[Solved]  Couldn’t get current server API group list

Problem

Error Message:

$ kubectl get nodes 

E0526 10:52:08.347681   96830 memcache.go:265] 
couldn't get current server 
API group list: Get "http://localhost:8080/api?timeout=32s": 
dial tcp 127.0.0.1:8080: connect: connection refused

Cause

This error occurs when kubectl is unable to connect to the Kubernetes API server. This typically happens due to one of these reasons:

1. Running kubectl from a node that doesn’t have the proper kubeconfig file.
2. The API server being inaccessible.

Solution

To resolve this issue, follow these steps:

1. Check kubeconfig location: Ensure that the kubeconfig file is present in the correct location. By default, kubectl looks for the kubeconfig file in $HOME/.kube/config.

2. Verify kubeconfig contents: Check if the kubeconfig file contains the necessary configuration information to connect to the Kubernetes API server.

3. Run commands from controlplane node: If you have configured the kubeconfig file on the controlplane node, always run kubectl commands from this node.

4. Verify API server accessibility: Make sure the Kubernetes API server is running and accessible.

5. Set KUBECONFIG environment variable: If the kubeconfig file is located elsewhere, set the KUBECONFIG environment variable:

export KUBECONFIG=/path/to/kubeconfig

6. Use –kubeconfig flag: Alternatively, specify the kubeconfig file directly when running kubectl commands:

kubectl --kubeconfig=/path/to/kubeconfig get nodes

7. Verify network connectivity: Ensure that there are no firewall rules blocking access to the API server.

8. Restart kubectl: Sometimes, simply restarting kubectl can resolve connection issues.

Best Practices

• Always keep your kubeconfig file secure and up-to-date.
• Use role-based access control (RBAC) to manage permissions within your Kubernetes cluster.
• Regularly backup your kubeconfig file.
• Use namespaces to organize resources and improve security.

By following these steps and best practices, you should be able to resolve the “Couldn’t get current server API group list” error and successfully connect to your Kubernetes API server using kubectl.