Azure Event Hubs is Azure's fully managed real-time event streaming service — the Azure equivalent of Amazon Kinesis Data Streams or Apache Kafka. It ingests millions of events per second, buffers them for a configurable retention period, and enables multiple consumer groups to process the same event stream independently. Event Hubs is natively compatible with the Apache Kafka protocol — existing Kafka producers and consumers connect by updating only the broker endpoint, enabling migration from self-managed Kafka to Azure-managed Event Hubs without any code changes.
An Event Hub is the Azure equivalent of a Kafka topic — a named stream of events organised in Event Hubs Namespaces (the capacity and billing unit). Each Event Hub is divided into partitions — the parallelism unit, equivalent to Kafka partitions and Kinesis shards. Partition count is fixed at creation and cannot be changed without recreating the Event Hub. Event Hubs Standard supports up to 32 partitions and 1-day retention. Premium and Dedicated tiers support higher partition counts and retention up to 90 days.