Manually creating IAM for GCP

In environments where the cloud identity and access management (IAM) APIs are not reachable, or the administrator prefers not to store an administrator-level credential secret in the cluster kube-system namespace, you can put the Cloud Credential Operator (CCO) into manual mode before you install the cluster.

Alternatives to storing administrator-level secrets in the kube-system project

The Cloud Credential Operator (CCO) manages cloud provider credentials as Kubernetes custom resource definitions (CRDs). You can configure the CCO to suit the security requirements of your organization by setting different values for the credentialsMode parameter in the install-config.yaml file.

If you prefer not to store an administrator-level credential secret in the cluster kube-system project, you can choose one of the following options when installing OKD:

  • Use manual mode with GCP Workload Identity:

    You can use the CCO utility (ccoctl) to configure the cluster to use manual mode with GCP Workload Identity. When the CCO utility is used to configure the cluster for GCP Workload Identity, it signs service account tokens that provide short-term, limited-privilege security credentials to components.

  • Manage cloud credentials manually:

    You can set the credentialsMode parameter for the CCO to Manual to manage cloud credentials manually. Using manual mode allows each cluster component to have only the permissions it requires, without storing an administrator-level credential in the cluster. You can also use this mode if your environment does not have connectivity to the cloud provider public IAM endpoint. However, you must manually reconcile permissions with new release images for every upgrade. You must also manually supply credentials for every component that requests them.

  • Remove the administrator-level credential secret after installing OKD with mint mode:

    If you are using the CCO with the credentialsMode parameter set to Mint, you can remove or rotate the administrator-level credential after installing OKD. Mint mode is the default configuration for the CCO. This option requires the presence of the administrator-level credential during an installation. The administrator-level credential is used during the installation to mint other credentials with some permissions granted. The original credential secret is not stored in the cluster permanently.

Prior to a non z-stream upgrade, you must reinstate the credential secret with the administrator-level credential. If the credential is not present, the upgrade might be blocked.

Additional resources

For a detailed description of all available CCO credential modes and their supported platforms, see About the Cloud Credential Operator.

Manually create IAM

The Cloud Credential Operator (CCO) can be put into manual mode prior to installation in environments where the cloud identity and access management (IAM) APIs are not reachable, or the administrator prefers not to store an administrator-level credential secret in the cluster kube-system namespace.

Procedure

  1. Change to the directory that contains the installation program and create the install-config.yaml file:

    1. $ openshift-install create install-config --dir <installation_directory>

    where <installation_directory> is the directory in which the installation program creates files.

  2. Edit the install-config.yaml configuration file so that it contains the credentialsMode parameter set to Manual.

    Example install-config.yaml configuration file

    1. apiVersion: v1
    2. baseDomain: cluster1.example.com
    3. credentialsMode: Manual (1)
    4. compute:
    5. - architecture: amd64
    6.   hyperthreading: Enabled
    7. ...
    1This line is added to set the credentialsMode parameter to Manual.

  3. Generate the manifests by running the following command from the directory that contains the installation program:

    1. $ openshift-install create manifests --dir <installation_directory>

    where:

    <installation_directory>

    Specifies the directory in which the installation program creates files.

  4. Copy the generated credential files to the target manifests directory:

    1. $ cp ./<path_to_ccoctl_output_dir>/manifests/*credentials.yaml ./<path_to_installation>dir>/manifests/

    where:

    <path_to_ccoctl_output_dir>

    Specifies the directory created by the ccoctl alibabacloud create-ram-users command.

    <path_to_installation>dir>

    Specifies the directory in which the installation program creates files.

  5. From the directory that contains the installation program, obtain details of the OKD release image that your openshift-install binary is built to use:

    1. $ openshift-install version

    Example output

    1. release image quay.io/openshift-release-dev/ocp-release:4.y.z-x86_64

  6. Locate all CredentialsRequest objects in this release image that target the cloud you are deploying on:

    1. $ oc adm release extract quay.io/openshift-release-dev/ocp-release:4.y.z-x86_64 --credentials-requests --cloud=gcp

    This command creates a YAML file for each CredentialsRequest object.

    Sample CredentialsRequest object

    1. apiVersion: cloudcredential.openshift.io/v1
    2. kind: CredentialsRequest
    3. metadata:
    4.   labels:
    5.     controller-tools.k8s.io: "1.0"
    6.   name: openshift-image-registry-gcs
    7.   namespace: openshift-cloud-credential-operator
    8. spec:
    9.   secretRef:
    10.     name: installer-cloud-credentials
    11.     namespace: openshift-image-registry
    12.   providerSpec:
    13.     apiVersion: cloudcredential.openshift.io/v1
    14.     kind: GCPProviderSpec
    15.     predefinedRoles:
    16.     - roles/storage.admin
    17.     - roles/iam.serviceAccountUser
    18.     skipServiceCheck: true

  7. Create YAML files for secrets in the openshift-install manifests directory that you generated previously. The secrets must be stored using the namespace and secret name defined in the spec.secretRef for each CredentialsRequest object. The format for the secret data varies for each cloud provider.

  8. From the directory that contains the installation program, proceed with your cluster creation:

    1. $ openshift-install create cluster --dir <installation_directory>

    Before upgrading a cluster that uses manually maintained credentials, you must ensure that the CCO is in an upgradeable state.

Additional references

Admin credentials root secret format

Each cloud provider uses a credentials root secret in the kube-system namespace by convention, which is then used to satisfy all credentials requests and create their respective secrets. This is done either by minting new credentials with mint mode, or by copying the credentials root secret with passthrough mode.

The format for the secret varies by cloud, and is also used for each CredentialsRequest secret.

Google Cloud Platform (GCP) secret format

  1. apiVersion: v1
  2. kind: Secret
  3. metadata:
  4.   namespace: kube-system
  5.   name: gcp-credentials
  6. stringData:
  7.   service_account.json: <ServiceAccount>

Mint mode

Mint mode is the default Cloud Credential Operator (CCO) credentials mode for OKD on platforms that support it. In this mode, the CCO uses the provided administrator-level cloud credential to run the cluster. Mint mode is supported for AWS and GCP.

In mint mode, the admin credential is stored in the kube-system namespace and then used by the CCO to process the CredentialsRequest objects in the cluster and create users for each with specific permissions.

The benefits of mint mode include:

  • Each cluster component has only the permissions it requires

  • Automatic, on-going reconciliation for cloud credentials, including additional credentials or permissions that might be required for upgrades

One drawback is that mint mode requires admin credential storage in a cluster kube-system secret.

Mint mode with removal or rotation of the administrator-level credential

Currently, this mode is only supported on AWS and GCP.

In this mode, a user installs OKD with an administrator-level credential just like the normal mint mode. However, this process removes the administrator-level credential secret from the cluster post-installation.

The administrator can have the Cloud Credential Operator make its own request for a read-only credential that allows it to verify if all CredentialsRequest objects have their required permissions, thus the administrator-level credential is not required unless something needs to be changed. After the associated credential is removed, it can be deleted or deactivated on the underlying cloud, if desired.

Prior to a non z-stream upgrade, you must reinstate the credential secret with the administrator-level credential. If the credential is not present, the upgrade might be blocked.

The administrator-level credential is not stored in the cluster permanently.

Following these steps still requires the administrator-level credential in the cluster for brief periods of time. It also requires manually re-instating the secret with administrator-level credentials for each upgrade.

Next steps