quarkusio/quarkus · error · IllegalStateException

Openshift was requested as a deployment, but the target clus

Error message

Openshift was requested as a deployment, but the target cluster is not an Openshift cluster!

What it means

When OpenShift is listed as a deployment target, the deployer connects to the configured cluster and probes for the openshift.io API group to verify it is actually an OpenShift cluster. If the API group is absent, the target cluster is plain Kubernetes, and OpenShift-specific DeploymentConfigs cannot be applied, so the build fails with this IllegalStateException.

Source

Thrown at extensions/kubernetes/vanilla/deployment/src/main/java/io/quarkus/kubernetes/deployment/OpenshiftDeployer.java:32

import io.quarkus.kubernetes.spi.KubernetesDeploymentClusterBuildItem;

public class OpenshiftDeployer {

    @BuildStep
    public void checkEnvironment(Optional<SelectedKubernetesDeploymentTargetBuildItem> selectedDeploymentTarget,
            List<GeneratedKubernetesResourceBuildItem> resources,
            KubernetesClientBuildItem kubernetesClientBuilder,
            BuildProducer<KubernetesDeploymentClusterBuildItem> deploymentCluster) {
        selectedDeploymentTarget.ifPresent(target -> {
            if (!KubernetesDeploy.INSTANCE.checkSilently(kubernetesClientBuilder)) {
                return;
            }
            if (target.getEntry().getName().equals(OPENSHIFT)) {
                try (var openShiftClient = kubernetesClientBuilder.buildClient().adapt(OpenShiftClient.class)) {
                    if (openShiftClient.hasApiGroup("openshift.io", false)) {
                        deploymentCluster.produce(new KubernetesDeploymentClusterBuildItem(OPENSHIFT));
                    } else {
                        throw new IllegalStateException(
                                "Openshift was requested as a deployment, but the target cluster is not an Openshift cluster!");
                    }
                } catch (Exception e) {
                    throw new RuntimeException(
                            "Failed to configure OpenShift. Make sure you have the Quarkus OpenShift extension.", e);
                }
            }
        });
    }
}

View on GitHub (pinned to e1c734241f)

Solutions

  1. Point kubectl/client config at a real OpenShift cluster (oc login / correct KUBECONFIG context).
  2. Switch the deployment target to kubernetes: quarkus.kubernetes.deployment-target=kubernetes if the cluster is vanilla Kubernetes.
  3. Verify the cluster with 'kubectl get --raw /.well-known/openid-configuration' or check API groups; ensure the right context with 'kubectl config current-context'.

Example fix

// before (target is plain Kubernetes)
quarkus.kubernetes.deployment-target=openshift
// after
quarkus.kubernetes.deployment-target=kubernetes
Defensive patterns

Strategy: validation

Validate before calling

// Probe the cluster's API groups before choosing the openshift deployment target
boolean isOpenShift = client.getApiGroups().getGroups().stream()
    .anyMatch(g -> g.getName().equals("openshift.io"));
if (!isOpenShift) {
    System.setProperty("quarkus.kubernetes.deployment-target", "kubernetes");
}

Try / catch

try {
    deploy();
} catch (IllegalStateException e) {
    if (e.getMessage().contains("target cluster is not an Openshift cluster")) {
        // fall back to vanilla kubernetes target
        System.setProperty("quarkus.kubernetes.deployment-target", "kubernetes");
        deploy();
    } else { throw e; }
}

Prevention

When it happens

Trigger: quarkus.openshift.deploy=true (or openshift in quarkus.kubernetes.deployment-target) against a cluster that does not expose the openshift.io API group.

Common situations: Pointing quarkus.openshift.* config at a vanilla Kubernetes cluster (minikube, kind, EKS/GKE/AKS); KUBECONFIG/context pointing to the wrong cluster in CI.

Related errors

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/936067e07d8d925f. Report an issue: GitHub.