Kafka Simulator: Producers, Partitions and Consumer Groups
Send events with a key, watch them land in partitions, and let consumer groups read at their own speed. A hands-on Kafka simulator in your browser.
Kafka basics: common questions
What is a Kafka consumer group?
A set of consumers that share a topic's partitions. Each partition is read by exactly one consumer in the group, and each group keeps its own offsets, so different groups each get every event.
Does reading a message delete it in Kafka?
No. Messages stay until the topic's retention time or size limit removes them. Consumers only move their own offset forward.
What is an offset in Kafka?
The position of a record inside one partition. A consumer group stores the next offset it will read for every partition.
More on the Kafka course
- How Uber, Netflix and Zomato Use Kafka: Real Architectures
- Kafka Interview Questions: 26 Real Production Problems
- Kafka vs a Message Queue: Why Events Stay After Reading
- Kafka Topics vs Partitions and Message Keys Explained
- Kafka Producer Batching: Async Send, linger.ms, batch.size
- Event-Driven Architecture with Kafka: Drop Sync Calls
- Kafka Fan-Out: One Event, Many Consumer Groups
- Transactional Outbox Pattern with Kafka Explained
- Kafka acks=all and min.insync.replicas Explained
- Idempotent Kafka Consumers: Handle Duplicate Events
- Kafka Outbox Duplicates: Dedupe by Event ID, Not Offset
- Kafka Message Ordering: Global vs Per-Key Order
- Kafka Hot Partition: Choosing the Right Message Key
- Kafka Consumer Lag: More Consumers Than Partitions
- Kafka Retry and Dead Letter Queue (DLQ) Pattern
- Kafka Log Compaction Explained: Latest Value per Key
- Event Sourcing with Kafka: Keep Every Change
- Kafka Schema Evolution and Schema Registry Explained
- Kafka Exactly-Once Semantics: Where It Ends
- Kafka Share Groups (Queues for Kafka) Explained
- Kafka Consumer Group Rebalancing Without Pauses
- Kafka Rack Awareness: Replicas Across Zones
- Kafka max.poll.interval.ms: Slow Consumers Kicked Out
- Kafka Monitoring: Alert on Lag Time, Not Message Count
- Kafka Quotas: Stop a Replay Hurting Live Traffic
- Kafka Security: TLS, SASL and ACLs Explained
- Kafka Tiered Storage Explained
- Kafka Multi-Region and Disaster Recovery
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