AZ-200 Azure Functions & Serverless Computing 2 — Questions and Answers
Question 1: Which Azure Functions Premium Plan feature ensures at least one function instance is always warm to eliminate cold starts?
- Scale controller
- Pre-warmed instances (Correct answer)
- Elastic scale
- VNet integration
Correct answer: Pre-warmed instances
Pre-warmed instances on the Premium Plan keep at least one instance initialized so the first request does not incur a cold-start delay.
Question 2: When using the Timer trigger in Azure Functions, which expression format is used to define the schedule?
- ISO 8601 interval
- CRON expression (Correct answer)
- Quartz Scheduler format
- RFC 2822 date
Correct answer: CRON expression
Timer triggers use a CRON expression (with an optional sixth field for seconds) to define when the function should fire.
Question 3: In Azure Functions, what is the purpose of the host.json file?
- Define per-function bindings
- Store connection strings for local development
- Configure global settings for the function app host (Correct answer)
- List all functions in the app
Correct answer: Configure global settings for the function app host
host.json contains global configuration options that affect all functions in the app, such as logging levels, retry policies, and extension settings.
Question 4: Which Azure Functions trigger automatically scales based on the number of messages in a queue?
- HTTP trigger
- Blob trigger
- Queue Storage trigger (Correct answer)
- Timer trigger
Correct answer: Queue Storage trigger
The Azure Queue Storage trigger monitors queue depth and scales out function instances automatically when messages accumulate.
Question 5: What is the role of the Durable Functions 'Entity function'?
- Trigger the orchestration workflow
- Store and manage stateful objects identified by an entity ID (Correct answer)
- Send HTTP responses to clients
- Schedule timer-based callbacks
Correct answer: Store and manage stateful objects identified by an entity ID
Entity functions (Durable Entities) define operations that read and write small pieces of state, each identified by a unique entity ID.
Question 6: Which setting in local.settings.json is required to run Azure Functions locally?
- FUNCTIONS_WORKER_RUNTIME (Correct answer)
- WEBSITE_RUN_FROM_PACKAGE
- AzureWebJobsDashboard
- FUNCTIONS_EXTENSION_VERSION
Correct answer: FUNCTIONS_WORKER_RUNTIME
FUNCTIONS_WORKER_RUNTIME specifies the language worker (e.g., dotnet, node, python) and is required for the local runtime to load the correct worker process.
Question 7: Which Azure Functions output binding lets a function publish messages directly to an Azure Event Hub?
- Service Bus output binding
- Event Hub output binding (Correct answer)
- Event Grid output binding
- Notification Hub output binding
Correct answer: Event Hub output binding
The Event Hub output binding allows a function to send one or more events to an Event Hub without writing any Event Hubs SDK code.
AZ-200 Azure Functions & Serverless Computing 2
Which Azure Functions Premium Plan feature ensures at least one function instance is always warm to eliminate cold starts?