清理 rancher（k8s）集群机器

# ！！！下面这两个命令会删除机器上所有容器（请慎重！你可以手工挨个删除或修改一下命令过滤条件）
docker rm -f $(sudo docker ps -aq);
docker volume rm $(sudo docker volume ls -q);

rm -rf /etc/cni \
       /etc/kubernetes \
       /opt/cni \
       /opt/rke \
       /run/secrets/kubernetes.io \
       /run/calico \
       /run/flannel \
       /var/lib/calico \
       /var/lib/etcd \
       /var/lib/cni \
       /var/lib/kubelet \
       /var/lib/rancher/rke/log \
       /var/log/containers \
       /var/log/pods \
       /var/run/calico

for mount in $(mount | grep tmpfs | grep '/var/lib/kubelet' | awk '{ print $3 }') /var/lib/kubelet /var/lib/rancher; do umount $mount; done

rm -f /var/lib/containerd/io.containerd.metadata.v1.bolt/meta.db
sudo systemctl restart containerd
sudo systemctl restart docker

# 根据你的需要决定是否 reboot 重启机器，如果机器比较干净，最好重启一下