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Apache Kafka 3.7: A Single Broker with KRaft

Run Kafka without ZooKeeper using KRaft mode, and create a topic.

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  • Apache Kafka 3.7
  • KRaft
  • OpenJDK 17

Since Kafka 3.3, KRaft mode (Kafka’s own metadata quorum) is production-ready for new clusters, and ZooKeeper is deprecated. This walkthrough runs a single node for learning.

sudo apt install -y openjdk-17-jre-headless
curl -O https://downloads.apache.org/kafka/3.7.0/kafka_2.13-3.7.0.tgz
tar -xzf kafka_2.13-3.7.0.tgz && cd kafka_2.13-3.7.0

KAFKA_CLUSTER_ID=$(bin/kafka-storage.sh random-uuid)
bin/kafka-storage.sh format -t $KAFKA_CLUSTER_ID -c config/kraft/server.properties
bin/kafka-server-start.sh config/kraft/server.properties

In another terminal:

bin/kafka-topics.sh --create --topic orders --partitions 3 --bootstrap-server localhost:9092
bin/kafka-console-producer.sh --topic orders --bootstrap-server localhost:9092
bin/kafka-console-consumer.sh --topic orders --from-beginning --bootstrap-server localhost:9092

Concepts:

  • A topic is split into partitions; order is guaranteed only within a partition.
  • Messages stay for the retention period (7 days by default), not until read.
  • Keys decide the partition, so related messages keep their order.

Apache Kafka 3.8 is expected in July. Production clusters need at least three brokers.