Kafka Topic InvalidReplicationFactorException

The replication factor is larger than the number of available brokers.

Understanding Kafka and Its Purpose

Apache Kafka is a distributed event streaming platform used by thousands of companies for high-performance data pipelines, streaming analytics, data integration, and mission-critical applications. Kafka is designed to handle real-time data feeds, providing a robust and scalable solution for managing data streams.

Identifying the Symptom: InvalidReplicationFactorException

When working with Kafka, you might encounter the InvalidReplicationFactorException. This error typically occurs when attempting to create a topic with a replication factor that exceeds the number of available brokers in the Kafka cluster. The replication factor determines how many copies of the data are maintained across different brokers to ensure reliability and fault tolerance.

Observed Error Message

The error message might look like this:

InvalidReplicationFactorException: Replication factor: 3 larger than available brokers: 2

Explaining the Issue

The InvalidReplicationFactorException is thrown because Kafka cannot fulfill the request to replicate the topic data across the specified number of brokers. This is a critical configuration issue that needs to be addressed to ensure data redundancy and reliability.

Why This Happens

This issue arises when the replication factor specified during topic creation is greater than the number of brokers currently available in the Kafka cluster. For example, if you have a replication factor of 3 but only 2 brokers, Kafka cannot replicate the data as requested.

Steps to Fix the InvalidReplicationFactorException

To resolve this issue, you have two primary options: reduce the replication factor or increase the number of brokers in your Kafka cluster.

Option 1: Reduce the Replication Factor

  1. Identify the current number of brokers in your cluster. You can use the following command to list all brokers:
    bin/kafka-broker-api-versions.sh --bootstrap-server <broker-host:port>
  1. Adjust the replication factor to a number equal to or less than the number of brokers. For example, if you have 2 brokers, set the replication factor to 2 or 1.
  2. Use the following command to create the topic with the adjusted replication factor:
    bin/kafka-topics.sh --create --topic <topic-name> --partitions <num-partitions> --replication-factor <new-replication-factor> --bootstrap-server <broker-host:port>

Option 2: Add More Brokers

  1. Scale your Kafka cluster by adding more broker nodes. Ensure that the new brokers are properly configured and connected to the existing cluster.
  2. Verify the new brokers are recognized by the cluster using the broker listing command:
    bin/kafka-broker-api-versions.sh --bootstrap-server <broker-host:port>
  1. Once the new brokers are added, you can proceed with creating the topic with the desired replication factor.

Additional Resources

For more information on Kafka topic configuration and management, you can refer to the official Kafka Documentation. Additionally, the Kafka Quickstart Guide provides a comprehensive overview of setting up and managing a Kafka cluster.

Master

Kafka Topic

in Minutes — Grab the Ultimate Cheatsheet

(Perfect for DevOps & SREs)

Most-used commands
Real-world configs/examples
Handy troubleshooting shortcuts
Your email is safe with us. No spam, ever.

Thankyou for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.

Kafka Topic

Cheatsheet

(Perfect for DevOps & SREs)

Most-used commands
Your email is safe with us. No spam, ever.

Thankyou for your submission

We have sent the cheatsheet on your email!
Oops! Something went wrong while submitting the form.

MORE ISSUES

Made with ❤️ in Bangalore & San Francisco 🏢

Doctor Droid