使用 Helm 包管理工具简化 Kubernetes 应用部署

Posted 2021-01-16 irving

当在 Kubernetes 中已经部署很多应用时，后续需要对每个应用的 yaml 文件进行维护操作，这个过程会变的很繁琐，我们可以使用 Helm 来简化这些工作。Helm 是 Kubernetes 的一个包管理工具，用来简化 Kubernetes 应用的部署和管理。

部署 Helm 客户端与服务端

部署客户端

在 github 上Helm Realese 下载最新的二进制文件

$ tar -zxvf helm-v2.11.0-linux-amd64.tar.gz
$ mv linux-amd64/helm /usr/local/bin/helm
$ helm help

部署服务端（tiller ）

$ helm init --upgrade --tiller-image sapcc/tiller:v2.11.0
Creating /root/.helm 
Creating /root/.helm/repository 
Creating /root/.helm/repository/cache 
Creating /root/.helm/repository/local 
Creating /root/.helm/plugins 
Creating /root/.helm/starters 
Creating /root/.helm/cache/archive 
Creating /root/.helm/repository/repositories.yaml 
Adding stable repo with URL: https://kubernetes-charts.storage.googleapis.com 
Adding local repo with URL: http://127.0.0.1:8879/charts 
$HELM_HOME has been configured at /root/.helm.

Tiller (the Helm server-side component) has been installed into your Kubernetes Cluster.

Please note: by default, Tiller is deployed with an insecure ‘allow unauthenticated users‘ policy.
To prevent this, run `helm init` with the --tiller-tls-verify flag.
For more information on securing your installation see: https://docs.helm.sh/using_helm/#securing-your-helm-installation
Happy Helming!

备注:在 DockerHub 上找到了同步的镜像 ：https://hub.docker.com/r/sapcc/tiller/ 。

查看

$ kubectl get pod -n kube-system -l app=helm
NAME                             READY   STATUS    RESTARTS   AGE
tiller-deploy-69c9dc58bd-jvzkr   1/1     Running   0          3m2s
$ helm version
Client: &version.Version{SemVer:"v2.11.0", GitCommit:"2e55dbe1fdb5fdb96b75ff144a339489417b146b", GitTreeState:"clean"}
Server: &version.Version{SemVer:"v2.11.0", GitCommit:"2e55dbe1fdb5fdb96b75ff144a339489417b146b", GitTreeState:"clean"}

配置 RBAC

$ vi rbac-config.yaml

apiVersion: v1
kind: ServiceAccount
metadata:
  name: tiller
  namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: tiller
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cluster-admin
subjects:
  - kind: ServiceAccount
    name: tiller
    namespace: kube-system

执行

$ kubectl create -f rbac-config.yaml
serviceaccount/tiller created
clusterrolebinding.rbac.authorization.k8s.io/tiller created
$ kubectl patch deploy --namespace kube-system tiller-deploy -p ‘{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}‘
deployment.extensions/tiller-deploy patched

备注：上述我们为 Tiller 管理员提供了对整个群集的访问权限，如果不需要授予 Tiller 集群管理员访问权限，可以指定 Role 和 RoleBinding 来将 Tiller 的范围限制为特定的 namespace 中，官方文档是新建一个 namespace 做的(https://docs.helm.sh/using_helm/#role-based-access-control) 。

REFER:

https://docs.helm.sh/using_helm/

https://github.com/helm/helm

https://docs.bitnami.com/kubernetes/how-to/configure-rbac-in-your-kubernetes-cluster/