kubectl出现报错如下：
"Failed to run kubelet" err="failed to run Kubelet: misconfiguration: kubelet cgroup driver: "systemd" is different from docker cgroup driver: "cgroupfs""
可如下解决：
# 启动指定驱动 eg:KUBELET_EXTRA_ARGS=--cgroup-driver=cgroupfs vi /etc/sysconfig/kubelet systemctl daemon-reload systemctl restart kubelet
注：官方建议使用systemd，此处docker使用的是cgroupfs，所以与docker统一了
