Broker configuration basics in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the broker ID in the Kafka server properties.

Kafka

broker.id=[1]

Drag options to blanks, or click blank then click option'

A"broker1"

B1

Ctrue

Dlocalhost

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string instead of an integer for broker.id

Setting broker.id to true or localhost

The broker.id must be a unique integer for each Kafka broker.

2fill in blank

medium

Complete the code to specify the port number the Kafka broker listens on.

Kafka

listeners=PLAINTEXT://:[1]

Drag options to blanks, or click blank then click option'

A9092

B2181

C9090

D8080

Attempts:

3 left

💡 Hint

Common Mistakes

Using port 8080 which is common for web servers

Using port 2181 which is for Zookeeper

The default Kafka broker port is 9092.

3fill in blank

hard

Fix the error in the configuration line to correctly set the log directory.

Kafka

log.dirs=[1]

Drag options to blanks, or click blank then click option'

A/var/lib/kafka logs

Bvar/lib/kafka-logs

C/var/lib/kafka-logs

D/var/lib/kafka_logs

Attempts:

3 left

💡 Hint

Common Mistakes

Missing leading slash making path relative

Including spaces in directory names

The log directory path must be an absolute path without spaces.

4fill in blank

hard

Fill both blanks to configure the number of partitions and replication factor for a topic.

Kafka

num.partitions=[1]
default.replication.factor=[2]

Drag options to blanks, or click blank then click option'

A3

B1

C2

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Setting replication factor higher than number of brokers

Using 1 partition which limits parallelism

Common default settings are 3 partitions and replication factor of 2 for fault tolerance.

5fill in blank

hard

Fill all three blanks to configure the broker's advertised listeners and log retention time.

Kafka

advertised.listeners=[1]
listener.security.protocol.map=[2]
log.retention.hours=[3]

Drag options to blanks, or click blank then click option'

APLAINTEXT://broker1:9092

BPLAINTEXT:PLAINTEXT

C168

DSSL

Attempts:

3 left

💡 Hint

Common Mistakes

Using only hostname without protocol in advertised.listeners

Setting retention time too low or too high without reason

The advertised listener must include protocol and address, the protocol map defines security, and retention is in hours (168 = 7 days).

Practice

1. What is the main purpose of Kafka broker configuration files?

easy

A. To set key=value pairs that control broker behavior

B. To write Kafka client application code

C. To store user data permanently

D. To configure the operating system settings

Solution

1. Step 1: Understand the role of broker configuration

   Broker configuration files contain settings that control how Kafka brokers behave, such as storage and network handling.

2. Step 2: Identify the correct description

   Only To set key=value pairs that control broker behavior correctly describes the purpose as setting key=value pairs for broker behavior.

3. Final Answer:

   To set key=value pairs that control broker behavior -> Option A

4. Quick Check:

   Broker config = key=value pairs [OK]

Hint: Broker config files set key=value pairs for broker control [OK]

Common Mistakes:

• Confusing broker config with client code
• Thinking config stores user data
• Mixing OS settings with Kafka broker config

2. Which of the following is the correct syntax to set the broker ID in Kafka's configuration file?

easy

A. broker_id=1

B. broker-id:1

C. broker.id=1

D. brokerId=1

Solution

1. Step 1: Recall Kafka config syntax

   Kafka uses key=value pairs with dots to separate words, like broker.id=1.

2. Step 2: Compare options

   Only broker.id=1 uses the correct dot notation and equal sign syntax.

3. Final Answer:

   broker.id=1 -> Option C

4. Quick Check:

   Correct syntax uses dot and equal sign [OK]

Hint: Kafka configs use dot notation and equal sign [OK]

Common Mistakes:

• Using underscores instead of dots
• Using colon instead of equal sign
• CamelCase keys instead of lowercase with dots

3. Given this Kafka broker configuration snippet:

log.dirs=/tmp/kafka-logs
num.network.threads=3
num.io.threads=8

What does num.network.threads=3 control?

medium

A. Number of threads for message processing

B. Number of threads writing logs to disk

C. Number of threads for client connections

D. Number of threads handling network requests

Solution

1. Step 1: Understand the meaning of num.network.threads

   This setting controls how many threads the broker uses to handle network requests from clients.

2. Step 2: Match options with setting

   Number of threads handling network requests correctly states it controls threads handling network requests; others describe unrelated functions.

3. Final Answer:

   Number of threads handling network requests -> Option D

4. Quick Check:

   num.network.threads = network threads count [OK]

Hint: network.threads means threads for network requests [OK]

Common Mistakes:

• Confusing network threads with IO threads
• Thinking it controls log writing threads
• Mixing client connections with message processing

4. You see this broker config line:

log.retention.hours 168

What is wrong with this line?

medium

A. Missing equal sign between key and value

B. Invalid value; hours must be a string

C. Key name is incorrect; should be log.retention.ms

D. No error; this line is correct

Solution

1. Step 1: Check syntax for key-value pairs

   Kafka config requires an equal sign (=) between key and value, not just a space.

2. Step 2: Identify the error in the line

   The line uses a space instead of '=', so it is a syntax error.

3. Final Answer:

   Missing equal sign between key and value -> Option A

4. Quick Check:

   Config lines need key=value format [OK]

Hint: Config lines must have key=value, not space [OK]

Common Mistakes:

• Assuming space works as separator
• Confusing retention hours with milliseconds
• Thinking the key name is wrong

5. You want to configure a Kafka broker to store logs in two directories: /data/kafka1 and /data/kafka2. Which is the correct way to set log.dirs in the broker config?

hard

A. log.dirs=/data/kafka1;/data/kafka2

B. log.dirs=/data/kafka1,/data/kafka2

C. log.dirs=/data/kafka1 /data/kafka2

D. log.dirs=[/data/kafka1,/data/kafka2]

Solution

1. Step 1: Understand log.dirs format

   Kafka expects multiple directories separated by commas without spaces or brackets.

2. Step 2: Evaluate each option

   log.dirs=/data/kafka1,/data/kafka2 uses commas correctly; B uses semicolon (wrong), C uses space (wrong), D uses brackets (wrong).

3. Final Answer:

   log.dirs=/data/kafka1,/data/kafka2 -> Option B

4. Quick Check:

   Multiple dirs separated by commas [OK]

Hint: Separate multiple log dirs with commas, no spaces [OK]

Common Mistakes:

• Using semicolons or spaces instead of commas
• Adding brackets around paths
• Including spaces between paths