4、Kubectl CLI 客户端

一、Kubectl CLI 简介

Kubectl 是Kubernetes集群的命令行工具，通过kubectl能够对集群本身进行管理，并能够在集群上进行容器化应用的安装部署。

官方网站：https://kubernetes.io/docs/tasks/tools/install-kubectl

https://kubernetes.io/docs/tasks/tools/install-kubectl-linux/

二、Kubectl CLI 安装

1、使用脚本安装 kubectl

curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl" && chmod +x kubectl && cp kubectl /usr/bin/
# =====================================国内备用 ===========================================
curl -fL "https://kinshy-generic.pkg.coding.net/south/study/kubectl?version=latest" -o kubectl && chmod +x kubectl && cp kubectl /usr/bin/


# 下载特定版本 kubectl

curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
sudo install -o root -g root -m 0755 kubectl /usr/bin/kubectl

sudo wget https://storage.googleapis.com/kubernetes-release/release/v1.15.2/bin/linux/amd64/kubectl
# 制作kubectl二进制可执行文件
sudo chmod +x ./kubectl
# 将二进制文件移动到PATH中
sudo mv ./kubectl /usr/local/bin/kubectl
# 测试以确保您安装的版本是最新的
kubectl version

2、使用本机包管理器安装 kubectl（推荐）

Kubernetes 官网文档参照 安装 kubectl 安装时，经常会失败，因为国内访问 google 的镜像仓库存在问题。

# 配置K8S的yum源
cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=http://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=0
repo_gpgcheck=0
gpgkey=http://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
       http://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
EOF
# 安装最新版本 kubectl
yum install -y kubectl
# 测试以确保您安装的版本是最新的
kubectl version

三、Kubectl CLI 配置

为了让 kubectl 能够查找和访问Kubernetes集群，它需要一个kubeconfig文件，该文件是在使用kube-up.sh或成功部署Minikube集群创建集群时自动创建的。默认情况下，kubectl配置位于~/.kube/config。

1、获取 kubectl config 文件

如果您参考 安装 Kubernetes 单Master节点 或 安装 Kubernetes 高可用 完成了 Kubernetes 安装，请在 k8s-master 节点上执行如下命令

cat ~/.kube/config

输出内容如下所示：

apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: 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
    server: https://apiserver.demo:6443
  name: kubernetes
contexts:
- context:
    cluster: kubernetes
    user: kubernetes-admin
  name: kubernetes-admin@kubernetes
current-context: kubernetes-admin@kubernetes
kind: Config
preferences: {}
users:
- name: kubernetes-admin
  user:
    client-certificate-data: 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
    client-key-data: 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

如果是通过Rancher 安装的K8s集群，可在界面看到该配置：

2、配置客户端 kubectl config 文件

在客户端电脑完成如下配置，即可远程管理 Kubernetes 集群

执行命令

vi ~/.kube/config

将 kubectl config 文件的内容粘贴进该文件并保存

配置 hosts

echo "x.x.x.x  apiserver.k8s" >> /etc/hosts

• 将 x.x.x.x 替换成 k8s-master 的实际 IP 地址
• 将 apiserver.k8s 替换成 kubectl config 文件中 clusters/cluster/server 中 URL 里 host 对应的部分

验证安装结果

执行命令

kubectl get nodes
kubectl get pods -n kube-system

参考资料

http://docs.kubernetes.org.cn/61.html
https://kuboard.cn/install/install-kubectl.html
https://kubernetes.io/docs/reference/kubectl/overview/
https://kubernetes.io/docs/tasks/tools/install-kubectl/