使用helm在k8s上部署kafka

https://blog.frognew.com/2019/07/use-helm-install-kafka-on-k8s.html

1.配置helm chart repo

kafka的helm chart还在孵化当中，使用前需要添加incubator的repo：helm repo add incubator http://storage.googleapis.com/kubernetes-charts-incubator。

肉身在国内需要设置azure提供的镜像库地址:

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helm repo add stable http://mirror.azure.cn/kubernetes/charts helm repo add incubator http://mirror.azure.cn/kubernetes/charts-incubator helm repo list NAME URL stable http://mirror.azure.cn/kubernetes/charts local http://127.0.0.1:8879/charts incubator http://mirror.azure.cn/kubernetes/charts-incubator

2.创建Kafka和Zookeeper的Local PV

2.1 创建Kafka的Local PV

这里的部署环境是本地的测试环境，存储选择Local Persistence Volumes。首先，在k8s集群上创建本地存储的StorageClass local-storage.yaml：

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apiVersion: storage.k8s.io/v1 kind: StorageClass metadata: name: local-storage provisioner: kubernetes.io/no-provisioner volumeBindingMode: WaitForFirstConsumer reclaimPolicy: Retain

1 2	kubectl apply -f local-storage.yaml storageclass.storage.k8s.io/local-storage created

这里要在node1、node2这两个k8s节点上部署3个kafka的broker节点，因此先在node1、node2上创建这3个kafka broker节点的Local PV kafka-local-pv.yaml:

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apiVersion: v1 kind: PersistentVolume metadata: name: datadir-kafka-0 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/data-0 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node1 --- apiVersion: v1 kind: PersistentVolume metadata: name: datadir-kafka-1 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/data-1 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node2 --- apiVersion: v1 kind: PersistentVolume metadata: name: datadir-kafka-2 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/data-2 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node2

1	kubectl apply -f kafka-local-pv.yaml

根据上面创建的local pv，在node1上创建目录/home/kafka/data-0，在node2上创建目录/home/kafka/data-1和/home/kafka/data-2。

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# node1 mkdir -p /home/kafka/data-0 # node2 mkdir -p /home/kafka/data-1 mkdir -p /home/kafka/data-2

2.2 创建Zookeeper的Local PV

这里要在node1、node2这两个k8s节点上部署3个zookeeper节点，因此先在node1、node2上创建这3个zookeeper节点的Local PV zookeeper-local-pv.yaml:

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apiVersion: v1 kind: PersistentVolume metadata: name: data-kafka-zookeeper-0 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/zkdata-0 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node1 --- apiVersion: v1 kind: PersistentVolume metadata: name: data-kafka-zookeeper-1 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/zkdata-1 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node2 --- apiVersion: v1 kind: PersistentVolume metadata: name: data-kafka-zookeeper-2 spec: capacity: storage: 5Gi accessModes: - ReadWriteOnce persistentVolumeReclaimPolicy: Retain storageClassName: local-storage local: path: /home/kafka/zkdata-2 nodeAffinity: required: nodeSelectorTerms: - matchExpressions: - key: kubernetes.io/hostname operator: In values: - node2

1	kubectl apply -f zookeeper-local-pv.yaml

根据上面创建的local pv，在node1上创建目录/home/kafka/zkdata-0，在node2上创建目录/home/kafka/zkdata-1和/home/kafka/zkdata-2。

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# node1 mkdir -p /home/kafka/zkdata-0 # node2 mkdir -p /home/kafka/zkdata-1 mkdir -p /home/kafka/zkdata-2

3.部署Kafka

编写kafka chart的vaule文件kafka-values.yaml:

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replicas: 3 tolerations: - key: node-role.kubernetes.io/master operator: Exists effect: NoSchedule - key: node-role.kubernetes.io/master operator: Exists effect: PreferNoSchedule persistence: storageClass: local-storage size: 5Gi zookeeper: persistence: enabled: true storageClass: local-storage size: 5Gi replicaCount: 3 image: repository: gcr.azk8s.cn/google_samples/k8szk tolerations: - key: node-role.kubernetes.io/master operator: Exists effect: NoSchedule - key: node-role.kubernetes.io/master operator: Exists effect: PreferNoSchedule

• 安装过程需要使用到gcr.io/google_samples/k8szk:v3等docker镜像，切换成使用azure的GCR Proxy Cache：gcr.azk8s.cn。

  1	helm install --name kafka --namespace kafka -f kafka-values.yaml incubator/kafka

最后需要确认所有的pod都处于running状态:

