The connection to the server 10.0.x.x:6443 was refused after restarting the VM where kubernetes master was installed using kubeadm

The problem is that if I stop the machine and restart it the master node seems to be down

• Since it was kubeadm installation that worked properly before restarts, seems like Env var is missing after restart. Try to run this before kubectl get nodes:

  export KUBECONFIG=/etc/kubernetes/admin.conf

  If it starts normally, then you need to make sure that KUBECONFIG environment variable is properly configured upon restart either adding it to .bashrc or similar...

Edited:

Why? How can I fix it so that it starts without having to input that?

• Ah, swap file is teasing you. By default kubelet will not start if swap is enabled. You have two options:

  • Remove swap: That's easy, just disable it as you already listed but make it permanent by commenting swap line in /etc/fstab file. Add # before line creating swap mount point and next time you restart you won't have it.

  • Allow kubelet to run with swap enabled: I know, not recommended by documentation, but if you like to live dangerous, you can add/edit in /etc/systemd/system/kubelet.service.d/10-kubeadm.conf following line:

    Environment="KUBELET_EXTRA_ARGS=--fail-swap-on=false"

    and next restart you will be able to run kubelet with swap enabled.

I got my problem fixed by clearing some space on the HDD. It seems that the space is low. Then, I restarted the server and it fixed my problem.

I encountered a similar issue where the kubectl commands are working in my master node but the same executed in slave node give me this error:

The connection to the server 10.0.x.x:6443 was refused - did you specify the right host or port?

The solution that worked for me is as below:

I copied the $KUBECONFIG file of Master and places in the slave nodes .kube/ location and it worked (I have only 2 nodes, one master and one slave.)