参考Kubnetes官方文档：https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/

1. 配置阿里云k8s的镜像包

#以下是配置阿里云的kubernetes镜像源包
# cat <<EOF > /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
EOF

2.安装k8s

#以下使安装kubernetes的组件
# yum install -y kubelet kubeadm kubectl --disableexcludes=kubernetes

#以下使设置开机启动和启动服务
# systemctl enable kubelet && systemctl start kubelet

3.启动路由转发

#以下使配置转发路由参数
# cat <<EOF >  /etc/sysctl.d/k8s.conf
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
net.ipv4.conf.all.forwarding = 1
EOF

# sysctl --system         #使参数生效

4。配置cgroup驱动程序和网易的镜像加速

# vi /etc/docker/daemon.json
{
"registry-mirrors": ["http://hub-mirror.c.163.com"],
"exec-opts": ["native.cgroupdriver=systemd"]
}

# systemctl daemon-reload

# systemctl restart docker

# systemctl restart kubelet

5.禁止交换分区 的使用内存

# swapoff -a    #临时禁止交换分区的使用内存

# free -m

6.编辑脚本pull和tag镜像（这里可以忽略）

# vi image_k8s.sh 

#!/bin/bash
images=(kube-proxy-amd64:v1.17.0 kube-scheduler-amd64:v1.17.0 kube-controller-manager-amd64:v1.17.0 kube-apiserver-amd64:v1.17.0 etcd-amd64:3.4.3-0  coredns:1.6.5 pause-amd64:3.1)
for imageName in ${images[@]} ; do
 docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/$imageName
done

# vi tag_k8s.sh 
#!/bin/bash
images=(kube-proxy:v1.17.0 kube-scheduler:v1.17.0 kube-controller-manager:v1.17.0 kube-apiserver:v1.17.0 etcd:3.4.3-0  coredns:1.6.5 pause:3.1)

images_old=(kube-proxy-amd64:v1.17.0 kube-scheduler-amd64:v1.17.0 kube-controller-manager-amd64:v1.17.0 kube-apiserver-amd64:v1.17.0 etcd-amd64:3.4.3-0  coredns:1.6.5 pause-amd64:3.1)

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

 done
done

# docker images
REPOSITORY                           TAG                 IMAGE ID            CREATED             SIZE
k8s.gcr.io/kube-controller-manager   v1.17.0             da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/kube-proxy                v1.17.0             da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/kube-scheduler            v1.17.0             da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/pause                     3.1                 da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/coredns                   1.6.5               da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/etcd                      3.4.3-0             da86e6ba6ca1        2 years ago         742kB
k8s.gcr.io/kube-apiserver            v1.17.0             da86e6ba6ca1        2 years ago         742kB

 7.初始化Master

# kubeadm init phase preflight  #初始化预检

#以下是初始化Master
# kubeadm init --image-repository registry.aliyuncs.com/google_containers --kubernetes-version v1.17.0 --apiserver-advertise-address 172.25.0.10  --pod-network-cidr=10.244.0.0/16  --cri-socket=/var/run/dockershim.sock  --control-plane-endpoint 172.25.0.10:6443

8.发生初始化错误，需要重新初始化设置

# kubeadm reset  #重新初始化设置

9.root用户要运行

# export KUBECONFIG=/etc/kubernetes/admin.conf

10.安装Pod网络

# kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/2140ac876ef134e0ed5af15c65e414cf26827915/Documentation/kube-flannel.yml

11.添加节点到集群

11-1.需要SSH服务

#以下是在Master节点操作
# ssh-keygen -t rsa -N ''
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Created directory '/root/.ssh'.
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:3rYOl3qZMG29Ifh9BkDVMOk/f0kcoB23OPA76RvdX/s root@controller
The key's randomart image is:
+---[RSA 2048]----+
|           .++   |
|          ...+.. |
|         . .= = .|
|          ...= o |
|        So o .= .|
|       .+.+.+++o.|
|        o===.=o++|
|         ==.o.+.*|
|        .oo  +..E|
+----[SHA256]-----+


# ssh-copy-id -i .ssh/id_rsa.pub  root@Master

# ssh-copy-id -i .ssh/id_rsa.pub  root@worker1

# ssh-copy-id -i .ssh/id_rsa.pub  root@worker2

11-2.在worker1和worker2注册到Cluster中

默认情况下，令牌会在24小时后过期。如果要在当前令牌过期后将节点加入集群，则可以通过在控制平面节点上运行以下命令来创建新令牌：

kubeadm token create

#以下是在Master查看密钥
[root@Master ~]#  kubeadm token list
TOKEN                     TTL         EXPIRES                     USAGES                   DESCRIPTION                                                EXTRA GROUPS
6vzl4q.u8jpoagms4p9rgc6   23h         2019-12-24T17:40:01+08:00   authentication,signing   The default bootstrap token generated by 'kubeadm init'.   system:bootstrappers:kubeadm:default-node-token

#以下是在Master查看哈希256密钥
[root@Master ~]# openssl x509 -pubkey -in /etc/kubernetes/pki/ca.crt | openssl rsa -pubin -outform der 2>/dev/null | \
>    openssl dgst -sha256 -hex | sed 's/^.* //'
679d5623bb141e8b83de3a1aae863974763463e774666a435a10e819ab82ab7f



#以下是在从节点加入集群
[root@worker1 ~]# kubeadm join 172.25.0.10:6443 --token  6vzl4q.u8jpoagms4p9rgc6 \
    --discovery-token-ca-cert-hash sha256:679d5623bb141e8b83de3a1aae863974763463e774666a435a10e819ab82ab7f 

[root@worker2 ~]# kubeadm join 172.25.0.10:6443 --token  6vzl4q.u8jpoagms4p9rgc6 \
    --discovery-token-ca-cert-hash sha256:679d5623bb141e8b83de3a1aae863974763463e774666a435a10e819ab82ab7f

11-3在Master节点查看

# kubectl get node
NAME         STATUS   ROLES    AGE   VERSION
worker1      Ready    <none>   39m   v1.17.0
Master       Ready    master   40m   v1.17.0
worker2      Ready    <none>   25m   v1.17.0

12.对worker节点添加roles标签

# kubectl label node worker1 node-role.kubernetes.io/worker=worker

# kubectl label node worker2 node-role.kubernetes.io/worker=worker

# kubectl get node
NAME         STATUS   ROLES            AGE   VERSION
worker1      Ready    worker           45m   v1.17.0
Master       Ready    master           46m   v1.17.0
worker2      Ready    worker           31m   v1.17.0