kubernetes/kops · error

cannot build kubernetes api client for %q: %v

Error message

cannot build kubernetes api client for %q: %v

What it means

Wraps a failure of kubernetes.NewForConfig in checkControlPlaneRunningVersion: the client config loaded fine, but a Kubernetes clientset could not be constructed from it (e.g. invalid server URL or auth setup for the cluster context).

Source

Thrown at cmd/kops/update_cluster.go:645

			}
		}
		return false
	}
}

// checkControlPlaneRunningVersion returns the minimum control plane running version
func checkControlPlaneRunningVersion(ctx context.Context, clusterName string, version string) (string, error) {
	configLoadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
	config, err := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
		configLoadingRules,
		&clientcmd.ConfigOverrides{CurrentContext: clusterName}).ClientConfig()
	if err != nil {
		return version, fmt.Errorf("cannot load kubecfg settings for %q: %v", clusterName, err)
	}

	k8sClient, err := kubernetes.NewForConfig(config)
	if err != nil {
		return version, fmt.Errorf("cannot build kubernetes api client for %q: %v", clusterName, err)
	}

	parsedVersion, err := apisutil.ParseKubernetesVersion(version)
	if err != nil {
		return version, fmt.Errorf("cannot parse kubernetes version %q: %v", clusterName, err)
	}
	nodeList, err := k8sClient.CoreV1().Nodes().List(ctx, metav1.ListOptions{
		LabelSelector: "node-role.kubernetes.io/control-plane",
	})
	if err != nil {
		return version, fmt.Errorf("cannot list nodes in cluster %q: %v", clusterName, err)
	}
	for _, node := range nodeList.Items {
		if apisutil.IsKubernetesGTE(node.Status.NodeInfo.KubeletVersion, *parsedVersion) {
			version = node.Status.NodeInfo.KubeletVersion
			parsedVersion, _ = apisutil.ParseKubernetesVersion(version)
		}

View on GitHub (pinned to 4c8573c808)

Solutions

1. Check the cluster entry's server URL in kubeconfig
2. Refresh credentials with kops export kubecfg
3. Verify client certificate/auth plugin availability

When it happens

Trigger: Thrown at cmd/kops/update_cluster.go:645 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/3c7a5e54da371b4f. Report an issue: GitHub.