CMAK (prev. Kafka Manager) for Kubernetes

CMAK (prev. Kafka Manager) is a tool for monitoring and managing Apache Kafka clusters.

CMAK operator is a Helm chart combining set of utilities, that allows to install and configure CMAK in K8s cluster.

CMAK operator comprises following components:

• CMAK, powered by CMAK docker.
• Apache ZooKeeper, powered by official Docker image.
• Custom cmak2zk tool, for configuring Kafka clusters in CMAK from YAML files.

Installation

cmak-operator chart is published into OCI compatible registry and requires Helm version >= 3.8.

It's recommended to install CMAK operator into a dedicated namespace. To install specific VERSION use following command.

helm upgrade -i --wait --create-namespace -n cmak cmak-operator \
  oci://ghcr.io/eshepelyuk/helm/cmak-operator --version <VERSION>

To install the latest version - omit --version flag from previous command.

Verify installation

By default, CMAK operator doesn't create neither Ingress nor any other K8s resources to expose UI via HTTP.

The simpliest test is to port forward CMAK UI HTTP port and access it from browser.

kubectl port-forward -n cmak service/cmak 9000

Then, open http://localhost:9000 in a browser.

Configuration

Configuration should be passed to helm via command line during installation or upgrade.

helm upgrade -i --wait --create-namespace -n cmak cmak-operator \
  oci://ghcr.io/eshepelyuk/helm/cmak-operator --version <VERSION> \
  -f cmak-values.yaml

CMAK application settings

CMAK uses configuration file /cmak/conf/application.conf. Every parameter could be overriden via JVM system property, i.e. -DmyProp=myVal. Properties are passed to CMAK container via values.yaml.

For example, to enable basic auth, add following to values.yaml.

ui:
  extraArgs:
    - "-DbasicAuthentication.enabled=true"
    - "-DbasicAuthentication.username=admin"
    - "-DbasicAuthentication.password=password"

Kafka clusters

It's extremely easy to configure multiple clusters in CMAK, starting from cluster setup, connection settings and ending with authorization, using Helm values files.

Check CMAK operator values for all available options and their description.

Minimal values.yaml configuration for adding a several Kafka clusters to CMAK.

cmak:
  clusters:
    - name: "cluster-stage"
      curatorConfig:
        zkConnect: "kafka01.stage:2181,kafka02.stage:2181"
    - name: "cluster-prod"
      curatorConfig:
        zkConnect: "kafka01.prod:2181,kafka02.prod:2181,kafka03.prod:2181"

Connection settings could be configured for all clusters at once or per selected cluster.

cmak:
  clustersCommon:
    curatorConfig:
      zkMaxRetry: 100 # <1>
  clusters:
    - name: "cluster-stage"
      kafkaVersion: "2.4.0" # <2>
      curatorConfig:
        zkConnect: "kafka01.stage:2181,kafka02.stage:2181"
    - name: "cluster-prod"
      kafkaVersion: "2.1.0" # <3>
      enabled: false
      curatorConfig:
        zkConnect: "kafka01.prod:2181,kafka02.prod:2181,kafka03.prod:2181"

1. this setting is applied to both clusters.
2. applied only to cluster-stage.
3. applied only to cluster-prod.

Alternatives

AKHQ project seems to be the most active open source tool for managing and monitoring Kafka clusters. It could be missing some functionality from CMAK, but their developers are open for feature requests and contributions.

How to contribute

Your contributions like feature suggesstions, bug reports and pull requests are always welcomed.

Please check CONTRIBUTING guide for details.