CCDAK Exam Dumps : Confluent Certified Developer for Apache Kafka Certification Examination

Session windows are ideal for tracking periods of activity separated by inactivity, such as user sessions.

From Kafka Streams Documentation > Windowing:

“A session window captures streams of events that are intermittent and separated by a gap of inactivity.”

Tumbling/Hopping/Sliding windows are fixed in size

Session windows are dynamic and close after inactivity timeout

This makes them perfect for identifying gaps in user interaction.

With acks=all and min.insync.replicas=2, Kafka requires at least two in-sync replicas to acknowledge a write. If only one broker is alive, the condition fails, and NotEnoughReplicasException is thrown by the producer.

From Kafka Producer Exception Docs:

“NotEnoughReplicasException is thrown when the number of in-sync replicas is insufficient to satisfy acks=all with min.insync.replicas.”

NetworkException is generic and not raised here.

NotCoordinatorException is related to consumer group coordination.

NotLeaderForPartitionException is unrelated unless accessing an unassigned leader.

RetriableException is a subclass of KafkaException, indicating transient issues that might succeed if retried. Examples include:

LeaderNotAvailableException: Happens when metadata is not yet propagated or leader election is in progress.

NotEnoughReplicasException: Happens when the number of in-sync replicas is insufficient. This can be transient if replicas come back online.

From the Apache Kafka Java Client documentation:

"These exceptions (like LeaderNotAvailableException, NotEnoughReplicasException) are transient and the client will retry them automatically depending on retry configuration."

RecordTooLargeException and AuthorizationException are non-retriable as they indicate client-side or permission errors.