How can I troubleshoot and resolve the issue of “instances failed to join the Kubernetes cluster'’?
I am a DevOps engineer and I am responsible for managing a Kubernetes cluster in a production environment. One of the new Instances I have provisioned is failing to join the cluster. Describe the troubleshooting steps that should I take to identify and resolve the issue.
In the context of AWS, you can troubleshoot and resolve this particular issue by using the several steps which are given below:-
Checking Instance status
You can use the cloud provider console or even the command line interface to verify the status of the instance. Try to ensure that the instance is running and has network connectivity.
# Check instance status using AWS CLI
Aws ec2 describe-instances –instance-ids
Checking Kubernetes cluster status
You can use the “kubect1” to check the status of the Kubernetes cluster and ensure that the control plane components are running appropriately.
# Check cluster nodes and components
Kubectl get nodes
Kubectl get pods -n kube-system
Examine Kubernetes logs
You should check the Kubernetes for any error related to the instance joining the cluster.
# Check logs of Kubernetes control plane components
Kubectl logs -n kube-system
Verify the node Configuration
You should try to ensure that the instance has the correct Kubernetes Configuration.
# Check kubelet configuration
Cat /etc/kubernetes/kubelet.conf
Checking networking setup
Try to verify that the instance can communicate with the other nodes In the cluster and with the Kubernetes API server.
# Check network connectivity to API server
Curl https://:6443/version --insecure