Keycloak: An Open-Source IAM Solution

5. Enterprise IAM Integration (Advanced)

Keycloak is an open-source Identity and Access Management (IAM) solution with a robust implementation of the OIDC (OpenID Connect) and OAuth 2.0 standards.

What Is Keycloak?

Keycloak provides a complete “server software dedicated to authentication and authorization”, so you don’t need to develop login logic yourself. It is developed primarily by Red Hat, and it is a trusted tool in enterprise environments.

Comparison of Key Roles

Role	Description	Example
Identity Provider	Manages user account information and verifies identity	ID/password verification, sign-up, session management
User Federation	Integrates with account information from existing internal systems	LDAP, Active Directory (AD) connection
Identity Brokering	Connects to external social login services	Google, GitHub login integration
Single Sign-On (SSO)	Access all connected apps with a single login	Signing in to company email also signs you in to the groupware

Keycloak Architecture and SSO Flow

Keycloak acts as a central authentication hub for multiple services.

    graph TD
    User[User]
    KC[Keycloak IAM]
    App1[Web Application A]
    App2[Mobile App B]
    App3[Kubernetes API]
    LDAP[(Internal LDAP/AD)]

    User -- "1. Login request" --> KC
    KC -- "2. Verify account" --> LDAP
    KC -- "3. Issue ID Token" --> User
    
    User -- "4. Present token" --> App1
    User -- "4. Present token" --> App2
    User -- "4. Present token" --> App3
    
    App1 & App2 & App3 -- "5. Validate token" --> KC

Summary of Key Features

Standard protocol support: Fully supports OpenID Connect, OAuth 2.0, and SAML 2.0.
Centralized management: Control users, permissions, and clients in one place through the admin console.
Strong security settings: Easily configure MFA (multi-factor authentication), password policies, session timeouts, and more.
Customizable UI: Customize the login screen and themes to match corporate branding.

Using Keycloak with Kubernetes

The Kubernetes API server natively supports OIDC authentication. Using Keycloak as the cluster’s OIDC identity provider (IdP) provides the following benefits.

Integration with existing accounts: Use kubectl with existing company accounts, without issuing separate client certificates
Automated permission management: Map Keycloak groups to Kubernetes RBAC subjects to control permissions
Stronger security: Secure cluster access with short-lived tokens and MFA

Keycloak is an excellent choice for organizations that want to standardize and modernize a complex authentication setup.

OpenID Connect (OIDC) Concepts Configuring Keycloak OIDC on the API Server