Configure Generic OIDC

If your organization uses an OIDC provider for user authentication, you can configure Rancher to allow login using Identity Provider (IdP) credentials. Rancher supports integration with the OpenID Connect (OIDC) protocol and the SAML protocol. Both implementations are functionally equivalent when used with Rancher. The following instructions describe how to configure Rancher to work using the OIDC protocol.

Prerequisites

• In Rancher:
  • Generic OIDC is disabled.

note

Consult the documentation for your specific IdP to complete the listed prerequisites.

• In your IdP:

  • Create a new client with the settings below:

    Setting	Value
    Client ID	<CLIENT_ID> (e.g. rancher)
    Name	<CLIENT_NAME> (e.g. rancher)
    Client Protocol	openid-connect
    Access Type	confidential
    Valid Redirect URI	https://yourRancherHostURL/verify-auth

  • In the new OIDC client, create mappers to expose the users fields.

    • Create a new Groups Mapper with the settings below:

      Setting	Value
      Name	Groups Mapper
      Mapper Type	Group Membership
      Token Claim Name	groups
      Add to ID token	OFF
      Add to access token	OFF
      Add to user info	ON

    • Create a new Client Audience with the settings below:

      Setting	Value
      Name	Client Audience
      Mapper Type	Audience
      Included Client Audience	<CLIENT_NAME>
      Add to access token	ON

    • Create a new "Groups Path" with the settings below.

      Setting	Value
      Name	Group Path
      Mapper Type	Group Membership
      Token Claim Name	full_group_path
      Full group path	ON
      Add to user info	ON

• Important: Rancher will use the value received in the "sub" claim to form the PrincipalID which is the unique identifier in Rancher. It is important to make this a value that will be unique and immutable.

Configuring Generic OIDC in Rancher

1. In the upper left corner of the Rancher UI, click ☰ > Users & Authentication.

2. In the left navigation bar, click Auth Provider.

3. Select Generic OIDC.

4. Complete the Configure an OIDC account form. For help with filling the form, see the configuration reference.

5. Click Enable.

   Rancher will redirect you to the IdP login page. Enter your IdP credentials to validate your Rancher Keycloak configuration.

   note

   You may need to disable your popup blocker to see the IdP login page.

Result: Rancher is configured to work with your provider using the OIDC protocol. Your users can now sign into Rancher using their IdP logins.

Configuration Reference

Field	Description
Client ID	The Client ID of your OIDC client.
Client Secret	The generated Secret of your OIDC client.
Private Key/Certificate	A key/certificate pair to create a secure shell between Rancher and your IdP. Required if HTTPS/SSL is enabled on your OIDC server.
Endpoints	Choose whether to use the generated values for the Rancher URL, Issue, and Auth Endpoint fields or to provide manual overrides if incorrect.
Rancher URL	The URL for your Rancher Server.
Issuer	The URL of your IdP. If your provider has discovery enabled, Rancher uses the Issuer URL to fetch all of the required URLs.
Auth Endpoint	The URL where users are redirected to authenticate.

Troubleshooting

If you are experiencing issues while testing the connection to the OIDC server, first double-check the configuration options of your OIDC client. You can also inspect the Rancher logs to help pinpoint what's causing issues. Debug logs may contain more detailed information about the error. Please refer to How can I enable debug logging in this documentation.

All Generic OIDC related log entries are prepended with either [generic oidc] or [oidc].

You are not redirected to your authentication provider

If you fill out the Configure a Generic OIDC account form and click on Enable, and you are not redirected to your IdP, verify your OIDC client configuration.

The generated Issuer and Auth Endpoint are incorrect

If the Issuer and Auth Endpoint are generated incorrectly, open the Configure an OIDC account form, change Endpoints to Specify (advanced) and override the Issuer value.

Error: "Invalid grant_type"

In some cases, the "Invalid grant_type" error message may be misleading and is actually caused by setting the Valid Redirect URI incorrectly.