Apache Kafka Practice Exam 2025 – The Complete All-in-One Guide for Exam Success!

A producer receives a LeaderNotAvailableException when there is no available leader for the partition to which it is attempting to send messages. This situation typically arises during the leader election process, which occurs when the current leader becomes unavailable or when a new partition is created and a leader has not yet been elected. During this time, the producer cannot route messages to the designated partition, leading to the exception.

This scenario highlights the importance of understanding the Kafka architecture, specifically the roles of leaders and followers in managing partitions. A producer needs to interact with the correct leader to ensure data is written effectively, and if this leader is not available, the producer will experience this specific exception.

In contrast, the other options do not align with the conditions that result in this exception. For instance, message writing and reaching buffer limits pertain to different operational states in Kafka, while having no available brokers is indicative of a cluster-wide issue rather than a problem with leader availability for a specific partition.