A topic's retention time can be configured in Kafka. A topic's default retention time is seven days. While creating a new subject, we can set the retention time. When a topic is generated, the broker's property log.retention.hours are used to set the retention time. When configurations for a currently operating topic need to be modified, kafka-topic.sh must be used.

The right command is determined on the Kafka version in use.

The command to use up to 0.8.2 is kafka-topics.sh --alter.

Use kafka-configs.sh --alter starting with version 0.9.0.

42. Differentiate between Kafka streams and Sp