Seemingly valid configuration is rejected

Use istioctl validate -f and istioctl analyze for more insight into why the configuration is rejected. Use an istioctl CLI with a similar version to the control plane version.

The most commonly reported problems with configuration are YAML indentation and array notation (-) mistakes.

Manually verify your configuration is correct, cross-referencing Istio API reference when necessary.

Invalid configuration is accepted

Verify that a validatingwebhookconfiguration named istio-validator- followed by <revision>-, if not the default revision, followed by the Istio system namespace (e.g., istio-validator-myrev-istio-system) exists and is correct. The apiVersion, apiGroup, and resource of the invalid configuration should be listed in the webhooks section of the validatingwebhookconfiguration.

{{< text bash yaml >}} $ kubectl get validatingwebhookconfiguration istio-validator-istio-system -o yaml apiVersion: admissionregistration.k8s.io/v1 kind: ValidatingWebhookConfiguration metadata: labels: app: istiod install.operator.istio.io/owning-resource-namespace: istio-system istio: istiod istio.io/rev: default operator.istio.io/component: Pilot operator.istio.io/managed: Reconcile operator.istio.io/version: unknown release: istio name: istio-validator-istio-system resourceVersion: "615569" uid: 112fed62-93e7-41c9-8cb1-b2665f392dd7 webhooks:

• admissionReviewVersions:
  • v1beta1
  • v1 clientConfig:

    caBundle should be non-empty. This is periodically (re)patched

    every second by the webhook service using the ca-cert

    from the mounted service account secret.

    caBundle: LS0t...

    service corresponds to the Kubernetes service that implements the webhook

    service: name: istiod namespace: istio-system path: /validate port: 443 failurePolicy: Fail matchPolicy: Equivalent name: rev.validation.istio.io namespaceSelector: {} objectSelector: matchExpressions:
    • key: istio.io/rev operator: In values:
      • default rules:
  • apiGroups:
    • security.istio.io
    • networking.istio.io
    • telemetry.istio.io
    • extensions.istio.io apiVersions:
    • '*' operations:
    • CREATE
    • UPDATE resources:
    • '' scope: '' sideEffects: None timeoutSeconds: 10 {{< /text >}}

If the istio-validator- webhook does not exist, verify the global.configValidation installation option is set to true.

The validation configuration is fail-close. If configuration exists and is scoped properly, the webhook will be invoked. A missing caBundle, bad certificate, or network connectivity problem will produce an error message when the resource is created/updated. If you don’t see any error message and the webhook wasn’t invoked and the webhook configuration is valid, your cluster is misconfigured.

Creating configuration fails with x509 certificate errors

x509: certificate signed by unknown authority related errors are typically caused by an empty caBundle in the webhook configuration. Verify that it is not empty (see verify webhook configuration). Istio consciously reconciles webhook configuration used the istio-validation configmap and root certificate.

1. Verify the istiod pod(s) are running:

   {{< text bash >}} $ kubectl -n istio-system get pod -lapp=istiod NAME READY STATUS RESTARTS AGE istiod-5dbbbdb746-d676g 1/1 Running 0 2d {{< /text >}}

2. Check the pod logs for errors. Failing to patch the caBundle should print an error.

   {{< text bash >}} $ for pod in $(kubectl -n istio-system get pod -lapp=istiod -o jsonpath='{.items[*].metadata.name}'); do
   kubectl -n istio-system logs ${pod}
   done {{< /text >}}

3. If the patching failed, verify the RBAC configuration for Istiod:

   {{< text bash yaml >}} $ kubectl get clusterrole istiod-istio-system -o yaml apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRole name: istiod-istio-system rules:

   • apiGroups:
     • admissionregistration.k8s.io resources:
     • validatingwebhookconfigurations verbs:
     • '*' {{< /text >}}

   Istio needs validatingwebhookconfigurations write access to create and update the validatingwebhookconfiguration.

Creating configuration fails with no such hosts or no endpoints available errors

Validation is fail-close. If the istiod pod is not ready, configuration cannot be created and updated. In such cases you’ll see an error about no endpoints available.

Verify the istiod pod(s) are running and endpoints are ready.

{{< text bash >}} $ kubectl -n istio-system get pod -lapp=istiod NAME READY STATUS RESTARTS AGE istiod-5dbbbdb746-d676g 1/1 Running 0 2d {{< /text >}}

{{< text bash >}} $ kubectl -n istio-system get endpoints istiod NAME ENDPOINTS AGE istiod 10.48.6.108:15014,10.48.6.108:443 3d {{< /text >}}

If the pods or endpoints aren't ready, check the pod logs and status for any indication about why the webhook pod is failing to start and serve traffic.

{{< text bash >}} $ for pod in $(kubectl -n istio-system get pod -lapp=istiod -o jsonpath='{.items[*].metadata.name}'); do
kubectl -n istio-system logs ${pod}
done {{< /text >}}

{{< text bash >}} $ for pod in $(kubectl -n istio-system get pod -lapp=istiod -o name); do
kubectl -n istio-system describe ${pod}
done {{< /text >}}