Examkin

Question

Difficulty: HardImplement Azure Event Hubs Solutions

You are developing a C# (.NET) management utility to perform maintenance on an Azure Event Hubs ingestion pipeline. The pipeline uses the `EventProcessorClient` along with an Azure Blob Storage container to store checkpoints and partition ownership leases. To force a partition to be reprocessed from the beginning of the stream, your utility must delete the corresponding checkpoint blob. When the utility attempts to delete the blob, a `RequestFailedException` is thrown with HTTP status code 412412 (Precondition Failed) because an active processor instance holds an active lease on the blob. How should you resolve this issue in your C# code to successfully delete the checkpoint blob?

  1. A
    Delete the blob using the `BlobClient.DeleteAsync` method and specify `DeleteSnapshotsOption.IncludeSnapshots` in the request options.
  2. B
    Configure the utility to authenticate using a user-assigned managed identity instead of a system-assigned managed identity to override the lease.
  3. Instantiate a `BlobLeaseClient` for the target blob, call the `BreakAsync` method to release the active lease, and then delete the blob.Answer
  4. D
    Reconfigure the utility to use a `PartitionReceiver` client to programmatically release the partition checkpoint lock from the Event Hubs service namespace.

Answer

Instantiate a BlobLeaseClient for the target blob, call the BreakAsync method to release the active lease, and then delete the blob.
Breaking the lease on the blob removes the concurrency lock held by the EventProcessorClient. This allows the maintenance utility to delete the checkpoint blob and reset the partition processing offset.

Step-by-Step Solution

1
Identify the target checkpoint blob representing the partition ownership inside the Azure Blob Storage container.
The URI and path to the specific blob representing the partition's checkpoint are determined.
The EventProcessorClient creates a specific blob for each partition to store partition leases and offset metadata.
2
Initialize a BlobLeaseClient referencing the targeted checkpoint blob using the Azure Storage SDK.
A client instance capable of executing lease operations on the blob is created.
Standard BlobClient operations fail on leased blobs unless a lease ID is provided or the lease is broken.
3
Execute the BreakAsync method on the BlobLeaseClient instance.
The lease state changes from leased to broken, which unlocks the blob.
Breaking the lease allows modifications and deletion of the blob without needing the original lease ID.
4
Delete the checkpoint blob using BlobClient.DeleteAsync.
The blob is deleted successfully, forcing the event processor to reprocess the partition from the start.
Deleting the checkpoint blob removes the progress offset marker, prompting the EventProcessorClient to default to the configured starting position.

Key Concept

Azure Event Hubs checkpointing lease management using Azure Blob Storage SDK

Alternative Method

If the utility has access to the active EventProcessorClient lease metadata, it can pass the active lease ID inside the BlobRequestConditions of BlobClient.DeleteAsync instead of breaking the lease.
Estimated Time:2m 30s
Rate this question

Topics

Implement Azure Event Hubs Solutions