Free MuleSoft MCIA-Level-1 Practice Exam with Questions & Answers | Set: 2

When a Mule application using VM (Virtual Machine) queues is deployed to a customer-hosted cluster or multiple CloudHub workers, the messages are consumed by the Mule engine in a non-deterministic way. Here’s an in-depth explanation:

• VM Queues Overview:
• Deployment in Clusters or Multiple Workers:
• Non-Deterministic Message Consumption:
• Advantages:
• Considerations:

References:

• MuleSoft Documentation on VM Connector
• MuleSoft Documentation on High Availability Clustering
• MuleSoft Documentation on Deploying to CloudHub

• JMS (Java Message Service): JMS is a robust messaging standard that supports reliable and asynchronous communication. It allows message producers and consumers to exchange messages via a common message broker.
• Transactions with Automatic Acknowledgements: Utilizing JMS transactions ensures that messages are processed reliably. The automatic acknowledgement mode means that once the consumer receives the message, it acknowledges the broker automatically, ensuring that no messages are lost.
• Performance and Reliability: JMS transactions offer both high performance and reliability. By enabling transactions, each message processing step can be committed or rolled back, ensuring data integrity.
• Cross-Cluster Messaging: For a stock trading company dealing with millions of trades, using JMS transactions allows for consistent and reliable message delivery across different clusters in their network. This approach is more suitable compared to non-transactional or VM queues due to the scale and reliability requirements.
• Event-Driven APIs: The APIs can leverage the transactional nature of JMS to ensure that messages exchanged between different services are reliable and can recover gracefully from failures.

References:

• MuleSoft Documentation on JMS Connector: MuleSoft JMS Connector
• JMS 2.0 Specification: Oracle JMS 2.0

When multiple Mule applications need to listen on the same port (e.g., port 443), configuring them individually will cause a conflict because only one application can bind to a specific port on a server at a time. To resolve this, you can use a Mule domain project, which allows multiple Mule applications to share configurations, including HTTP listeners. Here’s how you can do it:

• Create a Mule Domain Project:
• Configure the Shared HTTP Listener:

<http:listener-config name="Shared_HTTPS_Listener" doc:name="HTTP Listener Configuration" > <http:listener-connection host="0.0.0.0" port="443"/> </http:listener-config>

• Reference the Shared HTTP Listener in Mule Applications:

<http:listener-config name="Shared_HTTPS_Listener" doc:name="HTTP Listener Configuration" > <http:listener-connection host="0.0.0.0" port="443" domain="my-domain-project"/> </http:listener-config>

• Deploy the Domain Project and Applications:

By using a domain project to centralize the HTTP listener configuration, you ensure that both APIs can listen on port 443 without conflicts, allowing customers to access both APIs through the same port.

References

• MuleSoft Documentation: Domain Projects
• MuleSoft Documentation: HTTP Listener Configuration

To close the IT delivery gap, MuleSoft recommends that IT organizations make their technology assets easily discoverable via a central repository. This approach ensures that existing assets, such as APIs, connectors, templates, and other reusable components, are accessible to all teams within the organization. By having a central repository, teams can quickly find and leverage these assets, reducing duplication of effort, speeding up project delivery, and fostering a culture of reuse and collaboration. This strategy aligns with the principles of an API-led connectivity approach, where reusable assets and APIs form the foundation for scalable and efficient IT delivery.

References

• MuleSoft Documentation on API-led Connectivity
• Anypoint Platform Best Practices for Asset Management

MuleSoft's API development best practices emphasize a design-first approach, which starts with writing and approving an API contract before any implementation begins. This approach ensures that the API's interface is agreed upon and understood by all stakeholders before the backend is built. It involves creating an API specification using tools like RAML or OpenAPI, which serves as a blueprint for development. This method promotes better planning, communication, and alignment between different teams and stakeholders, leading to more efficient and predictable API development processes.

References:

• API Design Best Practices
• MuleSoft's Approach to API Development

Set the Anypoint MQ connector operation to publish or consume messages, or to accept (ACK) or not accept (NACK) a message.

When a batch job instance running on a runtime fabric environment with two cluster replicas encounters an unexpected failure, the following sequence of events occurs:

• Failure Detection: The runtime fabric environment detects the failure of the replica running the batch job.
• Replica Replacement: A new replica is provisioned to replace the failed one.
• Batch Job State Recovery: MuleSoft’s batch processing mechanism ensures that the state of the batch job is periodically saved (checkpointing). This allows the new replica to resume processing from the last saved state.
• Resumption of Processing: The new replica takes over the batch job, continuing from where the previous one left off, thus processing the remaining 99,000 records without starting from scratch or causing duplicate processing.

References:

• MuleSoft Documentation on Batch Processing
• Runtime Fabric Guide

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Explanation

We need to note few things about the scenario which will help us in reaching the correct solution.

Point 1 : The APIs are all publicly available and are associated with several mobile applications and web applications. This means Apply an IP blacklist policy is not viable option. as blacklisting IPs is limited to partial web traffic. It can't be useful for traffic from mobile application

Point 2 : The organization does NOT want to use any authentication or compliance policies for these APIs. This means we can not apply HTTPS mutual authentication scheme.

Header injection or removal will not help the purpose.

By its nature, JSON is vulnerable to JavaScript injection. When you parse the JSON object, the malicious code inflicts its damages. An inordinate increase in the size and depth of the JSON payload can indicate injection. Applying the JSON threat protection policy can limit the size of your JSON payload and thwart recursive additions to the JSON hierarchy.

Hence correct answer is Apply a JSON threat protection policy to all APIs to detect potential threat vectors

• Timeout Attribute:
• Transaction Management:
• Implications of Timeout:

References:

• MuleSoft Documentation on JMS Connector
• Understanding XA Transactions