部署一套单Master的K8s集群

# 配置要求

搭建K8S集群时，推荐在阿里云或腾讯云采购如下配置：（您也可以使用自己的虚拟机、私有云等您最容易获得的 Linux 环境）

• 至少2台 2核4G 的服务器
• 本文档中，CPU 必须为 x86 架构，暂时未适配 arm 架构的 CPU
• CentOS 7.8 或 CentOS Stream 8
• 本次部署使用CentOS 7.9

[root@demo-master ~]# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)

安装后的软件版本为

• Kubernetes v1.21.x
  • calico 3.17.1
  • nginx-ingress 1.9.1
• Containerd.io 1.4.3

# 检查 centos / hostname

[root@demo-master ~]# cat /etc/redhat-release
CentOS Linux release 7.9.2009 (Core)
[root@demo-master ~]# hostname
demo-master
[root@demo-master ~]# lscpu

 [root@demo-master ~]# hostnamectl status

 [root@demo-master ~]# ip route show
default via 192.168.178.2 dev ens33 proto static metric 100
192.168.178.0/24 dev ens33 proto kernel scope link src 192.168.178.90 metric 100
[root@demo-master ~]# ip address

kubelet使用的IP地址

• ip route show 命令中，可以知道机器的默认网卡，通常是 eth0，如 default via 172.21.0.23 dev eth0
• ip address 命令中，可显示默认网卡的 IP 地址，Kubernetes 将使用此 IP 地址与集群内的其他节点通信，如 172.17.216.80
• 所有节点上 Kubernetes 所使用的 IP 地址必须可以互通（无需 NAT 映射、无安全组或防火墙隔离）

-----------------------------------------每个个节点都必须部署的---------------------------------------------------------

export REGISTRY_MIRROR=https://registry.cn-hangzhou.aliyuncs.com

curl -sSL https://kuboard.cn/install-script/v1.21.x/install_kubelet.sh | sh -s 1.21.4

-----------------------节点初始化脚本install_kubelet.sh（安装 containerd）-------------------------------------

#!/bin/bash

# 在 master 节点和 worker 节点都要执行

# 安装 containerd
# 参考文档如下
# https://kubernetes.io/docs/setup/production-environment/container-runtimes/#containerd

cat <<EOF | sudo tee /etc/modules-load.d/containerd.conf
overlay
br_netfilter
EOF

sudo modprobe overlay
sudo modprobe br_netfilter

# Setup required sysctl params, these persist across reboots.
cat <<EOF | sudo tee /etc/sysctl.d/99-kubernetes-cri.conf
net.bridge.bridge-nf-call-iptables  = 1
net.ipv4.ip_forward                 = 1
net.bridge.bridge-nf-call-ip6tables = 1
EOF

# Apply sysctl params without reboot
sysctl --system

# 卸载旧版本
yum remove -y containerd.io

# 设置 yum repository
yum install -y yum-utils device-mapper-persistent-data lvm2
yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo

# 安装 containerd
yum install -y containerd.io-1.4.3

mkdir -p /etc/containerd
containerd config default > /etc/containerd/config.toml

sed -i "s#k8s.gcr.io#registry.aliyuncs.com/k8sxio#g"  /etc/containerd/config.toml
sed -i '/containerd.runtimes.runc.options/a            SystemdCgroup = true' /etc/containerd/config.toml
sed -i "s#https://registry-1.docker.io#${REGISTRY_MIRROR}#g"  /etc/containerd/config.toml


systemctl daemon-reload
systemctl enable containerd
systemctl restart containerd


# 安装 nfs-utils
# 必须先安装 nfs-utils 才能挂载 nfs 网络存储
yum install -y nfs-utils
yum install -y wget

# 关闭 防火墙
systemctl stop firewalld
systemctl disable firewalld

# 关闭 SeLinux
setenforce 0
sed -i "s/SELINUX=enforcing/SELINUX=disabled/g" /etc/selinux/config

# 关闭 swap
swapoff -a
yes | cp /etc/fstab /etc/fstab_bak
cat /etc/fstab_bak |grep -v swap > /etc/fstab

# 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

# 卸载旧版本
yum remove -y kubelet kubeadm kubectl

# 安装kubelet、kubeadm、kubectl
# 将 ${1} 替换为 kubernetes 版本号，例如 1.20.1
yum install -y kubelet-${1} kubeadm-${1} kubectl-${1}

crictl config runtime-endpoint /run/containerd/containerd.sock

# 重启 docker，并启动 kubelet
systemctl daemon-reload
systemctl enable kubelet && systemctl start kubelet

containerd --version
kubelet --version
------------------------------------------------------------------

------------------------------快速安装初始化：--------------------------------------------------------
export MASTER_IP=192.168.178.90
export APISERVER_NAME=apiserver.demo
export POD_SUBNET=10.100.0.0/16
echo "${MASTER_IP}    ${APISERVER_NAME}" >> /etc/hosts
curl -sSL https://kuboard.cn/install-script/v1.21.x/init_master.sh | sh -s 1.21.4

----------------------init_master.sh详细内容：----------------------------------------

 

#!/bin/bash

# 只在 master 节点执行

# 脚本出错时终止执行
set -e

if [ ${#POD_SUBNET} -eq 0 ] || [ ${#APISERVER_NAME} -eq 0 ]; then
  echo -e "33[31;1m请确保您已经设置了环境变量 POD_SUBNET 和 APISERVER_NAME 33[0m"
  echo 当前POD_SUBNET=$POD_SUBNET
  echo 当前APISERVER_NAME=$APISERVER_NAME
  exit 1
fi


# 查看完整配置选项 https://godoc.org/k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta2
rm -f ./kubeadm-config.yaml
cat <<EOF > ./kubeadm-config.yaml
---
apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration
kubernetesVersion: v${1}
imageRepository: registry.aliyuncs.com/k8sxio
controlPlaneEndpoint: "${APISERVER_NAME}:6443"
networking:
  serviceSubnet: "10.96.0.0/16"
  podSubnet: "${POD_SUBNET}"
  dnsDomain: "cluster.local"
dns:
  type: CoreDNS
  imageRepository: swr.cn-east-2.myhuaweicloud.com${2}
  imageTag: 1.8.0

---
apiVersion: kubelet.config.k8s.io/v1beta1
kind: KubeletConfiguration
cgroupDriver: systemd
EOF

# kubeadm init
# 根据您服务器网速的情况，您需要等候 3 - 10 分钟
echo ""
echo "抓取镜像，请稍候..."
kubeadm config images pull --config=kubeadm-config.yaml
echo ""
echo "初始化 Master 节点"
kubeadm init --config=kubeadm-config.yaml --upload-certs

# 配置 kubectl
rm -rf /root/.kube/
mkdir /root/.kube/
cp -i /etc/kubernetes/admin.conf /root/.kube/config
------------------------------------------------------------------------------------------------------------