MinIO External Identity Management Plugin


The MinIO Identity Management Plugin provides a REST interface for offloading authentication to an external identity manager through a webhook service.

Once enabled, client applications use the AssumeRoleWithCustomToken STS API extension to generate access tokens for MinIO. MinIO verifies this token by making a POST request to the configured plugin endpoint and uses the returned response to determine the authentication status of the client.

Configuration Settings

You can configure the MinIO Identity Management Plugin using the following environment variables or configuration settings:

Specify the following environment variables to each MinIO server in the deployment:


# All other envvars are optional
MINIO_IDENTITY_PLUGIN_COMMENT="External Identity Management using PROVIDER"

Set the following configuration settings using the mc admin config set command:

mc admin config set identity_plugin \
   url="" \
   role_policy="consoleAdmin" \

   # All other config settings are optional
   token="Bearer TOKEN" \
   role_id="external-auth-provider" \
   comment="External Identity Management using PROVIDER"

Authentication and Authorization Flow

The login flow for an application is as follows:

  1. Make a POST request using the AssumeRoleWithCustomToken API.

    The request includes a token used by the configured external identity manager for authenticating the client.

  2. MinIO makes a POST call to the configured identity plugin URL using the token specified to the STS API.

  3. On successful authentication, the identity manager returns a 200 OK response with an application/json content-type and body with the following structure:

       "user": "<string>",
       "maxValiditySeconds": 3600,
       "claims": "KEY=VALUE,[KEY=VALUE,...]"


    The owner of the requested credentials


    The maximum allowed expiry duration for the returned credentials


    A list of key-value pair claims associated with the requested credentials. MinIO reserves and ignores the exp, parent, and sub claims objects if present.

  4. MinIO returns a response to the STS API request that includes temporary credentials for use with making authenticated requests.

If the identity manager rejects the authentication request or otherwise encounters an error, the response must return a 403 FORBIDDEN HTTP status code with an application/json content-type and body with the following structure:

     "reason": "<string>"

The "reason" field should include the reason for the 403.

Creating Policies to Match Claims

Use either the MinIO Console or the mc admin policy command to create policies that match one or more claim values.