Troubleshooting kubeadm

509 Certificate Errors

If you see Unable to connect to the server: x509: certificate has expired or is not yet valid, try resetting ntp. This generally indicates that the date/time is not set on local system correctly.

If you see Unable to connect to the server: x509: certificate signed by unknown authority (possibly because of "crypto/rsa: verification error" while trying to verify candidate authority certificate "kubernetes"), try running these commands as a regular user:

  mv  $HOME/.kube $HOME/.kube.bak
  mkdir -p $HOME/.kube
  sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
  sudo chown $(id -u):$(id -g) $HOME/.kube/config

gcloud Errors

If you see the error ERROR: (gcloud.container.clusters.get-credentials) Unable to create private file [/etc/kubernetes/admin.conf]: [Errno 1] Operation not permitted: '/etc/kubernetes/admin.conf', create a backup of admin.conf and delete the admin.conf before attempting to reconnect to the cluster.

gcloud Authentication Example

The commands used to authenticate to gcloud are the following:

gcloud auth login
gcloud config set project <your gcloud project>
gcloud auth configure-docker

If you see gcloud authentication errors, execute gcloud config list then re-authenticate using the commands from above. Finally, rerun gcloud config list - the results should show different values if authentication was indeed the issue.

OpenShift Container Platform

Troubleshooting OpenShift Container Platform: Basics