Kafka 4.2.0 on Kubernetes - Complete Setup Guide - Exposed to Internet

3-broker Kafka cluster on k3s with KRaft, SASL/SCRAM, and external access via Traefik. Before you start — get your Traefik IP: kubectl get svc traefik -n kube-system Copy any IP from the EXTERNAL-IP column. Replace every occurrence of 192.168.1.119 in the YAMLs below with your actual IP. Stage 1 — Bootstrap Apply all of these files in order. This stage starts the cluster with port 9094 open (no auth) so you can register SCRAM credentials. 1.1 namespace.yaml apiVersion : v1 kind : Namespace metadata : name : kafka kubectl apply -f namespace.yaml 1.2 kafka-jaas.yaml apiVersion : v1 kind : ConfigMap metadata : name : kafka-jaas namespace : kafka data : jaas.conf : | KafkaServer { org.apache.kafka.common.security.scram.ScramLoginModule required username="admin" password="supersecret"; }; kubectl apply -f kafka-jaas.yaml 1.3 kafka-sasl.yaml apiVersion : v1 kind : Secret metadata : name : kafka-sasl namespace : kafka type : Opaque stringData : username : admin password : supersecret kubectl