检查操作系统版本

cat /etc/redhat-release

主机名解析

vi /etc/hosts

192.168.56.200 master
192.168.56.201 node1
192.168.56.202 node2

时间同步

systemctl start chronyd
systemctl enable chronyd
date

禁用 iptables 和 firewalld 服务

systemctl stop firewalld
systemctl disable firewalld
systemctl stop iptables
systemctl disable iptables

禁用 selinux

vi /etc/selinux/config
SELINUX=disabled

禁用 swap 分区

vi /etc/fstab
# 注释掉 swap 分区一行

修改 linux 内核参数

vi /etc/sysctl.d/kubernetes.conf

net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1

# 重新加载
sysctl -p

# 加载网桥过滤模块
modprobe br_netfilter

# 查看网桥过滤模块是否加载成功
lsmod | grep br_netfilter

配置 ipvs 功能

yum install ipset ipvsadmin -y

cat <<EOF > /etc/sysconfig/modules/ipvs.modules
#! /bin/bash
modprobe -- ip_vs
modprobe -- ip_vs_rr
modprobe -- ip_vs_wrr
modprobe -- ip_vs_sh
modprobe -- nf_conntrack_ipv4
EOF

chmod +x /etc/sysconfig/modules/ipvs.modules

/bin/bash /etc/sysconfig/modules/ipvs.modules

lsmod | grep -e ip_vs -e nf_conntrack_ipv4

安装 Docker

wget https://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo -O /etc/yum.repos.d/docker-ce.repo

yum list docker-ce --showduplicates

yum install --setopt=obsoletes=0 docker-ce-18.06.3.ce-3.el7 -y

mkdir /etc/docker
cat <<EOF > /etc/docker/daemon.json
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "registry-mirrors": ["https://kn0t2bca.mirror.aliyuncs.com"]
}
EOF

systemctl restart docker
systemctl enable docker

安裝 Kubernetes 組件

vi /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

yum install --setopt=obsoletes=0 kubeadm-1.17.4-0 kubelet-1.17.4-0 kubectl-1.17.4-0 -y

vi /etc/sysconfig/kubelet

KUBELET_CGROUP_ARGS="--cgroup-driver=systemd"
KUBE_PROXY_MODE="ipvs"

systemctl enable kubelet

准备集群镜像

查看所需镜像
kubeadm config images list

# 替换镜像
images=(
  kube-apiserver:v1.17.4
  kube-controller-manager:v1.17.4
  kube-scheduler:v1.17.4
  kube-proxy:v1.17.4
  pause:3.1
  etcd:3.4.3-0
  coredns:1.6.5
)

for imageName in ${images[@]} ; do
  docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName
  docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName k8s.gcr.io/$imageName
  docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName
done

集群初始化

master 执行

# 创建集群
kubeadm init \
--kubernetes-version=v1.17.4 \
--pod-network-cidr=10.244.0.0/16 \
--service-cidr=10.96.0.0/12 \
--apiserver-advertise-address=192.168.56.200 \
--apiserver-cert-extra-sans=192.168.56.200

# 创建必要文件
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

安装网络插件

# 获取 fannel 配置文件
wget https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml

# 修改文件中 quay.io 仓库为 quay-mirror.qiniu.com

# 使用配置文件启动 fannel
kubectl apply -f kube-flannel.yml

# 稍等片刻，再次查看集群节点状态
kubectl get nodes