Troubleshoot OIDC in Google Distributed Cloud

This page shows you how to identify and resolve OpenID Connect (OIDC) issues with Google Distributed Cloud.

Identifying OIDC issues

When OIDC is not working for Google Distributed Cloud, it's typically a result of a configuration problem in the OIDC specification in the cluster config file. This section provides instructions for reviewing logs and the OIDC specification to help identify the cause of an OIDC problem.

Reviewing the GKE Identity Service logs

GKE Identity Service supports OIDC in Google Distributed Cloud.

1. Use kubectl logs to print the GKE Identity Service logs:

   kubectl --kubeconfig CLUSTER_KUBECONFIG -n anthos-identity-service logs \
   deployment/ais --all-containers=true
   

2. Review the logs for errors that can help you diagnose OIDC problems.

   If you are unable to authenticate with OIDC, GKE Identity Service logs provide the most relevant and useful information for debugging the problem.

   For example, if the OIDC specification (in the cluster config file) has a typo in the issuerURL field, such as htps://accounts.google.com (missing a "t" in https), the GKE Identity Service logs will contain an entry like this:

   OIDC (htps://accounts.google.com) - Unable to fetch JWKs needed to validate OIDC ID token.
   

3. If you have identified a configuration issue in the logs, proceed to Reconfiguring OIDC.

4. If you are unable to diagnose and resolve the problem yourself, engage with Cloud Customer Care.

   Cloud Customer Care will need the GKE Identity Service logs and the OIDC specification to diagnose and resolve OIDC problems.

Checking the OIDC specification in your cluster

The OIDC information for your cluster is specified in the clientconfig object in the kube-public namespace.

1. Use kubectl get to print the OIDC resource for your cluster:

   kubectl --kubeconfig CLUSTER_KUBECONFIG -n kube-public get \
   clientconfig.authentication.gke.io default -o yaml
   

2. Review the field values to confirm the specification is configured correctly for your OIDC provider.

3. If you have identified a configuration issue in the specification, proceed to Reconfiguring OIDC.

4. If you are unable to diagnose and resolve the problem yourself, engage with Cloud Customer Care.

   Cloud Customer Care will need the GKE Identity Service logs and the OIDC specification to diagnose and resolve OIDC problems.

Reconfiguring OIDC

If you identified problems in either the GKE Identity Service logs or the the clientconfig object, you can reconfigure OIDC in your cluster (without re-creating the cluster) to address them. To reconfigure OIDC, edit the KRM default object of type clientconfig in thekube-public namespace:

kubectl --kubeconfig CLUSTER_KUBECONFIG -n kube-public edit clientconfig default

Details from the ClientConfig CRD are used to configure OIDC for both the Google Cloud console and the Authentication plugin for GKE Enterprise. For details about the OIDC Information included in the ClientConfig CRD, see the following YAML and associated table of field descriptions.

authentication:
  - name: oidc
    oidc:
      certificateAuthorityData: CERTIFICATE_STRING
      clientID: CLIENT_ID
      clientSecret: CLIENT_SECRET
      cloudConsoleRedirectURI: "http://console.cloud.google.com/kubernetes/oidc"
      deployCloudConsoleProxy: PROXY_BOOLEAN
      extraParams: EXTRA_PARAMS
      groupsClaim: GROUPS_CLAIM
      groupPrefix: GROUP_PREFIX
      issuerURI: ISSUER_URI
      kubectlRedirectURI: KUBECTL_REDIRECT_URI
      scopes: SCOPES
      userClaim: USER_CLAIM
      userPrefix: USER_PREFIX
    proxy: PROXY_URL

The following table describes the fields of the ClientConfig CRD oidc object.