“kubectl get nodes” shows NotReady always even after giving the appropriate IP

Question

i am trying to setup a kubernetes cluster for testing purpose with a master and one minion. When i run the kubectl get nodes it always says NotReady. Following the configuration on minion in /etc/kubernetes/kubelet

KUBELET_ADDRESS="--address=0.0.0.0"
KUBELET_PORT="--port=10250"
KUBELET_HOSTNAME="--hostname-override=centos-minion"
KUBELET_API_SERVER="--api-servers=http://centos-master:8080"
KUBELET_ARGS=""

When kubelete service is started following logs could be seen

Mar 16 13:29:49 centos-minion kubelet: E0316 13:29:49.126595 53912 event.go:202] Unable to write event: 'Post http://centos-master:8080/api/v1/namespaces/default/events: dial tcp 10.143.219.12:8080: i/o timeout' (may retry after sleeping)

Mar 16 13:16:01 centos-minion kube-proxy: E0316 13:16:01.195731 53595 event.go:202] Unable to write event: 'Post http://localhost:8080/api/v1/namespaces/default/events: dial tcp [::1]:8080: getsockopt: connection refused' (may retry after sleeping)

Following is the config on master /etc/kubernetes/apiserver

KUBE_API_ADDRESS="--bind-address=0.0.0.0"
KUBE_API_PORT="--port=8080"
KUBELET_PORT="--kubelet-port=10250"
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"

/etc/kubernetes/config

KUBE_ETCD_SERVERS="--etcd-servers=http://centos-master:2379"
KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://centos-master:8080"

On master following processes are properly running

kube 5657 1 0 Mar15 ? 00:12:05 /usr/bin/kube-apiserver --logtostderr=true --v=0 --etcd-servers=http://centos-master:2379 --address=0.0.0.0 --port=8080 --kubelet-port=10250 --allow-privileged=false --service-cluster-ip-range=10.254.0.0/16

kube 5690 1 1 Mar15 ? 00:16:01 /usr/bin/kube-controller-manager --logtostderr=true --v=0 --master=http://centos-master:8080

kube 5723 1 0 Mar15 ? 00:02:23 /usr/bin/kube-scheduler --logtostderr=true --v=0 --master=http://centos-master:8080

So i still do not know what is missing.

Are you able to telnet master on port 8080 ? And what is IP of master ? — user2486495
Yes. I am able to ping the master and its reachable. IP of the master is 10.x.x.12 and this is also configured in /etc/hosts — Prashant
Try "telnet 10.x.x.12 8080" from minion and share the output. — user2486495
Test the api-server from the master itself. It looks like it did not start (or not start correct). — Norbert van Nobelen
apiserver seems to be fine kube 7511 1 0 Mar16 ? 00:07:56 /usr/bin/kube-apiserver --logtostderr=true --v=0 --etcd-servers=127.0.0.1:2379 --insecure-bind-address=0.0.0.0 --insecure-port=8080 --kubelet-port=10250 --allow-privileged=false --service-cluster-ip-range=10.254.0.0/16 kube 7545 1 1 Mar16 ? 00:10:17 /usr/bin/kube-controller-manager --logtostderr=true --v=0 --master=centos-master:8080 kube 7579 1 0 Mar16 ? 00:01:35 /usr/bin/kube-scheduler --logtostderr=true --v=0 --master=centos-master:8080 — Prashant

QiZ QiZ · Accepted Answer · 2017-09-06T17:30:42

I was having the same issue when I setting up the kubernetes with fedora following the steps on kubernetes.io. In the tutorial, it's commenting out KUBELET_ARGS="--cgroup-driver=systemd" in node's /etc/kubernetes/kubelet, if you uncomment it, you will see the node status become ready. Hope this help

“kubectl get nodes” shows NotReady always even after giving the appropriate IP

3 Answers