SOA-C02 Exam Dumps - Amazon Web Services AWS Certified Associate Questions and Answers

To reconfigure the infrastructure to support a microservices approach with the least administrative overhead, using an Application Load Balancer (ALB) with path-based routing is the most suitable solution.

Application Load Balancer (ALB):

ALBs are designed to distribute incoming application traffic across multiple targets, such as EC2 instances, in one or more Availability Zones.

ALBs support path-based routing, which allows you to route requests to different microservices based on the URL path.

Path-Based Routing:

With path-based routing, you can configure your ALB to route requests to specific target groups based on the URL path.

For example, requests to example.com/service1/* can be routed to one microservice, while requests to example.com/service2/* can be routed to another.

Implementation Steps:

Go to the EC2 console and navigate to "Load Balancers."

Create an ALB and configure the listener.

Define rules for path-based routing and create target groups for each microservice.

Register the appropriate EC2 instances with each target group.

Application Load Balancers

ALB Path-Based Routing

To increase the cache hit ratio for an Amazon CloudFront distribution, you can make several adjustments to its configuration:

Minimize Forwarding of Cookies, Query Strings, and Headers:

By default, CloudFront caches based on URL, but if it forwards headers, cookies, and query strings to the origin, it can decrease the cache hit ratio.

Navigate to your CloudFront distribution in the AWS Management Console.

In the Behaviors tab, edit the cache behavior.

Set the option to forward only the necessary cookies, query strings, and headers. This reduces the variations of objects stored in the cache.

Increase Time to Live (TTL) Settings:

Increasing the TTL allows objects to stay in the cache for a longer period, reducing the frequency of fetching data from the origin.

In the same Behaviors tab, adjust the Minimum TTL, Maximum TTL, and Default TTL settings to higher values. This ensures that content remains cached for a longer duration before it needs to be fetched again from the origin.

Cache Behavior Settings

Optimizing Cache Behavior

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

Objective:

Notify administrators via email whenever a root user sign-in event occurs.

Using Amazon EventBridge and Amazon SNS:

EventBridge: Captures the root user sign-in events from AWS CloudTrail.

SNS: Publishes email notifications to subscribed recipients.

Steps to Implement:

Step 1: Enable CloudTrail for management events if not already enabled.

Step 2: Create an EventBridge rule:

Event pattern:

{

"source": ["aws.signin"],

"detail-type": ["AWS Console Sign In via Root Account"]

}

Step 3: Set the rule target to an SNS topic.

Step 4: Subscribe email addresses to the SNS topic.

AWS References:

EventBridge Rules:Creating EventBridge Rules

SNS Subscriptions:Amazon SNS Subscriptions

Why Other Options Are Incorrect:

Option A: Trusted Advisor does not directly send notifications for root sign-ins.

Option B: Using an EC2 instance and scripts is less efficient and not operationally optimized.

Option C: Sending notifications to SQS introduces unnecessary complexity and delays.

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.

NAT Gateway resides in public subnet, and traffic should be routed from private subnet to NAT Gateway: https://docs.aws.amazon.com/vpc/latest/userguide/vpc-nat-gateway.html

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

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 ensure that the application running on an Amazon EC2 instance can read, write, and delete messages from the SQS queues in the most secure manner, the recommended approach is to use IAM roles for EC2 instances. This approach avoids the need to embed or export long-term AWS credentials, which can be a security risk.

Create an IAM Role for EC2:

Navigate to the IAM console in the AWS Management Console.

Choose "Roles" in the navigation pane, then click "Create role".

Select "AWS service" as the type of trusted entity and choose "EC2" as the use case. Click "Next: Permissions".

Attach the Required Permissions:

On the "Attach permissions policies" page, you can either select an existing policy or create a custom policy.

For a custom policy, click "Create policy" and use the following JSON policy to allow the required SQS actions:

json

Copy code

{

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

"Statement": [

{

"Effect": "Allow",

"Action": [

"sqs:SendMessage",

"sqs:ReceiveMessage",

"sqs:DeleteMessage"

],

"Resource": "arn:aws:sqs:region:account-id:queue-name"

}

]

}

Replace region, account-id, and queue-name with appropriate values for your SQS queues.

Assign the Role to the EC2 Instance:

After creating the role with the necessary permissions, navigate to the EC2 console.

Select the instance that needs access to the SQS queues.

In the "Actions" menu, choose "Security", then "Modify IAM role".

Attach the newly created IAM role to the instance.

Verify the Permissions:

Ensure that the IAM role is properly attached to the EC2 instance.

Test the application to confirm that it can successfully perform the required actions (read, write, delete) on the SQS queues.

IAM Roles for Amazon EC2

Amazon SQS Policy Examples

To receive an email notification based on a metric threshold, use:

A CloudWatch alarm monitoring FreeStorageCapacity

A CloudWatch alarm action that publishes to an SNS topic

From the CloudWatch Alarm and SNS Documentation:

You can create an alarm on a metric (e.g., FreeStorageCapacity) and configure the alarm action to send a notification to an Amazon SNS topic, which triggers an email notification to all subscribed endpoints.