Amazon Web Services Updated SOA-C02 Exam Questions and Answers by asa

To restrict access to an Amazon S3 bucket to Amazon EC2 instances in a VPC only, and ensure all traffic is over the AWS private network, the SysOps administrator should create a VPC endpoint for the S3 bucket and create an S3 bucket policy that conditionally limits all S3 actions on the bucket to the VPC endpoint as the source.

Create a VPC Endpoint for S3:

Open the VPC console.

Choose "Endpoints" and then "Create Endpoint."

Select the service name "com.amazonaws.[region].s3."

Choose the VPC and the subnets where the EC2 instances reside.

Configure the route tables to include the VPC endpoint.

Create an S3 Bucket Policy:

Open the S3 console and select the bucket.

Go to the "Permissions" tab and edit the bucket policy.

Add a condition to the policy to allow access only from the VPC endpoint.

Example policy:

{

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

"Statement": [

{

"Effect": "Allow",

"Principal": "*",

"Action": "s3:*",

"Resource": [

"arn:aws:s3:::your-bucket-name",

"arn:aws:s3:::your-bucket-name/*"

],

"Condition": {

"StringEquals": {

"aws:sourceVpce": "vpce-12345678"

}

}

}

]

}

References:

Amazon S3 VPC Endpoints

Amazon S3 Bucket Policies

Amazon CloudWatch Logs Insights allows you to interactively search and analyze your log data. This can be used to quickly identify the top internet destinations accessed by the EC2 instances.

Steps:

Open CloudWatch Logs Insights:

Open the Amazon CloudWatch console.

In the navigation pane, choose "Logs Insights".

Select the Log Group:

Select the log group that contains the VPC flow logs for the NAT gateway.

Run a Query:

Use the following query to identify the top five internet destinations:

sql

Copy code

fields @timestamp, dstAddr

| stats count(*) as requestCount by dstAddr

| sort requestCount desc

| limit 5

This query will count the number of requests to each destination address, sort them in descending order, and limit the results to the top five.

Analyze Results:

Review the output to identify the top five internet destinations that the EC2 instances communicate with for downloads.

References:

CloudWatch Logs Insights

Analyzing VPC Flow Logs with CloudWatch Logs Insights

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.

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.