Dump client k8s certificates from your kubeconf for use in remote k8s with Kubernetai CoreDNS Plugin

k8s-api-server-certs

# Dump certs (client.crt, client.key, & ca.crt) in a directory called c3certs

export KUBECONFIG_PATH=/home/ec2-user/.kube/config
sudo cat $KUBECONFIG_PATH | grep client-certificate-data | cut -f2 -d : | tr -d ' ' | base64 -d > c3certs/client.crt
sudo cat $KUBECONFIG_PATH | grep client-key-data | cut -f2 -d : | tr -d ' ' | base64 -d > c3certs/client.key
sudo cat $KUBECONFIG_PATH | grep certificate-authority-data | cut -f2 -d : | tr -d ' ' | base64 -d > c3certs/ca.crt

# Load the above certificates as ConfigMap in Kubernetes running with CoreNS Kubernetai plugin
kubectl -n kube-system create cm c3certs --from-file=/home/ec2-user/c3certs