Prerequisites
Before you begin, make sure you have the following in place. In your CoreWeave organization, you must have:- A deployed CKS cluster with OIDC Workload Identity enabled.
- A user with the appropriate permissions to create and deploy AI Object Storage buckets and policies. These are enabled using an IAM Access Policy tied to the principal with the Object Storage Admin role, or an AI Object Storage organization access policy that grants the following permissions:
s3:CreateBucket,cwobject:CreateAccessKey,cwobject:EnsureAccessPolicy,cwobject:ListAccessPolicy,cwobject:DeleteAccessPolicy.
- A terminal. This tutorial is written for bash and zsh.
kubectlinstalled and accessible from your terminal path.- An S3 CLI client installed and accessible from your terminal path. This guide uses the AWS CLI but any S3 CLI should work.
Configure the CKS OIDC provider
Register your CKS cluster as a trusted OIDC identity provider for AI Object Storage. This lets Pods running in the cluster exchange their projected service account tokens for temporary S3 credentials.- Launch your CKS cluster.
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In the Cloud Console, retrieve the OIDC Issuer URL of your CKS cluster:
- Go to the Clusters page.
- Click the name of your desired cluster. A cluster details panel opens on the right.
- Copy the OIDC Issuer URL from the Overview section.
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Configure OIDC Workload Identity Federation in the Cloud Console using this OIDC Issuer URL.
Your organization must be flagged for this feature.
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Create a new OIDC configuration in the Workload Federation page.
- Click Create OIDC configuration. The configuration form opens.
- Set the configuration name (choose a name that indicates it is for federating CKS tokens with AI Object Storage).
- Enter the CKS cluster’s OIDC Issuer URL that you copied earlier into the Issuer URL field.
- Set the Client ID (Audience) field to
https://coreweave.com/iam(recommended) or choose another audience. - Click Create to save the configuration.
Configure kubectl and create a Kubernetes service account
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Download a kubeconfig for your CKS cluster:
- Go to the Tokens page.
- Click Create Token. The token creation form opens.
- Set the context for your cluster.
- Click Download to download the kubeconfig.
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Using the kubeconfig you downloaded, export an environment variable that
kubectluses to locate your kubeconfig. Fill in the path to the kubeconfig file you downloaded: -
Test that your
kubectlinstallation works:If the environment variable is set properly, you see the context you downloaded for your CKS environment from yourkubeconfig.yamlfile, and you see running Nodes for your CoreWeave environment. -
Create a Kubernetes service account. Create a
.yamlfile with the following data and save it to a file namedtest-service-account.yaml:test-service-account.yaml -
Create the account:
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Verify the account is created:
If successful,
test-service-accountis visible.
Grant the service account access to Object Storage
You must grant the service account’s federated identity access to AI Object Storage through an organization access policy. Use the OIDC Issuer URL you copied earlier and the service account name to construct the WIF principal:[OIDC-ISSUER-URL] with the OIDC Issuer URL from your cluster’s details panel.
The following example policy grants the service account full S3 access to all buckets in your organization:
Set up the workload
With the service account created and granted access, reference it from your AI Object Storage policies and from your workload Pod.- You can define AI Object Storage policies that reference a role of the form
[ISSUER]:[SUBJECT], where the issuer is discovered through the well-known URL and the subject follows a standard pattern for Kubernetes service accounts, based on namespace and service account name. - To get the OIDC well-known URL, go to the Cloud Console, navigate to the Clusters page, select your cluster, and copy the OIDC Issuer URL.
| Principal type | Syntax |
|---|---|
| Principal | [OIDC-ISSUER-URL]:system:serviceaccount:default:test-service-account |
Organization policy "principals" | ["role/[OIDC-ISSUER-URL]:system:serviceaccount:default:test-service-account"] |
Bucket policy "Principal" | {"AWS": "arn:aws:iam::[ORG-ID]:role/[OIDC-ISSUER-URL]:system:serviceaccount:default:test-service-account"} |
Create the workload Pod
Create a Pod manifest that mounts a projected service account token with the correct audience. The Pod uses this token to exchange for temporary AI Object Storage credentials at runtime. Replace[ORG-ID] with your CoreWeave organization ID, and replace [CONTAINER-IMAGE] with your application’s container image:
To work with AI Object Storage, configure your Pod’s S3 endpoints to use virtual addressing style and set the appropriate endpoint URL.
Configure S3 endpoints for Pods
Configure S3 endpoints for Pods
Because the environment variables handle credential exchange, you only need to configure the S3 endpoint and addressing style in your application. For example, with the AWS CLI:Alternatively, you can mount this configuration file into the container from a ConfigMap and set the When your workloads run inside a CKS cluster, use the LOTA endpoint (
AWS_CONFIG_FILE variable to the location of the mounted file.cwlota.com) for optimal performance. For more configuration options (Boto3, s3cmd, Multi-Storage Client), see Attaching endpoints.workload-pod.yaml
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Apply the manifest:
/var/run/secrets/tokens/oidc-token inside the Pod. AWS SDKs and the AWS CLI automatically use the AWS_CONTAINER_AUTHORIZATION_TOKEN_FILE and AWS_CONTAINER_CREDENTIALS_FULL_URI environment variables to exchange the OIDC token for temporary S3 credentials. Credentials rotate automatically based on the expirationSeconds value.
Optional: Verify the setup
To confirm the projected token exchange works before you deploy your real workload, create a test Pod that uses theamazon/aws-cli image:
test-manual-pod.yaml
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Apply the test Pod:
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Check the Pod logs for the response:
If your OIDC configuration and organization access policies are configured correctly, you see a JSON response that lists your buckets. If you see an
AccessDeniederror, verify that your organization access policies grant thes3:ListAllMyBucketsaction to the correct WIF principal. -
Clean up the test Pod:
Optional: Validate locally
You can also validate the OIDC token exchange from your local machine, outside of a Kubernetes Pod, by creating a service account token and calling the credential endpoint directly. This helps with one-time testing and debugging when you want to isolate the credential exchange from the rest of your workload. Additional local prerequisites:curlfor calling the credential endpoint.jqfor parsing JSON responses.- jwt.io (optional) for inspecting OIDC token contents.
Test that the service account token can authenticate
Create a service account token and exchange it for temporary AI Object Storage credentials. Replace[ORG-ID] with your CoreWeave organization ID:
Test access with the AWS CLI
Configure a local AWS CLI profile that uses a credential process script to fetch temporary credentials. Replace[CREDENTIAL-SCRIPT-PATH] with the path to your credential script (for example, /bin/cw-auth.sh). The script must obtain a service account token, exchange it at the credential endpoint, and return JSON in the format the AWS CLI expects. For a full walkthrough of writing this script, see Workload Identity Federation with a credential process.
The following commands set the virtual addressing style, the credential process, the region, and the endpoint URL in a new profile called cw-test:
Use the primary endpoint (
https://cwobject.com) for local testing because the LOTA endpoint (http://cwlota.com) is accessible only from within CoreWeave clusters.Next steps
- To use the automatic method instead, see Automatic authentication with the Pod Identity Webhook.
- Learn more about OIDC Workload Identity for CKS.
- Learn more about Workload Identity Federation for AI Object Storage.