Free Amazon Web Services DOP-C02 Practice Exam with Questions & Answers | Set: 4

To restrict access to CloudFront to a specific IP address range:

Create an AWS WAF IP address set with the corporate office IPs.

Modify the existing WebACL ' s default action to Block (deny all except explicitly allowed).

Add a high-priority rule that allows traffic from the IP address set (the corporate IPs). This way, only requests from the corporate IPs are allowed; all others are blocked. Regex pattern sets are not necessary for IP-based restrictions and add complexity. Setting default action to Allow with exceptions is less secure and more complex to manage.

https://aws.amazon.com/premiumsupport/knowledge-center/monitor-security-group-changes-ec2/

AWS Config has a managed rule called alb-waf-enabled that checks whether AWS WAF is enabled on ALBs. AWS Config supports automatic remediation actions that can be triggered when noncompliance is detected.

By creating a Systems Manager Automation document that adds AWS WAF to the ALB and associating it as the remediation action for the AWS Config rule, the system can automatically detect and remediate any removal of AWS WAF from ALBs without manual intervention.

This is the most operationally efficient and reliable approach to ensure continuous compliance.

Option B lacks automatic remediation. Options C and D rely on drift detection and Lambda, which add complexity and risk downtime during stack replacement.

ALB supports weighted target groups for traffic splitting between versions without DNS-level changes. By attaching multiple target groups (old & beta) to the same ALB listener rule with weights (90/10), partial traffic testing can occur seamlessly. This is the recommended least-change method per Application Load Balancer advanced request routing documentation.

Enabling EKS control plane logs to CloudWatch captures API requests. CloudWatch Container Insights collects node and pod-level performance data with no additional infrastructure. AWS recommends this integrated observability solution for minimal management overhead.

To implement failover for the application to the secondary Region so that HTTP GET requests meet the desired RTO, the DevOps engineer should use the following solution:

Create a new origin on the distribution for the secondary ALB. A CloudFront origin is the source of the content that CloudFront delivers to viewers. By creating a new origin for the secondary ALB, the DevOps engineer can configure CloudFront to route traffic to the secondary Region when the primary Region is unavailable1

Create a new origin group. Set the original ALB as the primary origin. Configure the origin group to fail over for HTTP 5xx status codes. An origin group is a logical grouping of two origins: a primary origin and a secondary origin. By creating an origin group, the DevOps engineer can specify which origin CloudFront should use as a fallback when the primary origin fails. The DevOps engineer can also define which HTTP status codes should trigger a failover from the primary origin to the secondary origin. By setting the original ALB as the primary origin and configuring the origin group to fail over for HTTP 5xx status codes, the DevOps engineer can ensure that CloudFront will switch to the secondary ALB when the primary ALB returns server errors2

Update the default behavior to use the origin group. A behavior is a set of rules that CloudFront applies when it receives requests for specific URLs or file types. The default behavior applies to all requests that do not match any other behaviors. By updating the default behavior to use the origin group, the DevOps engineer can enable failover routing for all requests that are sent to the distribution3

This solution will meet the requirements because it will automate the failover of the application to the secondary Region with zero-second RTO. When CloudFront receives an HTTP GET request, it will first try to route it to the primary ALB in the primary Region. If the primary ALB is healthy and returns a successful response, CloudFront will deliver it to the viewer. If the primary ALB is unhealthy or returns an HTTP 5xx status code, CloudFront will automatically route the request to the secondary ALB in the secondary Region and deliver its response to the viewer.

The other options are not correct because they either do not provide zero-second RTO or do not work as expected. Creating a second CloudFront distribution that has the secondary ALB as the default origin and creating Amazon Route 53 alias records that have a failover policy is not a good option because it will introduce additional latency and complexity to the solution. Route 53 health checks and DNS propagation can take several minutes or longer, which means that viewers might experience delays or errors when accessing the application during a failover event. Creating Amazon Route 53 alias records that have a failover policy and Evaluate Target Health set to Yes for both ALBs and setting the TTL of both records to O is not a valid option because it will not work with CloudFront distributions. Route 53 does not support health checks for alias records that point to CloudFront distributions, so it cannot detect if an ALB behind a distribution is healthy or not. Creating a CloudFront function that detects HTTP 5xx status codes and returns a 307 Temporary Redirect error response to the secondary ALB is not a valid option because it will not provide zero-second RTO. A 307 Temporary Redirect error response tells viewers to retry their requests with a different URL, which means that viewers will have to make an additional request and wait for another response from CloudFront before reaching the secondary ALB.

1: Adding, Editing, and Deleting Origins - Amazon CloudFront

2: Configuring Origin Failover - Amazon CloudFront

3: Creating or Updating a Cache Behavior - Amazon CloudFront

Only the Organizations management account (or roles in that account) can call organizations:CreateAccount directly. When moving the Lambda function to a different (dedicated) account, the correct pattern is to perform cross-account role assumption into a role that resides in the management account and has tightly scoped Organizations permissions.

Option A describes exactly this:

Create an IAM role in the management account with only the required Organizations permissions (for example, organizations:CreateAccount and related read permissions).

Configure the trust policy on that role to allow it to be assumed by the Lambda execution role in the new account.

Update the Lambda code to call sts:AssumeRole into the management-account role before invoking the Organizations API.

