操作系統：CentOS 7
(1)关闭防火墙
systemctl disable firewalld
systemctl stop firewalld
(2)安装etcd和kubernetes软件（会自动安装docker）
yum install -y etcd kubernetes
(3) kubernetes apiserver配置文件为/etc/kubernetes/apiserver，
把--admission-control参数中的ServiceAccount删除
把KUBE_API_ADDRESS修改成 KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
(4)按顺序启动所有服务
systemctl start etcd
systemctl start docker
systemctl start kube-apiserver
systemctl start kube-controller-manager
systemctl start kube-scheduler
systemctl start kubelet
systemctl start kube-proxy