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kubectl get pod -n kafka -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES kafka-0 1/1 Running 0 12m 10.244.0.61 node1 <none> <none> kafka-1 1/1 Running 0 6m3s 10.244.1.12 node2 <none> <none> kafka-2 1/1 Running 0 2m26s 10.244.1.13 node2 <none> <none> kafka-zookeeper-0 1/1 Running 0 12m 10.244.1.9 node2 <none> <none> kafka-zookeeper-1 1/1 Running 0 11m 10.244.1.10 node2 <none> <none> kafka-zookeeper-2 1/1 Running 0 11m 10.244.1.11 node2 <none> <none> kubectl get statefulset -n kafka NAME READY AGE kafka 3/3 22m kafka-zookeeper 3/3 22m kubectl get service -n kafka NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kafka ClusterIP 10.102.8.192 <none> 9092/TCP 31m kafka-headless ClusterIP None <none> 9092/TCP 31m kafka-zookeeper ClusterIP 10.110.43.203 <none> 2181/TCP 31m kafka-zookeeper-headless ClusterIP None <none> 2181/TCP,3888/TCP,2888/TCP 31m

可以看到当前kafka的helm chart，采用StatefulSet的形式部署了kafka和zookeeper，而我们通过Local PV的形式，将kafka-0调度到node1上，将kafka-1和kafka-2调度到node2上。

4.安装后的测试

在k8s集群内运行下面的客户端Pod，访问kafka broker进行测试：

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apiVersion: v1 kind: Pod metadata: name: testclient namespace: kafka spec: containers: - name: kafka image: confluentinc/cp-kafka:5.0.1 command: - sh - -c - "exec tail -f /dev/null"

创建并进入testclient容器内：

1 2	kubectl apply -f testclient.yaml kubectl -n kafka exec testclient -it sh

查看kafka相关命令：

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ls /usr/bin/ | grep kafka kafka-acls kafka-broker-api-versions kafka-configs kafka-console-consumer kafka-console-producer kafka-consumer-groups kafka-consumer-perf-test kafka-delegation-tokens kafka-delete-records kafka-dump-log kafka-log-dirs kafka-mirror-maker kafka-preferred-replica-election kafka-producer-perf-test kafka-reassign-partitions kafka-replica-verification kafka-run-class kafka-server-start kafka-server-stop kafka-streams-application-reset kafka-topics kafka-verifiable-consumer kafka-verifiable-producer

创建一个Topic test1：

1	kafka-topics --zookeeper kafka-zookeeper:2181 --topic test1 --create --partitions 1 --replication-factor 1

查看的Topic：

1 2	kafka-topics --zookeeper kafka-zookeeper:2181 --list test1

5.总结

当前基于Helm官方仓库的chartincubator/kafka在k8s上部署的kafka，使用的镜像是confluentinc/cp-kafka:5.0.1。 即部署的是Confluent公司提供的kafka版本。Confluent Platform Kafka(简称CP Kafka)提供了一些Apache Kafka没有的高级特性，例如跨数据中心备份、Schema注册中心以及集群监控工具等。CP Kafka目前分为免费版本和企业版两种，免费版除了Apache Kafka的标准组件外还包含Schema注册中心和Rest Proxy。

Confluent Platform and Apache Kafka Compatibility中给出了Confluent Kafka和Apache Kafka的版本对应关系，可以看出这里安装的cp 5.0.1对应Apache Kafka的2.0.x。

进入一个broker容器中，查看：

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ls /usr/share/java/kafka | grep kafka kafka-clients-2.0.1-cp1.jar kafka-log4j-appender-2.0.1-cp1.jar kafka-streams-2.0.1-cp1.jar kafka-streams-examples-2.0.1-cp1.jar kafka-streams-scala_2.11-2.0.1-cp1.jar kafka-streams-test-utils-2.0.1-cp1.jar kafka-tools-2.0.1-cp1.jar kafka.jar kafka_2.11-2.0.1-cp1-javadoc.jar kafka_2.11-2.0.1-cp1-scaladoc.jar kafka_2.11-2.0.1-cp1-sources.jar kafka_2.11-2.0.1-cp1-test-sources.jar kafka_2.11-2.0.1-cp1-test.jar kafka_2.11-2.0.1-cp1.jar

可以看到对应apache kafka的版本号是2.11-2.0.1，前面2.11是Scala编译器的版本，Kafka的服务器端代码是使用Scala语言开发的，后边2.0.1是Kafka的版本。 即CP Kafka 5.0.1是基于Apache Kafka 2.0.1的。