This approach ensures that:

The Lambda function can create new accounts, but only via the management account.

The Lambda execution role in the dedicated account has no direct Organizations permissions; it only has permission to assume the specific role.

Option B is incorrect because “delegated administration for Organizations” in the generic sense is not how CreateAccount is exposed; account creation remains a management-account responsibility. Options C and D either misconfigure trust or introduce unnecessary Control Tower complexity. Cross-account assume-role from the dedicated account into the management account is the correct and least-privilege solution.

The problem has two distinct requirements: securely managing rotating external API credentials and encrypting CodeBuild artifacts with a specific KMS key.

For credentials that must be reset each month and are sensitive, AWS Secrets Manager is the appropriate service, not Parameter Store. Secrets Manager provides built-in support for secret rotation, versioning, access control, and auditability. The external API credentials can be updated monthly either manually or via an automated rotation Lambda. CodeBuild can read the secret at build time by assuming an IAM role that allows secretsmanager:GetSecretValue .

To encrypt CodeBuild outputs, the correct pattern is to set the CODEBUILD_KMS_KEY_ID environment variable (or CodeBuild project setting) to the desired KMS key. The CodeBuild IAM service role must be granted kms:Encrypt , kms:Decrypt , and related actions on that KMS key via the key policy or IAM policy. This ensures build artifacts and logs are encrypted using the specified customer managed key.

Option C captures both requirements precisely: store credentials in Secrets Manager and update the KMS key policy for the CodeBuild role , not the CodePipeline role. Options A and B misuse Parameter Store and/or the wrong IAM principal. Option D updates the wrong role and does not connect the KMS key to CodeBuild’s artifact encryption.

The following are the steps that the company can take to change the log level dynamically when the deployment occurs:

Create a script that uses the CodeDeploy environment variable DEPLOYMENT_GROUP_NAME to identify which deployment group the instance is part of.

Use this information to configure the log level settings.

Reference this script as part of the BeforeInstall lifecycle hook in the appspec.yml file.

The DEPLOYMENT_GROUP_NAME environment variable is automatically set by CodeDeploy when the deployment is triggered. This means that the script does not need to call the metadata service or the EC2 API to identify the deployment group.

This solution is the least complex and requires the least management overhead. It also does not require different script versions for each deployment group.

The following are the reasons why the other options are not correct:

Option A is incorrect because it would require tagging the Amazon EC2 instances, which would be a manual and time-consuming process.

Option C is incorrect because it would require creating a custom environment variable for each environment. This would be a complex and error-prone process.

Option D is incorrect because it would use the DEPLOYMENT_GROUP_ID environment variable. However, this variable is not automatically set by CodeDeploy, so the script would need to call the metadata service or the EC2 API to get the deployment group ID. This would add complexity and overhead to the solution.

To implement a more reliable deployment solution, a DevOps engineer should take the following actions:

Create a pipeline in AWS CodePipeline that uses the CodeCommit repository as a source provider. Configure pipeline stages that run the CodeBuild project in parallel to build and test the application. In the pipeline, pass the CodeBuild project output artifact to an AWS CodeDeploy action. This action will improve the deployment reliability by automating the entire process from code commit to deployment, reducing human errors and inconsistencies. By running the build and test stages in parallel, the pipeline can also speed up the delivery time and provide faster feedback. By using CodeDeploy as the deployment action, the pipeline can leverage the features of CodeDeploy, such as traffic shifting, health checks, rollback, and deployment configuration123

Create an AWS CodeDeploy application and a deployment group to deploy the packaged code to the EC2 instances. Configure the ALB for the deployment group. This action will improve the deployment reliability by using CodeDeploy to orchestrate the deployment across multiple EC2 instances behind an ALB. CodeDeploy can perform blue/green deployments or in-place deployments with traffic shifting, which can minimize downtime and reduce risks. CodeDeploy can also monitor the health of the instances during and after the deployment, and automatically roll back if any issues are detected. By configuring the ALB for the deployment group, CodeDeploy can register and deregister instances from the load balancer as needed, ensuring that only healthy instances receive traffic45

The other options are not correct because they do not improve the deployment reliability or follow best practices. Creating separate pipeline stages that run a CodeBuild project to build and then test the application is not a good option because it will increase the pipeline execution time and delay the feedback loop. Creating individual Lambda functions that use CodeDeploy instead of Systems Manager to run build, test, and deploy actions is not a valid option because it will add unnecessary complexity and cost to the solution. Lambda functions are not designed for long-running tasks such as building or deploying applications. Creating an Amazon S3 bucket and modifying the CodeBuild project to store the packages in the S3 bucket instead of in CodeArtifact is not a necessary option because it will not affect the deployment reliability. CodeArtifact is a secure, scalable, and cost-effective package management service that can store and share software packages for application development67

1: What is AWS CodePipeline? - AWS CodePipeline

2: Create a pipeline in AWS CodePipeline - AWS CodePipeline

3: Deploy an application with AWS CodeDeploy - AWS CodePipeline

4: What is AWS CodeDeploy? - AWS CodeDeploy

5: Configure an Application Load Balancer for your blue/green deployments - AWS CodeDeploy

6: What is AWS Lambda? - AWS Lambda

7: What is AWS CodeArtifact? - AWS CodeArtifact