In Kafka Connect, sink connectors consume data from Kafka topics and send it to external systems (e.g., databases, object storage, search indexes).

From Kafka documentation:

“Sink connectors receive data from Kafka topics and write it to external systems.”

A → Correct: Moves data out of Kafka.

B → Moves data into Kafka.

C → Not a connector type.

D → Not a standard connector classification.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 8, p. 241

Apache Kafka Documentation: Kafka Connect – Sink Connectors

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Kafka's Controller is a broker that also performs controller duties. It is not a dedicated node. Therefore, it continues to host topics, partitions, and leaders just like any other broker.

From Kafka documentation:

“The controller is one of the brokers in the cluster and continues to perform all normal broker functions.”

A → Correct: The controller is also a normal broker with partitions.

B/C/D → Incorrect: Replication and consumer fetches are not tied to the controller.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 6, p. 190

Apache Kafka Documentation: Kafka Controller Behavior

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Kafka relies on ZooKeeper heartbeats to track broker health. If the broker JVM is unresponsive due to long GC pauses, ZooKeeper won’t receive timely heartbeats and will mark the broker as dead.

From Kafka Documentation:

“If the garbage collection pause is too long, the broker will not send heartbeats to ZooKeeper and will be considered dead. Leadership and partition reassignments will then occur.”

B → Correct: Broker marked dead, causes partition leadership transfers.

A → Incorrect: Log cleaner thread is unrelated to JVM pauses.

C → Incorrect: Clients may be impacted, but this is not the first result.

D → Incorrect: This is a normal OS function, not caused by GC issues.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 10, p. 305

Kafka Official Docs: "ZooKeeper Timeout and Broker Health"

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Apache Kafka's built-in ACL mechanism (SimpleAclAuthorizer) stores ACL data in ZooKeeper. ACLs are propagated to brokers from ZooKeeper and cached in memory for fast lookup.

From Kafka documentation:

“ACLs are stored in ZooKeeper under /kafka-acl and are loaded into each broker at startup and on updates.”

B → Correct: ZooKeeper stores ACLs centrally.

A → Brokers load ACLs but don’t persist them.

C & D → Do not store or manage ACLs.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 9, p. 285

Apache Kafka Documentation: Authorizer Configuration

Kafka Connect is a framework for connecting Kafka with external systems like databases, key-value stores, file systems, etc. It handles ingestion and egress of data using scalable and fault-tolerant connectors.

From Kafka documentation:

“Kafka Connect is a scalable and fault-tolerant component for efficiently streaming data between Kafka and other systems.”

A → Correct: Purpose-built for data integration.

B → For stream processing, not integration.

C → Manages schemas, not data movement.

D → For HTTP-based Kafka interaction.

Page Reference:

Kafka: The Definitive Guide, 1st Edition, Chapter 8, p. 239–241

Apache Kafka Documentation: Kafka Connect Overview

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The Kafka REST Proxy, provided as part of Confluent Platform, allows clients to interact with Kafka over REST APIs. When securing communication between REST Proxy and REST clients, it uses TLS (HTTPS).

As per the official Confluent documentation for REST Proxy security:

“The REST Proxy supports HTTPS to encrypt communication between REST clients and the REST Proxy.”

TLS/SSL encryption ensures that data in transit is secure and private.

Other options listed, such as MD5 (a hashing algorithm), SCRAM (an authentication mechanism), and Kerberos (an authentication protocol), do not provide direct encryption of the communication channel itself for REST Proxy. They can be part of broader security configurations (e.g., SCRAM for Kafka brokers, Kerberos for SASL authentication), but TLS (HTTPS) is the explicit mechanism for encrypting data between the REST Proxy and its clients.

Page Reference:

Confluent Kafka: The Definitive Guide, 1st Edition, Chapter 9 (“Kafka Security”), Section “REST Proxy Security” (p. 288–289).

Confluent Platform REST Proxy Documentation, “Encryption (HTTPS)”.