Broker nodes in Kafka - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

What is the primary role of a Kafka broker node?

In a Kafka cluster, what is the main job of a broker node?

A Receive messages from producers, store them, and serve to consumers

B Manage the cluster's Zookeeper ensemble

C Only produce messages to topics

D Handle client authentication exclusively

💡 Hint

Think about where messages are kept and how clients get them.

A Kafka broker node receives messages from producers, stores them, and serves them to consumers. It manages partitions and handles data storage and retrieval.

❓ Predict Output

intermediate

What output does this Kafka broker configuration produce?

Given this Kafka broker configuration snippet, what will be the broker's advertised listener port?

Kafka

listeners=PLAINTEXT://0.0.0.0:9092
advertised.listeners=PLAINTEXT://broker1.example.com:9094

A 9094

B 9092

C 0.0.0.0

D broker1.example.com

💡 Hint

Advertised listeners tell clients how to connect.

The advertised.listeners setting tells clients the hostname and port to use, so the port is 9094.

🔧 Debug

advanced

Why does this Kafka broker fail to start?

Examine the following Kafka broker configuration snippet. Why will the broker fail to start?

Kafka

broker.id=1
listeners=PLAINTEXT://:9092
advertised.listeners=PLAINTEXT://localhost:9092
log.dirs=/tmp/kafka-logs

A log.dirs path is invalid

B broker.id must be zero or greater

C listeners missing hostname causes startup failure

D advertised.listeners cannot use localhost

💡 Hint

Check the listeners setting format carefully.

The listeners setting requires a hostname or IP before the port. ':9092' is invalid and causes startup failure.

📝 Syntax

advanced

Which option correctly defines multiple listeners for a Kafka broker?

Choose the correct syntax to configure two listeners: one PLAINTEXT on port 9092 and one SSL on port 9093.

A listeners=PLAINTEXT://0.0.0.0:9092;SSL://0.0.0.0:9093

B listeners=PLAINTEXT://0.0.0.0:9092,SSL://0.0.0.0:9093

C listeners=[PLAINTEXT://0.0.0.0:9092, SSL://0.0.0.0:9093]

D listeners=PLAINTEXT://0.0.0.0:9092 SSL://0.0.0.0:9093

💡 Hint

Multiple listeners are separated by commas.

The correct syntax uses commas to separate listeners. Semicolons, brackets, or spaces are invalid.

🚀 Application

expert

How many partitions will broker 2 host after this assignment?

Given a Kafka cluster with 3 brokers (IDs 1, 2, 3) and a topic with 6 partitions assigned as follows:

• Partition 0: leader=1, replicas=[1,2]
• Partition 1: leader=2, replicas=[2,3]
• Partition 2: leader=3, replicas=[3,1]
• Partition 3: leader=1, replicas=[1,3]
• Partition 4: leader=2, replicas=[2,1]
• Partition 5: leader=3, replicas=[3,2]

How many partitions does broker 2 host (as leader or replica)?

A 5

B 3

C 6

D 4

💡 Hint

Count all partitions where broker 2 is either leader or in replicas.

Broker 2 is leader for partitions 1 and 4, replica for 0 and 5. Unique partitions hosted: 0, 1, 4, 5 — total 4.