highly available, you should configure the Amazon EC2 Auto Scaling group to launch instances in multiple Availability Zones within the same AWS Region. This ensures that the application remains available even if one Availability Zone becomes unavailable.

Login to AWS Management Console:

Open the Amazon EC2 console at Amazon EC2 Console.

Update Auto Scaling Group:

In the navigation pane, choose Auto Scaling Groups.

Select the Auto Scaling group that you want to modify.

Choose Edit.

Add Multiple Availability Zones:

In the Availability Zones and subnets section, select at least one additional Availability Zone.

Ensure that the selected subnets belong to different Availability Zones.

Save Changes:

Save the configuration changes to update the Auto Scaling group.

Distributing Instances Across Multiple Availability Zones

Auto Scaling Groups

Problem Analysis:

The Cache-Control header (max-age=1 hour) conflicts with the CloudFront Maximum TTL setting (5 minutes).

CloudFront adheres to the lower of the two settings, leading to assets being cached for only 5 minutes.

Understanding Cache Behavior in CloudFront:

CloudFront evaluates headers such as Cache-Control and Expires along with its TTL settings.

The effective cache duration is the minimum value among these settings.

Resolution:

Align the Cache-Control max-age header and CloudFront Maximum TTL settings:

Update the CloudFront behavior to use a consistent value (e.g., set both to 1 hour).

Why Other Options Are Incorrect:

A: The Expires header value is irrelevant as CloudFront primarily considers Cache-Control and TTL settings.

B: The issue is not about expiring cached assets but about the duration of cache retention.

C: Cache invalidation is not required as it addresses purging specific objects from cache.

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

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/