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

kubernetes kubelet
Prashant picture Prashant · Mar 16, 2017 · Viewed 9.2k times · Source

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.

Answer

QiZ picture QiZ · Sep 6, 2017

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

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