Microsoft Certified: Azure Developer Associate Advanced Practice Exam: Hard Questions 2025

You maintain an HTTP-triggered Azure Function that processes image uploads and writes metadata to Cosmos DB. Under load tests, you notice sporadic duplicate metadata documents for the same upload. The client sometimes retries requests due to timeouts, and the function occasionally runs longer than the client timeout. You must guarantee idempotent writes without introducing a server-side distributed lock and without reducing throughput. What should you do?

You run a containerized background processor on Azure Container Apps. It consumes messages from an Azure Service Bus queue and performs CPU-intensive transformations that may take up to 8 minutes per message. During scale-out, you observe duplicate processing when a container instance crashes mid-work, and occasionally messages are abandoned and retried even though work completed. You need at-least-once delivery with minimized duplicates and correct completion semantics. What should you implement?

An ASP.NET Core API hosted on Azure App Service must call a downstream internal API protected by Azure AD. The API is experiencing intermittent 401 responses only after running for several hours, and the failures disappear after restarting the App Service. You suspect access tokens are being cached incorrectly. You want a resilient approach that avoids token expiry issues and supports scale-out. What should you do?

You have an event-driven pipeline: Blob upload triggers an Event Grid event, which is routed to an Azure Function that enqueues work to Service Bus. You must ensure that if the Function fails after enqueuing, the event is not processed again in a way that causes duplicate Service Bus messages. You cannot use a database transaction across Event Grid and Service Bus. What is the best approach?

A .NET worker reads from an Azure Storage queue and writes results to Azure Table storage. Occasionally, processing takes longer and messages are processed twice by different instances. You already increased visibility timeout, but duplicates still occur when instances crash. You need to make the operation safe without central coordination. What should you do?

A high-throughput API uses Azure Cosmos DB (Core SQL) and must support point reads by id and partition key with low RU consumption. Developers report unexpectedly high RU charges and occasional 429 responses. Investigation shows the code often queries by a non-partitioned property and then filters client-side. You must reduce RU usage and minimize throttling without changing the logical requirements. What should you do?

Your team stores sensitive configuration values (API keys, connection strings) in Azure Key Vault. An Azure Function must read secrets at runtime. Security requires that no secrets are stored in code or app settings, and access must be limited to only the necessary secrets. You also need to minimize Key Vault throttling under bursty traffic. What should you do?

A microservice running on Azure App Service calls several downstream services and emits custom telemetry to Application Insights. During incidents, you need to correlate a single user request across the inbound HTTP call, the outgoing HTTP calls, and an asynchronous message sent to Service Bus. Today, traces are fragmented across different operation IDs. What should you implement?

You deploy a new version of an Azure Function app. After deployment, you see intermittent failures where some invocations use old configuration values and others use new ones. The app uses deployment slots and swaps for zero downtime. You must ensure configuration consistency during swaps and avoid partial configuration updates across instances. What should you do?

Your API is protected by Azure AD and exposed through Azure API Management (APIM). A partner must call the API using OAuth 2.0, but they cannot use user-interactive flows. The partner’s client must be restricted to a subset of operations, and tokens must be validated consistently even if the backend changes. What is the best design?