Kafka Helm chart

The kafka helm chart is not maintained by CORD, but it is available online at: https://github.com/kubernetes/charts/tree/master/incubator/kafka

To install kafka using the cord-kafka name, create a YAML values file to configure Kafka (for developers, this is in helm-charts/example/kafka-single.yaml):

---
# Deploy a single replica of Kafka during development

# configuration ref: https://kafka.apache.org/documentation/#configuration
configurationOverrides:
  "offsets.topic.replication.factor": 1
  "log.retention.hours": 4
  "log.message.timestamp.type": "LogAppendTime"

replicas: 1

persistence:
  enabled: false

zookeeper:
  replicaCount: 1
  persistence:
    enabled: false

Then run the following commands to start Kafka:

helm repo add incubator http://storage.googleapis.com/kubernetes-charts-incubator
helm install -f kafka-single.yaml --version 0.8.8 -n cord-kafka incubator/kafka

NOTE: Historically there were two kafka busses deployed (another one named voltha-kafka) but these have been consolidated.

Viewing events with kafkacat

As a debugging tool you can deploy a container containing kafkacat and use that to listen for events:

helm install -n kafkacat cord/kafkacat

Once the container is up and running you can exec into the pod and run kafkacat to perform various diagnostic commands.

kubectl exec -it kafkacat-##########-##### bash

For a complete reference, please refer to the kafkacat guide

A few examples:

• List available topics:

kafkacat -b cord-kafka -L

• Listen for events on a particular topic:

kafkacat -b cord-kafka -C -t <kafka-topic>

• Some example topics to listen on:

kafkacat -b cord-kafka -C -t xos.log.core
kafkacat -b cord-kafka -C -t xos.gui_events
kafkacat -b cord-kafka -C -t voltha.events
kafkacat -b cord-kafka -C -t onu.events
kafkacat -b cord-kafka -C -t authentication.events
kafkacat -b cord-kafka -C -t dhcp.events