Configuring Azure Event Hubs for Developers

Configuring Azure Event Hubs

This section covers essential configuration options for Azure Event Hubs that developers need to be aware of when building event-driven applications. Understanding these settings is crucial for performance, scalability, and cost-effectiveness.

Namespace and Event Hub Creation

Event Hubs are organized within a namespace. When creating an Event Hub, you'll typically specify:

Name: A unique identifier for your Event Hub.
Partition Count: Determines the number of parallel streams for ingress and egress. Higher partition counts allow for greater throughput but can increase complexity.
Message Retention: The duration for which event data is retained. This can be set in hours or days.

Throughput Units (TUs) / Processing Units (PUs)

Event Hubs capacity is managed through Throughput Units (TUs) for Standard tier or Processing Units (PUs) for Premium tier. These units define the maximum ingress and egress bandwidth for your Event Hub namespace.

Standard Tier (TUs): You can manually scale TUs or enable Auto-Inflate to automatically increase TUs up to a specified maximum.
Premium Tier (PUs): Offers dedicated resources and more predictable performance. PUs are allocated per namespace.

Important: Carefully consider your expected message volume and processing needs when choosing TUs or PUs. Over-provisioning can lead to unnecessary costs, while under-provisioning can cause throttling and performance issues.

Partitioning Strategy

The number of partitions is a critical configuration that impacts scalability and ordering guarantees. Events sent to a specific partition key will always land in the same partition. This is essential for maintaining order within a logical stream of events.

Choose the partition count based on your expected throughput and the number of consumers that will be reading in parallel.
The maximum number of partitions is dependent on the Event Hubs tier and the total number of TUs/PUs in the namespace.

Message Retention Policies

Configure how long event data is stored within an Event Hub. This is important for compliance, debugging, and replaying events.

Time-based retention: Data is deleted after a specified period (e.g., 24 hours, 7 days).
Capture: Configure Event Hubs Capture to automatically archive events to Azure Blob Storage or Azure Data Lake Storage. This is ideal for long-term archival and batch processing scenarios.


{
  "name": "my-data-stream",
  "partitionCount": 12,
  "messageRetentionInHours": 48,
  "captureEnabled": true,
  "captureIntervalInSeconds": 300,
  "captureSizeLimitInMB": 100,
  "captureStorageAccount": "your-storage-account-name",
  "captureBlobContainer": "eventhubs-archive"
}

Consumer Groups

Consumer groups allow multiple applications or services to independently read from an Event Hub without interfering with each other. Each consumer group maintains its own offset, meaning consumers within different groups can start reading from different points in the event stream.

Tip: Create a dedicated consumer group for each application or microservice that needs to process events from the Event Hub.

Schema Registry Integration

For robust event handling, consider integrating with a Schema Registry (like Azure Schema Registry) to manage and validate event schemas. This ensures data consistency and facilitates schema evolution.

Regional Deployment and Availability Zones

Deploy your Event Hubs namespace in a region that meets your latency and compliance requirements. For enhanced availability, leverage Availability Zones if your region supports them, which provides fault tolerance by distributing your Event Hubs across multiple physical locations within a region.