The connection to the server x.x.x.:6443 was refused - did you specify the right host or port? Kubernetes

Question

I've installed, Docker, Kubectl and kubeAdm. I want to create my device model and device CRDs (I'm following this guide. So, when I run the command :

kubectl create -f devices_v1alpha1_devicemodel.yaml

as a user I get the following out:

The connection to the server 10.0.0.68:6443 was refused - did you
specify the right host or port?

(I have added the permission for the user to access the .kube folder)

With netstat, I get :

> ubuntu@kubernetesmaster:~/src/github.com/kubeedge/kubeedge/build/crds/devices$
> sudo netstat -atunp    Active Internet connections (servers and
> established)                                                 Proto
> Recv-Q Send-Q Local Address           Foreign Address         State   
> PID/Program name      tcp        0      0 0.0.0.0:22             
> 0.0.0.0:*               LISTEN      1298/sshd             tcp        0    224 10.0.0.68:22            160.98.31.160:52503     ESTABLISHED
> 2061/sshd: ubuntu [   tcp6       0      0 :::22                   :::*
> LISTEN      1298/sshd             udp        0      0 0.0.0.0:68      
> 0.0.0.0:*                           910/dhclient          udp        0      0 10.0.0.68:123           0.0.0.0:*                          
> 1241/ntpd             udp        0      0 127.0.0.1:123          
> 0.0.0.0:*                           1241/ntpd             udp        0      0 0.0.0.0:123             0.0.0.0:*                          
> 1241/ntpd             udp6       0      0 fe80::f816:3eff:fe0:123 :::*
> 1241/ntpd             udp6       0      0 2001:620:5ca1:2f0:f:123 :::*
> 1241/ntpd             udp6       0      0 ::1:123                 :::*
> 1241/ntpd             udp6       0      0 :::123                  :::*
> 1241/ntpd

With lsof -i :

ubuntu@kubernetesmaster:~/src/github.com/kubeedge/kubeedge/build/crds/devices$ sudo lsof -i
COMMAND   PID   USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
dhclient  910   root    6u  IPv4  12765      0t0  UDP *:bootpc
ntpd     1241    ntp   16u  IPv6  15340      0t0  UDP *:ntp
ntpd     1241    ntp   17u  IPv4  15343      0t0  UDP *:ntp
ntpd     1241    ntp   18u  IPv4  15347      0t0  UDP localhost:ntp
ntpd     1241    ntp   19u  IPv4  15349      0t0  UDP 10.0.0.68:ntp
ntpd     1241    ntp   20u  IPv6  15351      0t0  UDP ip6-localhost:ntp
ntpd     1241    ntp   21u  IPv6  15353      0t0  UDP [2001:620:5ca1:2f0:f816:3eff:fe0a:874a]:ntp
ntpd     1241    ntp   22u  IPv6  15355      0t0  UDP [fe80::f816:3eff:fe0a:874a]:ntp
sshd     1298   root    3u  IPv4  18821      0t0  TCP *:ssh (LISTEN)
sshd     1298   root    4u  IPv6  18830      0t0  TCP *:ssh (LISTEN)
sshd     2061   root    3u  IPv4  18936      0t0  TCP 10.0.0.68:ssh->160.98.31.160:52503 (ESTABLISHED)
sshd     2124 ubuntu    3u  IPv4  18936      0t0  TCP 10.0.0.68:ssh->160.98.31.160:52503 (ESTABLISHED)

I've already tried this and:sudo swapoff -a

Answer 1

Please perform below steps on the master node. It works like charm.

1. sudo -i

2. swapoff -a

3. exit

4. strace -eopenat kubectl version

Answer 2

I am facing similar problem with following error while deploying the pod network into a cluster using flannel:

$ kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
The connection to the server 192.168.1.101:6443 was refused - did you specify the right host or port?

I performed below steps to solved the issue:

$ sudo systemctl stop kubelet
$ sudo systemctl start kubelet
$ strace -eopenat kubectl version

then apply the yml file

$ kubectl apply -f https://raw.githubusercontent.com/coreos/flannel/master/Documentation/kube-flannel.yml
podsecuritypolicy.policy/psp.flannel.unprivileged created
clusterrole.rbac.authorization.k8s.io/flannel created
clusterrolebinding.rbac.authorization.k8s.io/flannel created
serviceaccount/flannel created
configmap/kube-flannel-cfg created
daemonset.apps/kube-flannel-ds created

Answer 3

kubelet must be down. you need to check kubelet logs on the master and ensure api server is running and online. then only you should be able to deploy

Answer 4

I'll add another reason for this error that was the issue in my case.

I exported the wrong Kubeconfig file to shell and the error message was very accurate in that case - The endpoint for the API server was wrong (and of course other fields like the cluster name and the certificates - but the server endpoint is the first step in the chain).

Answer 5

I've encountered this problem and swapoff -a works for me though.

sudo -i
swapoff -a
exit
strace -eopenat kubectl version