Problem 

The key challenge emerged when the university aimed to implement Kerberos Single Sign-On (SSO) for FreeIPA and configure Keycloak to seamlessly connect with FreeIPA. Two significant updates revealed obstacles: an inability to access a third-party application for Kerberos installation and the absence of a topology or visual representation of the configuration. 

Additionally, the university encountered an error during LDAP user federation with Kerberos, manifesting in failed SPNEGO authentication. The accompanying debug output from the KRB5_TRACE highlighted issues related to handling Kerberos credentials and log entries signaling failed authentication attempts.

Remedy 

To address these challenges, the university explored FreeIPA’s documentation on external Identity Provider (IDP) support. The link to the documentation 

(https://freeipa.readthedocs.io/en/latest/workshop/12-external-idp-support.html) was provided to the client for verification of the steps outlined. 

Despite initial hurdles, a viable solution emerged. The university successfully achieved user authentication from Keycloak by leveraging the SSSD option under “user federation” instead of relying on Kerberos or LDAP. 

Conclusion 

The successful resolution of the authentication challenges showcases the adaptability of the chosen solution. The University’s decision to pivot towards SSSD under “user federation” not only resolved the immediate issues but also exemplified a flexible and effective approach to achieving the desired outcome.