1.检查是否关闭了 SELinux 和 iptables

#检查 selinux
 getenforce
 #永久修改 selinux
 sed 's/SELINUX=enforcing/SELINUX=disabled/' -i /etc/selinux/config
 #立即修改 selinux
 setenforce 0
 #关闭防火墙, 禁止防火墙自启动
 systemctl stop firewalld; systemctl disable firewalld

2.关闭 swap ,目前 Kubernetes 和 Docker 尚不支持内存 swap 空间的隔离机制

#临时关闭，立即生效
 swapoff -a
#永久关闭
 sed -i '/swap/ s/^/#/' /etc/fstab
#检查是否生效
 free -m

3.安装docker

#step 1: 安装GPG证书
    rpm --import http://mirrors.aliyun.com/docker-ce/linux/centos/gpg
#step 2:安装需要的软件包
    yum install -y yum-utils device-mapper-persistent-data lvm2
#step 3:下载yum源
    yum-config-manager --add-repo http://mirrors.aliyun.com/docker-ce/linux/centos/docker-ce.repo
#step 4:查看可安装的docker-ce
    yum list docker-ce.x86_64 --showduplicates | sort -r
#step 5:安装指定的docker-ce版本
    yum -y install docker-ce-18.09.9
    systemctl start docker
    systemctl enable docker

4.安装k8s

#step 1: GPG证书
    rpm --import  https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg
#step 2:导入镜像源
    cat /etc/yum.repos.d/kubernetes.repo
[kubernetes]
name=Kubernetes
baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg
#step 3:安装指定版本kubeadm,kubelet,kubectl
    yum install  kubeadm-1.15.5-0 kubelet-1.15.5-0 kubectl-1.15.5-0

step 4:初始化master

cat >init.yml<<-EOF
apiVersion: kubeadm.k8s.io/v1beta2
kind: ClusterConfiguration
clusterName: kubernetes
imageRepository: registry.aliyuncs.com/google_containers
 # curl https://storage.googleapis.com/kubernetes-release/release/stable-1.txt 查看当前最新版本.
 # 必须小于等于 kubeadm 版本,  如想要升级需要先升级 kubeadm
kubernetesVersion: v1.15.5
apiServer:
  extraArgs:
    service-node-port-range: 80-32767
    cloud-provider: external
  extraVolumes:
  - hostPath: /etc/localtime
    mountPath: /etc/localtime
    name: localtime
  - hostPath: /etc/kubernetes
    mountPath: /etc/kubernetes
    name: etc-kubernetes-fs
controllerManager:
  extraArgs:
    cloud-provider: external
  extraVolumes:
  - hostPath: /etc/localtime
    mountPath: /etc/localtime
    name: localtime
scheduler:
  extraVolumes:
  - hostPath: /etc/localtime
    mountPath: /etc/localtime
    name: localtime
networking:
  dnsDomain: cluster.local
  podSubnet: 10.233.0.0/16
EOF
#初始化
kubeadm init --config init.yml

5.配置kubectl

 mkdir -p $HOME/.kube
 sudo cp /etc/kubernetes/admin.conf $HOME/.kube/config
 sudo chown $(id -u):$(id -g) $HOME/.kube/config
 # 移除 master 节点的污点
 kubectl taint nodes k8s-master node-role.kubernetes.io/master:NoSchedule-
 # kubectl 自动补全
 echo 'source <(kubectl completion bash)' >> ~/.bashrc
 # 重启 shell
 exec $SHELL -l

5.安装calico网络

#下载 Calico 配置文件
  curl https://docs.projectcalico.org/v3.9/manifests/calico-etcd.yaml -O

#step 1:修改etcd配置

 # 修改网络配置
 POD_CIDR=`grep 'cluster-cidr' /etc/kubernetes/manifests/kube-controller-manager.yaml | awk -F= '{print $2}'`
 sed -i -e "s?192.168.0.0/16?$POD_CIDR?g" calico-etcd.yaml

 # 修改证书
 sed -i 's/# \(etcd-.*\)/\1/' calico-etcd.yaml
 etcd_key=$(cat /etc/kubernetes/pki/etcd/peer.key | base64 -w 0)
 etcd_crt=$(cat /etc/kubernetes/pki/etcd/peer.crt | base64 -w 0)
 etcd_ca=$(cat /etc/kubernetes/pki/etcd/ca.crt | base64 -w 0)
 sed -i -e 's/\(etcd-key: \).*/\1'$etcd_key'/' \
     -e 's/\(etcd-cert: \).*/\1'$etcd_crt'/' \
     -e 's/\(etcd-ca: \).*/\1'$etcd_ca'/' calico-etcd.yaml

 # 修改 etcd 地址
 ETCD=$(grep 'advertise-client-urls' /etc/kubernetes/manifests/etcd.yaml | awk -F= '{print $2}')
 sed -i -e 's@\(etcd_endpoints: \).*@\1"'$ETCD'"@' \
     -e 's/\(etcd_.*:\).*#/\1/' \
     -e 's/replicas: 1/replicas: 2/' calico-etcd.yaml

 # 指定探测网卡
 sed '/autodetect/a\            - name: IP_AUTODETECTION_METHOD\n              value: "interface=eth0"' -i calico-etcd.yaml

step 2:开始创建calico

kubectl apply -f calico-etcd.yaml