Currently I have one VM for kubernetes master (k8s-server), second for worker node(node-server). I need to specify a rule how this 2 server communicate each other. Through which ports should k8s-server have access to node-server and vice versa?
Strictly speaking Kubernetes makes use of the following ports, depending on your topology and configuration:
Kubelet
- healthz, default tcp:10248
- kubelet, default tcp:10250
- readonly, default tcp:10255
Kube-proxy
- healthz, default tcp:10256
- metrics, default tcp:10249
- proxy-port-range, default is randomly chosen tcp range
Api-server
- secure-port, default tcp:6443
- service-node-port-range, default tcp:30000-32767
Controller-manager
- secure-port, default tcp:10257
Kube-scheduler
- port, default tcp:10251
- secure port, default tcp:10259
Cloud-controller-manager
- secure port, default tcp:10258
Etcd
- port, default tcp:2379-2380However for your particular setup, I believe the following should suffice:
Master -> Kubelet
- kubelet-port, default 10250
- kubelet-readonly, default 10255
- service-node-port-range, default 30000-32767
Kubelet -> Master
- apiserver-secure-port, default 6443
- etcd-port, default 2379
- kubelet-port, default 10250Hope this helps.