Cross-datacenter replication in Kafka - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the source Kafka cluster for replication.

Kafka

replication.source.cluster = "[1]"

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

Asource-cluster

Bus-east-1

Cdestination-cluster

Dreplica-cluster

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing source and destination cluster names.

Using region names instead of cluster identifiers.

The source cluster is the Kafka cluster where data originates. Here, it is named "source-cluster".

2fill in blank

medium

Complete the code to specify the destination Kafka cluster for replication.

Kafka

replication.destination.cluster = "[1]"

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

Asource-cluster

Bprimary-cluster

Cbackup-cluster

Ddestination-cluster

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up source and destination cluster names.

Using unrelated cluster names.

The destination cluster is where the data is replicated to. It is named "destination-cluster" here.

3fill in blank

hard

Fix the error in the replication topic configuration to enable replication.

Kafka

replication.topic = "[1]"

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

Areplicated-topic

Btopic-replica

Creplication-topic

Dtopic

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic or incorrect topic names.

Confusing topic names with cluster names.

The replication topic must be correctly named to match the source topic being replicated. "replicated-topic" is the correct name here.

4fill in blank

hard

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

Kafka

replication.topic.config = {"replication.factor": [1], "partitions": [2]

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

A3

B5

C10

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Setting replication factor too low or too high.

Choosing too few partitions for workload.

The replication factor is set to 3 to ensure fault tolerance, and the number of partitions is set to 10 for parallelism.

5fill in blank

hard

Fill all three blanks to complete the replication configuration with topic name, replication factor, and partitions.

Kafka

replication.config = {"topic": "[1]", "replication.factor": [2], "partitions": [3]

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

Areplicated-topic

B3

C10

Dsource-topic

Attempts:

3 left

💡 Hint

Common Mistakes

Using source topic name instead of replicated topic.

Incorrect replication factor or partition count.

The topic to replicate is "replicated-topic" with a replication factor of 3 and 10 partitions for performance and reliability.

Practice

1.

What is the main purpose of cross-datacenter replication in Kafka?

easy

A. To copy Kafka topics between clusters for data safety and availability

B. To compress Kafka messages for faster transmission

C. To encrypt Kafka topics for security

D. To delete old Kafka topics automatically

Solution

1. Step 1: Understand the concept of cross-datacenter replication

   Cross-datacenter replication means copying data from one Kafka cluster to another in a different location.

2. Step 2: Identify the main goal of this replication

   The goal is to keep data safe and available even if one cluster fails.

3. Final Answer:

   To copy Kafka topics between clusters for data safety and availability -> Option A

4. Quick Check:

   Replication = Data safety and availability [OK]

Hint: Replication means copying data across clusters for safety [OK]

Common Mistakes:

• Confusing replication with compression
• Thinking replication encrypts data
• Assuming replication deletes data

2.

Which of the following is the correct way to specify the source cluster's bootstrap servers in Kafka MirrorMaker configuration?

consumer.bootstrap.servers = ?

easy

A. "source.kafka.cluster:9092"

B. "target.kafka.cluster:9092"

C. "localhost:2181"

D. "mirror.kafka.cluster:2181"

Solution

1. Step 1: Identify the role of consumer.bootstrap.servers

   This property tells MirrorMaker where to read data from, so it must point to the source Kafka cluster.

2. Step 2: Choose the correct server address for the source cluster

   The source cluster's Kafka broker address is usually in the form host:port, like "source.kafka.cluster:9092".

3. Final Answer:

   "source.kafka.cluster:9092" -> Option A

4. Quick Check:

   consumer.bootstrap.servers = source cluster address [OK]

Hint: Consumer connects to source cluster bootstrap servers [OK]

Common Mistakes:

• Using target cluster address for consumer.bootstrap.servers
• Using ZooKeeper address instead of Kafka broker
• Confusing consumer and producer properties

3.

Given the following MirrorMaker configuration snippet, what will be the value of producer.bootstrap.servers?

consumer.bootstrap.servers=source1.kafka:9092,source2.kafka:9092
producer.bootstrap.servers=target.kafka:9092

medium

A. "source1.kafka:9092,source2.kafka:9092"

B. "target.kafka:9092"

C. "source1.kafka:9092"

D. "localhost:9092"

Solution

1. Step 1: Read the configuration lines carefully

   The snippet shows two properties: consumer.bootstrap.servers and producer.bootstrap.servers with their values.

2. Step 2: Identify the value assigned to producer.bootstrap.servers

   It is explicitly set to "target.kafka:9092" in the second line.

3. Final Answer:

   "target.kafka:9092" -> Option B

4. Quick Check:

   producer.bootstrap.servers = target cluster address [OK]

Hint: Producer connects to target cluster bootstrap servers [OK]

Common Mistakes:

• Mixing consumer and producer server addresses
• Assuming producer uses source cluster address
• Ignoring explicit configuration values

4.

Identify the error in this MirrorMaker consumer configuration:

consumer.bootstrap.servers=target.kafka:9092
consumer.group.id=mirror-group

medium

A. consumer.bootstrap.servers should use port 2181

B. consumer.group.id is missing

C. consumer.bootstrap.servers should point to the source cluster, not target

D. consumer.group.id should be unique per topic

Solution

1. Step 1: Understand the role of consumer.bootstrap.servers

   This property must point to the source Kafka cluster to read data for replication.

2. Step 2: Check the given value

   It incorrectly points to "target.kafka:9092", which is the destination cluster, not the source.

3. Final Answer:

   consumer.bootstrap.servers should point to the source cluster, not target -> Option C

4. Quick Check:

   Consumer connects to source cluster [OK]

Hint: Consumer must connect to source cluster, not target [OK]

Common Mistakes:

• Using target cluster address for consumer.bootstrap.servers
• Confusing ZooKeeper port with Kafka broker port
• Assuming group.id is missing when it is present

5.

You want to replicate only topics starting with logs- from the source cluster to the target cluster using MirrorMaker. Which configuration property should you set to filter these topics?

hard

A. consumer.topic.filter=logs-*

B. producer.topic.filter=logs-*

C. mirror.topic.prefix=logs-

D. consumer.topic.whitelist=logs-*

Solution

1. Step 1: Identify the property to filter topics in MirrorMaker

   MirrorMaker uses consumer.topic.whitelist to specify which topics to consume from the source cluster.

2. Step 2: Match the pattern for topics starting with 'logs-'

   The pattern "logs-*" matches all topics starting with "logs-".

3. Final Answer:

   consumer.topic.whitelist=logs-* -> Option D

4. Quick Check:

   Use consumer.topic.whitelist to filter topics [OK]

Hint: Use consumer.topic.whitelist to select topics by pattern [OK]

Common Mistakes:

• Using producer.topic.filter which does not exist
• Confusing mirror.topic.prefix with filtering
• Using consumer.topic.filter instead of whitelist