Confluent CCDAK Exam Practice Test Instant Access

Question 1

You want to sink data from a Kafka topic to S3 using Kafka Connect. There are 10 brokers in the cluster, the topic has 2 partitions with replication factor of 3. How many tasks will you configure for the S3 connector?

A10

Answer : D

You cannot have more sink tasks (= consumers) than the number of partitions, so 2.

Question 2

A consumer wants to read messages from a specific partition of a topic. How can this be achieved?

ACall subscribe(String topic, int partition) passing the topic and partition number as the arguments

BCall assign() passing a Collection of TopicPartitions as the argument

CCall subscribe() passing TopicPartition as the argument

Answer : B

assign() can be used for manual assignment of a partition to a consumer, in which case subscribe() must not be used. Assign() takes a collection of TopicPartition object as an argument https://kafka.apache.org/23/javadoc/org/apache/kafka/clients/consumer/KafkaConsumer.html#assign-java.util.Collection-

Question 3

When auto.create.topics.enable is set to true in Kafka configuration, what are the circumstances under which a Kafka broker automatically creates a topic? (select three)

AClient requests metadata for a topic

BConsumer reads message from a topic

CClient alters number of partitions of a topic

DProducer sends message to a topic

Answer : A, B, D

A kafka broker automatically creates a topic under the following circumstances- When a producer starts writing messages to the topic - When a consumer starts reading messages from the topic - When any client requests metadata for the topic

Question 4

What is the risk of increasing max.in.flight.requests.per.connection while also enabling retries in a producer?

AAt least once delivery is not guaranteed

BMessage order not preserved

CReduce throughput

DLess resilient

Answer : B

Some messages may require multiple retries. If there are more than 1 requests in flight, it may result in messages received out of order. Note an exception to this rule is if you enable the producer settingenable.idempotence=true which takes care of the out of ordering case on its own. Seehttps://issues.apache.org/jira/browse/KAFKA-5494

Question 5

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

Amax.in.flight.requests.per.connection=1

Benable.idempotence=true

Cretries=200000

Dbatch.size=1

Answer : B

Producer idempotence helps prevent the network introduced duplicates. More details herehttps://cwiki.apache.org/confluence/display/KAFKA/Idempotent+Producer

Question 6

You are sending messages with keys to a topic. To increase throughput, you decide to increase the number of partitions of the topic. Select all that apply.

AAll the existing records will get rebalanced among the partitions to balance load

BNew records with the same key will get written to the partition where old records with that key were written

CNew records may get written to a different partition

DOld records will stay in their partitions

Answer : C, D

Increasing the number of partition causes new messages keys to get hashed differently, and breaks the guarantee 'same keys goes to the same partition'. Kafka logs are immutable and the previous messages are not re-shuffled

Question 7

To produce data to a topic, a producer must provide the Kafka client with...

Athe list of brokers that have the data, the topic name and the partitions list

Bany broker from the cluster and the topic name and the partitions list

Call the brokers from the cluster and the topic name

Dany broker from the cluster and the topic name

Answer : D

All brokers can respond to a Metadata request, so a client can connect to any broker in the cluster and then figure out on its own which brokers to send data to.

Confluent CCDAK Certified Developer for Apache Kafka Exam Practice Test