基础信息：

Helm v3.12.3

Kubernetes v1.28.0

Containerd.io 1.6.22

以下为练习使用helm来安装、升级、回滚、卸载zookeeper的过程，供参考。

1、helm添加BitNami仓库

helm repo add bitnami https://charts.bitnami.com/bitnami

zhangzk@k8smaster:~$ helm repo add bitnami https://charts.bitnami.com/bitnami
"bitnami" has been added to your repositories

2、查看zookeeper的chart

  helm search repo zookeeper

zhangzk@k8smaster:~$ helm search repo zookeeper
NAME                            CHART VERSION   APP VERSION     DESCRIPTION                                       
bitnami/zookeeper               12.1.0          3.9.0           Apache ZooKeeper provides a reliable, centraliz...
bitnami/dataplatform-bp2        12.0.5          1.0.1           DEPRECATED This Helm chart can be used for the ...
bitnami/kafka                   25.1.0          3.5.1           Apache Kafka is a distributed streaming platfor...
bitnami/schema-registry         13.1.0          7.4.1           Confluent Schema Registry provides a RESTful in...
bitnami/solr                    8.0.0           9.3.0           Apache Solr is an extremely powerful, open sour...

3、拉取chart到本地

  helm pull bitnami/zookeeper

zhangzk@k8smaster:~/helm$ helm pull bitnami/zookeeper
zhangzk@k8smaster:~/helm$ ll
total 52
drwxrwxr-x 2 zhangzk zhangzk  4096 Aug 25 10:17 ./
drwxr-x--- 8 zhangzk zhangzk  4096 Aug 25 10:17 ../
-rw-r--r-- 1 zhangzk zhangzk 42792 Aug 25 10:17 zookeeper-12.1.0.tgz

4、修改values.yaml

  解压缩zookeeper-12.1.0.tgz

zhangzk@k8smaster:~/helm$ tar -zxvf zookeeper-12.1.0.tgz 
zhangzk@k8smaster:~/helm$ cd zookeeper
zhangzk@k8smaster:~/helm/zookeeper$ ll
total 124
drwxrwxr-x 4 zhangzk zhangzk  4096 Aug 25 10:18 ./
drwxrwxr-x 3 zhangzk zhangzk  4096 Aug 25 10:18 ../
-rw-r--r-- 1 zhangzk zhangzk   333 Aug 22 22:43 .helmignore
-rw-r--r-- 1 zhangzk zhangzk   226 Aug 22 22:43 Chart.lock
-rw-r--r-- 1 zhangzk zhangzk   845 Aug 22 22:43 Chart.yaml
-rw-r--r-- 1 zhangzk zhangzk 60180 Aug 22 22:43 README.md
drwxrwxr-x 3 zhangzk zhangzk  4096 Aug 25 10:18 charts/
drwxrwxr-x 2 zhangzk zhangzk  4096 Aug 25 10:18 templates/
-rw-r--r-- 1 zhangzk zhangzk 36205 Aug 22 22:43 values.yaml

修改values.yaml文件

修改点1：关闭持久化数据

## Enable persistence using Persistent Volume Claims
## ref: https://kubernetes.io/docs/user-guide/persistent-volumes/
##
persistence:## @param persistence.enabled Enable ZooKeeper data persistence using PVC. If false, use emptyDir##enabled: false

修改点2：修改为3份副本

## @param replicaCount Number of ZooKeeper nodes
##
replicaCount: 3

5、helm安装zookeeper到public-service命名空间

   kubectl create ns public-service

  helm install zookeeper -n public-service .

zhangzk@k8smaster:~/helm/zookeeper$ kubectl create ns public-service
namespace/public-service created
zhangzk@k8smaster:~/helm/zookeeper$ helm install zookeeper -n public-service .
NAME: zookeeper
LAST DEPLOYED: Fri Aug 25 10:39:05 2023
NAMESPACE: public-service
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
CHART NAME: zookeeper
CHART VERSION: 12.1.0
APP VERSION: 3.9.0** Please be patient while the chart is being deployed **ZooKeeper can be accessed via port 2181 on the following DNS name from within your cluster:zookeeper.public-service.svc.cluster.localTo connect to your ZooKeeper server run the following commands:export POD_NAME=$(kubectl get pods --namespace public-service -l "app.kubernetes.io/name=zookeeper,app.kubernetes.io/instance=zookeeper,app.kubernetes.io/component=zookeeper" -o jsonpath="{.items[0].metadata.name}")kubectl exec -it $POD_NAME -- zkCli.shTo connect to your ZooKeeper server from outside the cluster execute the following commands:kubectl port-forward --namespace public-service svc/zookeeper 2181:2181 &zkCli.sh 127.0.0.1:2181

