節點服務有些預設 port ，如果想要服務能順利運行，請確保以下 port 可被訪問
Master Node
Protocol | Direction | Port Range | Purpose | Used By |
TCP | Inbound | 6443 | Kubernetes API server | All |
TCP | Inbound | 2379-2380 | etcd server client API | kube-apiserver, etcd |
TCP | Inbound | 10250 | Kubelet API | Self, Control plane |
TCP | Inbound | 10259 | kube-scheduler | Self |
TCP | Inbound | 10257 | kube-controller-manager | Self |
Worker Node
Protocol | Direction | Port Range | Purpose | Used By |
TCP | Inbound | 10250 | Kubelet API | Self, Control plane |
TCP | Inbound | 10256 | kube-proxy | Self, Load balancers |
TCP | Inbound | 30000-32767 | NodePort Services† | All |