Exposing Kafka from kind to a Local Windows Application

In our previous blog post, we discussed a workaround for the DNS error that occurs when an application running on a local Windows machine connects to Kafka. In this post, we will discuss the proper solution.

Our Kafka cluster runs inside Docker through a local kind Kubernetes cluster rather than directly on the host machine. Kafka advertises broker addresses using Kubernetes DNS names, which can be resolved from inside the cluster but not by an application running on Windows. To make Kafka reachable from the host, we must expose the required ports from the kind node container to the host machine.

Troubleshooting Kafka DNS Resolution from a Local .NET Application

This blog explains a DNS resolution error that can occur when testing an event-driven .NET application locally with Kafka running in a kind cluster. You’ll learn what causes the issue and how to apply a practical workaround to get your local development environment working quickly.

Pre-requisites:

• A Kafka cluster running on a local Kind cluster.

• Strimzi configured to manage the Kafka cluster.

• A .NET API capable of creating or publishing to Kafka.

• kubectl configured to access your Kind cluster.

• PowerShell running on Windows.

• The BootstrapServers value is intentionally set to, localhost:9092 in appsettings.json