Confluent Open Source Helm Chart

• Description
• Software
• Environment Preparation
  • Create a Kubernetes Cluster
  • Install Helm on the Kubernetes
• Installation
  • Clone the repo
  • Install Chart
  • Verify Installation(Optional)
    • Helm Test
    • Manual Test
      • Zookeeper
      • Kafka
  • Uninstall / Cleanup
• Operations
  • Scale In/Out
  • Monitoring
• Work In Progress
• Huge Thanks

Description

This is Helm Chart for deploying Confluent Open Source on Kubernetes, which include:

• Confluent Kafka
• Confluent Zookeeper
• Confluent Schema Registry
• Confluent Kafka REST Proxy
• Confluent Kafka Connect

Software

• Kubernetes 1.9.2+
• Helm 2.8.2+
• Confluent Platform Open Source Docker Images 4.1.1

Environment Preparation

Create a Kubernetes Cluster

Different options of creating a Kubernetes Cluster:

1. Minikube, https://github.com/kubernetes/minikube.
2. Google Kubernetes Engine, https://cloud.google.com/kubernetes-engine/docs/quickstart.

Install Helm on the Kubernetes

Follow Helm's quickstart to install and deploy Helm to the k8s cluster.

Run helm ls to verify the local installation.

NOTE: For Helm versions prior to 2.9.1, you may see "connect: connection refused", and will need to fix up the deployment before proceeding.

# Fix up the Helm deployment, if needed:
kubectl delete --namespace kube-system svc tiller-deploy
kubectl delete --namespace kube-system deploy tiller-deploy
kubectl create serviceaccount --namespace kube-system tiller
kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller
kubectl patch deploy --namespace kube-system tiller-deploy -p '{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}'      
helm init --service-account tiller --upgrade

Installation

Clone the repo

git clone https://github.com/confluentinc/cp-helm-charts.git

Install cp-helm-chart

• The steps below will install a 3 node cp-zookeeper, a 3 node cp-kafka cluster,1 schema registry,1 rest proxy and 1 kafka connect in your k8s env.

helm install cp-helm-charts

• To install with a specific name, you can do:

$ helm install --name my-confluent-oss cp-helm-charts

• To install without rest proxy, schema registry and kafka connect

helm install --set cp-schema-registry.enabled=false,cp-kafka-rest.enabled=false,cp-kafka-connect.enabled=false cp-helm-charts/

Verify Installation(Optional)

Helm Test

helm test <release name> will run the embedded test pod in each sub-chart to verify installations

Manual Test

Zookeeper

1. Deploy a zookeeper client pod

   kubectl apply -f cp-helm-charts/examples/zookeeper-client.yaml
   

2. Log into the Pod

   kubectl exec -it zookeeper-client -- /bin/bash
   

3. Use zookeeper-shell to connect in the zookeeper-client Pod:

   zookeeper-shell <zookeeper service>:<port>
   

4. Explore with zookeeper commands, for example:

   # Gives the list of active brokers
   ls /brokers/ids
   
   # Gives the list of topics
   ls /brokers/topics
   
   # Gives more detailed information of the broker id '0'
   get /brokers/ids/0
   

Kafka

1. Deploy a kafka client pod

   kubectl apply -f cp-helm-charts/examples/kafka-client.yaml
   

2. Log into the Pod

   kubectl exec -it kafka-client -- /bin/bash
   

3. Explore with kafka commands:

   ## Setup
   export RELEASE_NAME=<release name>
   export ZOOKEEPERS=${RELEASE_NAME}-cp-zookeeper:2181
   export KAFKAS=${RELEASE_NAME}-cp-kafka-headless:9092
   
   ## Create Topic
   kafka-topics --zookeeper $ZOOKEEPERS --create --topic test-rep-one --partitions 6 --replication-factor 1
   
   ## Producer
   kafka-run-class org.apache.kafka.tools.ProducerPerformance --print-metrics --topic test-rep-one --num-records 6000000 --throughput 100000 --record-size 100 --producer-props bootstrap.servers=$KAFKAS buffer.memory=67108864 batch.size=8196
   
   ## Consumer
   kafka-consumer-perf-test --broker-list $KAFKAS --messages 6000000 --threads 1 --topic test-rep-one --print-metrics
   

Uninstall / Cleanup

helm ls # to check find out release name
helm delete <release name>

# delete all pvc created by this release
kubectl delete pvc --selector=release=<release name>

Operations

Scale In/Out

NOTE: All Scale In/Out operations should be done offline with no producer/consumer connection

Zookeeper

Install co-helm-charts with default 3 nodes zookeeper ensemble

helm install cp-helm-charts

Scale zookeeper nodes out to 5, change servers under cp-zookeeper to 5 in values.yaml

helm upgrade <release name> cp-helm-charts

Scale zookeeper nodes out to 5, change servers under cp-zookeeper to 3 in values.yaml

helm upgrade <release name> cp-helm-charts

Kafka

NOTE: Scaling in/out Kafka brokers without doing Partition Reassignment will cause data loss!!
Be sure to reassign partitions correctly before scaling in/out Kafka cluster. Please refer: https://kafka.apache.org/documentation/#basic_ops_cluster_expansion

Install co-helm-charts with default 3 brokers kafka cluster

helm install cp-helm-charts

Scale kafka brokers out to 5, change brokers under cp-kafka to 5 in values.yaml

helm upgrade <release name> cp-helm-charts

Scale kafka brokers out to 5, change brokers under cp-kafka to 3 in values.yaml

helm upgrade <release name> cp-helm-charts

Monitoring

JMX Metrics are enabled by default for all components, Prometheus JMX Exporter is installed as a sidecar container along with all Pods.

1. Install Prometheus and Grafana in same Kubernetes cluster using helm

   helm install stable/prometheus
   helm install stable/grafana
   

2. Add Prometheus as Data Source in Grafana, url should be something like: http://illmannered-marmot-prometheus-server:80

3. Import dashboard under grafana-dashboard into Grafana

   

TODO

External Access

Security

Logging

Upgrade

Huge Thanks

Huge thanks to:

• Kafka helm chart
• Zookeeper helm chart
• Schema Registry helm chart
• kubernetes-kafka
• docker-kafka