1.检查centos发行版

查看centos版本

cat /etc/redhad-release

如果不是7.6，7.7，7.8直接升级centos

yum update -y kernel
rpm -q kernel
yum update

2.安装kubernetes准备工作

• 安装docker

# 添加repo
sudo yum install -y yum-utils
sudo yum-config-manager \
    --add-repo \
    https://download.docker.com/linux/centos/docker-ce.repo
#安装
sudo yum update -y
sudo yum install docker-ce docker-ce-cli containerd.io -y

修改/etc/docker/daemon.json —- 先配置好国内镜像，不然后面加入节点image pull不下来

{
   
  "debug": true,
  "experimental": false,
  "registry-mirrors": [
	"https://docker.mirrors.ustc.edu.cn",
    "https://registry.docker-cn.com"
  ]
}

添加到开机启动

sudo systemctl start docker
sudo systemctl enable docker

• 安装kubernetes

cat <<EOF > /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg
EOF

#将 SELinux 设置为 permissive 模式（相当于将其禁用）
setenforce 0
sed -i 's/^SELINUX=enforcing$/SELINUX=permissive/' /etc/selinux/config

yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes

systemctl enable --now kubelet

起动kubelet 失败是正常的，因为还没有对它init。

• 关swap

 swapoff -a && sed -i '/swap/d' /etc/fstab

• 设置iptable

cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
EOF
sysctl --system

3.使用kubeadm安装单机集群

• 配置使用参数

#本机ip
export MASTER_IP=192.168.88.201
#hostname
export APISERVER_NAME=apiserver.sh
export POD_SUBNET=10.100.0.1/16

#配置本地hosts，意思是：APISERVER_NAME与MASTER_IP相同
echo "${MASTER_IP} ${APISERVER_NAME}" >> /etc/hosts

• 执行安装

 curl -sSL https://kuboard.cn/install-script/v1.19.x/init_master.sh | sh -s 1.19.2

卸载与重装

• 如果安装失败需要重置：

kubeadm reset -f

• 删除k8s

yum remove kubelet-1.19.2 kubeadm-1.19.2 kubectl-1.19.2
yum remove kubelet kubeadm kubectl

#删除所有docker images文件
docker ps -q | xargs docker rm -f
docker images -q |xargs docker rmi -f
rm -rf /var/lib/docker

#处理minikube遗留
find /etc/ -type f |xargs grep 'minikube'
rm -rf /etc/systemd/system/kubelet.service.d

4.提升效率

命令自动补全
linux bash

yum install bash-completion -y
kubectl completion bash >/etc/bash_completion.d/kubectl
echo "source <(kubectl completion bash)" >> ~/.bashrc
source ~/.bashrc
#别名，可选
echo 'alias k=kubectl' >>~/.bashrc
echo 'complete -F __start_kubectl k' >>~/.bashrc

mac zsh

brew install  bash-completion
echo "source <(kubectl completion zsh)" >> ~/.zshrc
source ~/.zshrc
#别名，可选
echo 'alias k=kubectl' >>~/.zshrc
echo 'complete -F __start_kubectl k' >>~/.zshrc

设置参考：Install and Set Up kubectl

参考：使用 kubeadm 创建集群