Add Kafka as a Receiver (i.e. Collector)

You can use Elasticsearch, Kafka and Fluentd as log receivers in KubeSphere. This tutorial demonstrates:

  • Deploy strimzi-kafka-operator and then create a Kafka cluster and a Kafka topic by creating Kafka and KafkaTopic CRDs.
  • Add Kafka as a log receiver to receive logs sent from Fluent Bit.
  • Verify whether the Kafka cluster is receiving logs using Kafkacat.

Prerequisites

  • You need an account granted a role including the authorization of Cluster Management. For example, you can log in to the console as admin directly or create a new role with the authorization and assign it to an account.
  • Before adding a log receiver, you need to enable any of the logging, events or auditing components. For more information, see Enable Pluggable Components. logging is enabled as an example in this tutorial.

Step 1: Create a Kafka Cluster and a Kafka Topic

You can use strimzi-kafka-operator to create a Kafka cluster and a Kafka topic. If you already have a Kafka cluster, you can start from the next step.

  1. Install strimzi-kafka-operator in the default namespace:

    helm repo add strimzi https://strimzi.io/charts/
    
    helm install --name kafka-operator -n default strimzi/strimzi-kafka-operator
    
  2. Create a Kafka cluster and a Kafka topic in the default namespace by running the following commands. The commands create Kafka and Zookeeper clusters with storage type ephemeral which is emptyDir for demonstration purposes. For other storage types in a production environment, refer to kafka-persistent.

    cat <<EOF | kubectl apply -f -
    apiVersion: kafka.strimzi.io/v1beta1
    kind: Kafka
    metadata:
      name: my-cluster
      namespace: default
    spec:
      kafka:
        version: 2.5.0
        replicas: 3
        listeners:
          plain: {}
          tls: {}
        config:
          offsets.topic.replication.factor: 3
          transaction.state.log.replication.factor: 3
          transaction.state.log.min.isr: 2
          log.message.format.version: '2.5'
        storage:
          type: ephemeral
      zookeeper:
        replicas: 3
        storage:
          type: ephemeral
      entityOperator:
        topicOperator: {}
        userOperator: {}
    ---
    apiVersion: kafka.strimzi.io/v1beta1
    kind: KafkaTopic
    metadata:
      name: my-topic
      namespace: default
      labels:
        strimzi.io/cluster: my-cluster
    spec:
      partitions: 3
      replicas: 3
      config:
        retention.ms: 7200000
        segment.bytes: 1073741824
    EOF
    
  3. Run the following command to check Pod status and wait for Kafka and Zookeeper are all up and running.

    $ kubectl -n default get pod 
    NAME                                         READY   STATUS    RESTARTS   AGE
    my-cluster-entity-operator-f977bf457-s7ns2   3/3     Running   0          69m
    my-cluster-kafka-0                           2/2     Running   0          69m
    my-cluster-kafka-1                           2/2     Running   0          69m
    my-cluster-kafka-2                           2/2     Running   0          69m
    my-cluster-zookeeper-0                       1/1     Running   0          71m
    my-cluster-zookeeper-1                       1/1     Running   1          71m
    my-cluster-zookeeper-2                       1/1     Running   1          71m
    strimzi-cluster-operator-7d6cd6bdf7-9cf6t    1/1     Running   0          104m
    

    Run the following command to check the metadata of the Kafka cluster:

    kafkacat -L -b my-cluster-kafka-0.my-cluster-kafka-brokers.default.svc:9092,my-cluster-kafka-1.my-cluster-kafka-brokers.default.svc:9092,my-cluster-kafka-2.my-cluster-kafka-brokers.default.svc:9092
    

Step 2: Add Kafka as a Log Receiver

  1. Log in to KubeSphere as admin. Click Platform in the top left corner and select Cluster Management.

  2. If you have enabled the multi-cluster feature, you can select a specific cluster. If you have not enabled the feature, refer to the next step directly.

  3. On the Cluster Management page, go to Log Collections in Cluster Settings.

  4. Click Add Log Collector and select Kafka. Input the Kafka broker address and port as below, and then click OK to continue.

    my-cluster-kafka-0.my-cluster-kafka-brokers.default.svc 9092
    my-cluster-kafka-1.my-cluster-kafka-brokers.default.svc 9092
    my-cluster-kafka-2.my-cluster-kafka-brokers.default.svc 9092
    

    add-kafka

  5. Run the following commands to verify whether the Kafka cluster is receiving logs sent from Fluent Bit:

    # Start a util container
    kubectl run --rm utils -it --generator=run-pod/v1 --image arunvelsriram/utils bash
    # Install Kafkacat in the util container
    apt-get install kafkacat
    # Run the following command to consume log messages from kafka topic: my-topic
    kafkacat -C -b my-cluster-kafka-0.my-cluster-kafka-brokers.default.svc:9092,my-cluster-kafka-1.my-cluster-kafka-brokers.default.svc:9092,my-cluster-kafka-2.my-cluster-kafka-brokers.default.svc:9092 -t my-topic