6、查看Pod的状态

   kubectl get po -n public-service

zhangzk@k8smaster:~/helm/zookeeper$ kubectl get po -n public-service
NAME          READY   STATUS    RESTARTS   AGE
zookeeper-0   1/1     Running   0          102m
zookeeper-1   1/1     Running   0          102m
zookeeper-2   1/1     Running   0          102m

7、查看节点状态

kubectl exec zookeeper-0 -n public-service /opt/bitnami/zookeeper/bin/zkServer.sh status

zhangzk@k8smaster:~/helm/zookeeper$ kubectl exec zookeeper-0 -n public-service  /opt/bitnami/zookeeper/bin/zkServer.sh status
kubectl exec [POD] [COMMAND] is DEPRECATED and will be removed in a future version. Use kubectl exec [POD] -- [COMMAND] instead.
/opt/bitnami/java/bin/java
ZooKeeper JMX enabled by default
Using config: /opt/bitnami/zookeeper/bin/../conf/zoo.cfg
Client port found: 2181. Client address: localhost. Client SSL: false.
Mode: follower

8、升级版本 upgrade

修改 values.yaml文件replicaCount 为1并且保存

## @param replicaCount Number of ZooKeeper nodes
##
replicaCount: 1

  再执行如下命令：helm upgrade -n public-service zookeeper .

zhangzk@k8smaster:~/helm/zookeeper$ helm upgrade -n public-service zookeeper .
Release "zookeeper" has been upgraded. Happy Helming!
NAME: zookeeper
LAST DEPLOYED: Fri Aug 25 14:40:05 2023
NAMESPACE: public-service
STATUS: deployed
REVISION: 2
TEST SUITE: None
NOTES:
CHART NAME: zookeeper
CHART VERSION: 12.1.0
APP VERSION: 3.9.0** Please be patient while the chart is being deployed **ZooKeeper can be accessed via port 2181 on the following DNS name from within your cluster:zookeeper.public-service.svc.cluster.localTo connect to your ZooKeeper server run the following commands:export POD_NAME=$(kubectl get pods --namespace public-service -l "app.kubernetes.io/name=zookeeper,app.kubernetes.io/instance=zookeeper,app.kubernetes.io/component=zookeeper" -o jsonpath="{.items[0].metadata.name}")kubectl exec -it $POD_NAME -- zkCli.shTo connect to your ZooKeeper server from outside the cluster execute the following commands:kubectl port-forward --namespace public-service svc/zookeeper 2181:2181 &zkCli.sh 127.0.0.1:2181

再次查看pod发现只有一个pod了： kubectl get po -n public-service

zhangzk@k8smaster:~/helm/zookeeper$ kubectl get po -n public-service
NAME          READY   STATUS    RESTARTS   AGE
zookeeper-0   1/1     Running   0          20s

9、回滚版本

1）查看发布历史 ： helm history zookeeper -n public-service

zhangzk@k8smaster:~/helm/zookeeper$ helm history zookeeper -n public-service
REVISION        UPDATED                         STATUS          CHART                   APP VERSION     DESCRIPTION     
1               Fri Aug 25 12:40:59 2023        superseded      zookeeper-12.1.0        3.9.0           Install complete
2               Fri Aug 25 14:40:05 2023        deployed        zookeeper-12.1.0        3.9.0           Upgrade complete

2）回滚到版本1： helm rollback zookeeper 1 -n public-service

hangzk@k8smaster:~/helm/zookeeper$ helm rollback zookeeper 1 -n public-service
Rollback was a success! Happy Helming!

3）再次查看pod发现又变更为3个pod了: kubectl get po -n public-service

zhangzk@k8smaster:~/helm/zookeeper$ kubectl get po -n public-service
NAME          READY   STATUS    RESTARTS   AGE
zookeeper-0   1/1     Running   0          30m
zookeeper-1   1/1     Running   0          31m
zookeeper-2   1/1     Running   0          31m

10、卸载release

  helm uninstall zookeeper -n public-service

zhangzk@k8smaster:~/helm/zookeeper$ helm uninstall zookeeper -n public-service
release "zookeeper" uninstalled