MuleSoft-Platform-Architect-I Exam Dumps : Salesforce Certified MuleSoft Platform Architect (Mule-Arch-201)

Understanding Circuit Breaker Policy:

A circuit breaker is a design pattern used to detect failures and prevent an application from continually trying to execute a failing operation. In this case, it will help improve response time and reduce demand on the downstream API.

The specified configuration includes conditions for opening, half-opening, and closing the circuit based on error rates over time:

Circuit Open: Triggered if there are more than 10 errors per minute for three consecutive minutes.

Circuit Half-Open: The circuit transitions to half-open if there is one error per minute.

Circuit Closed: The circuit closes if the error rate is less than one error per minute for five minutes.

Evaluating the Options:

Option A: Creating a custom policy with template expressions could work, but it would require custom development. Since the Anypoint Platform already has a Circuit Breaker policy available, this would be a less efficient and more complex solution.

Option B: Anypoint Monitoring alerts can be used for monitoring the API, but they do not provide circuit-breaking functionality. Additionally, implementing a retry strategy for the half-open state is not sufficient to achieve the required circuit breaker behavior.

Option C (Correct Answer): Adding the Circuit Breaker policy to the API instance on Anypoint Platform allows you to set up circuit-breaking conditions directly. This approach uses the built-in Circuit Breaker policy, where you can configure parameters such as error thresholds and time intervals to match the requirements. This solution is efficient, reliable, and leverages Anypoint’s out-of-the-box capabilities.

Option D: Implementing the strategy within a Mule application with a YAML configuration could be complex and less manageable. Additionally, it does not leverage Anypoint Platform’s built-in Circuit Breaker policy, which is more suited to this scenario.

Conclusion:

Option C is the correct choice, as it leverages Anypoint Platform’s Circuit Breaker policy. This solution allows for configuring thresholds and time intervals as specified, improving response time and reducing demand on the downstream API while utilizing Anypoint's managed policy feature.

Refer to MuleSoft’s documentation on implementing the Circuit Breaker policy in API Manager for detailed configuration guidance.

In a CloudHub deployment with a single worker/replica located in a specific Availability Zone (AZ), if an AZ experiences an outage, here’s what happens:

Worker Availability: Since the application is deployed in a single AZ, CloudHub does not automatically redeploy the application in a different zone or region during an outage. Thus, if the current AZ is unavailable, the application will be offline.

Auto-Restart upon AZ Recovery: Once the affected AZ is back online, CloudHub will auto-restart the worker in the same AZ without manual intervention. This ensures that as soon as the AZ is functional, the application resumes automatically.

Explanation of Correct Answer (B):

Option B accurately describes the situation, as the API will remain unavailable until the original AZ is restored.

CloudHub does not currently support automatic failover across regions or other availability zones within the same region for single-worker deployments on the shared cloud.

Explanation of Incorrect Options:

Option A (auto-redeployment in the U.S. East region) is incorrect, as CloudHub does not migrate across regions automatically.

Option C (redeployment in another AZ within the U.S. West) is not a feature for single-worker deployments.

Option D (manual redeployment triggered by an admin) is unnecessary as CloudHub handles restarts automatically when the AZ is back online.

ReferencesRefer to MuleSoft CloudHub’s availability and disaster recovery documentation for more information on how CloudHub manages availability in shared environments​.

Understanding the Requirements:

Business Groups: The solution must support two business groups, which typically require separate VPCs for logical separation.

High Availability (HA): Requires deploying resources across multiple availability zones.

Dedicated Load Balancer (DLB): Traffic should be routed via DLBs, which operate within VPCs on CloudHub.

Separate Environments: There needs to be separation between production and non-production environments.

Evaluating the Options:

Option A: Using a single production and non-production VPC and differentiating business groups via availability zones is not ideal as it does not provide full separation for each business group, and using maximum CIDR allocation is wasteful.

Option B (Correct Answer): Creating separate production and non-production VPCs per business group with minimized CIDR blocks, multiple availability zones, and multiple workers per application for HA meets all requirements effectively.

Option C: While this option separates VPCs per business group, it does not fully address the requirement for HA across availability zones by specifying multi-zone deployment only during API deployment, which may not guarantee redundancy.

Option D: Configuring subnets to differentiate business groups within a single production and non-production VPC does not fully separate the business groups, which is a requirement.

Conclusion:

Option B is the best choice as it meets the requirements for high availability, business group separation, and cost efficiency by using minimized CIDR allocations and deploying multiple workers across availability zones.

For further reference, refer to MuleSoft's documentation on VPC configuration and high availability deployment strategies.