When is the onCompletion() method called?

private class ProducerCallback implements Callback {

@Override

public void onCompletion(RecordMetadata recordMetadata, Exception e) {

if (e != null) {

e.printStackTrace();

}

}

}

ProducerRecord record =

new ProducerRecord<>("topic1", "key1", "value1");

producer.send(record, new ProducerCallback());

In Kafka Streams, by what value are internal topics prefixed by?

You are receiving orders from different customer in an "orders" topic with multiple partitions. Each message has the customer name as the key. There is a special customer named ABC that generates a lot of orders and you would like to reserve a partition exclusively for ABC. The rest of the message should be distributed among other partitions. How can this be achieved?

In the Kafka consumer metrics it is observed that fetch-rate is very high and each fetch is small. What steps will you take to increase throughput?

What is returned by a producer.send() call in the Java API?

You are using JDBC source connector to copy data from a table to Kafka topic. There is one connector created with max.tasks equal to 2 deployed on a cluster of 3 workers. How many tasks are launched?

A producer application in a developer machine was able to send messages to a Kafka topic. After copying the producer application into another developer's machine, the producer is able to connect to Kafka but unable to produce to the same Kafka topic because of an authorization issue. What is the likely issue?

You are running a Kafka Streams application in a Docker container managed by Kubernetes, and upon application restart, it takes a long time for the docker container to replicate the state and get back to processing the data. How can you improve dramatically the application restart?

What Java library is KSQL based on?

How can you gracefully make a Kafka consumer to stop immediately polling data from Kafka and gracefully shut down a consumer application?

Which of the following errors are retriable from a producer perspective? (select two)

Which of the following is true regarding thread safety in the Java Kafka Clients?

A Zookeeper configuration has tickTime of 2000, initLimit of 20 and syncLimit of 5. What's the timeout value for followers to connect to Zookeeper?

Where are KSQL-related data and metadata stored?

Consumer failed to process record # 10 and succeeded in processing record # 11. Select the course of action that you should choose to guarantee at least once processing

Which of the following is not an Avro primitive type?

By default, which replica will be elected as a partition leader? (select two)

To prevent network-induced duplicates when producing to Kafka, I should use

Where are the ACLs stored in a Kafka cluster by default?