Single Sign-On with Microsoft Active Directory FS

This guide explains how to enable single sign-on (SSO) for applications being proxied by F5 NGINX Plus. The solution uses OpenID Connect as the authentication mechanism, with Microsoft Active Directory Federation Services (AD FS) as the Identity Provider (IdP) and NGINX Plus as the Relying Party (RP), or OIDC client application that verifies user identity.

This guide applies to NGINX Plus Release 36 and later. In earlier versions, NGINX Plus relied on an njs-based solution, which required NGINX JavaScript files, key-value stores, and advanced OpenID Connect logic. In the latest NGINX Plus version, the new OpenID Connect module simplifies this process to just a few directives.

Prerequisites

• A Microsoft AD FS instance, either on-premises or in Azure, with administrator privileges.

• An NGINX Plus subscription and NGINX Plus Release 36 or later. For installation instructions, see Installing NGINX Plus.

• A domain name pointing to your NGINX Plus instance, for example, demo.example.com.

Configure the AD FS Server

Microsoft Active Directory Federation Services (AD FS) serves as the Identity Provider.

Create an AD FS Application

1. In AD FS, open the Server Manager.

2. In Server Manager, select Tools, and then select AD FS Management.

3. In AD FS Management, right-click on Application Groups and select Add Application Group.

4. On the Application Group Wizard Welcome screen:

   • Enter the Name of your application, for example, NGINX Demo App.

   • Under Standalone applications, select Server application.

5. On the Application Group Wizard Server application screen:

   • Copy the Client Identifier value generated by AD FS. The client identifier is your AD FS Application ID, you will need it later when configuring NGINX Plus.

   • In Redirect URI, enter the Redirect URI for your NGINX Plus instance, for example, https://demo.example.com/oidc_callback, and then click Add.

6. On the Application Group Wizard Configure Application Credentials screen:

   • Select Generate a shared secret.

   • Copy and save the generated Client Secret, you will need it later when configuring NGINX Plus. You will not be able to view the secret after the application group is created.

   • Select Next to complete the steps for adding the application group.

Configure Logout URLs

After creating the application group, you need to configure the logout URLs to support RP-initiated logout:

1. In AD FS Management, navigate to Application Groups and select your application group.

2. Right-click on the application group and select Properties.

3. In the Properties dialog, add the post logout redirect URI to the application configuration:

   • Add the post logout URL, for example: https://demo.example.com/post_logout/.

4. To enable OpenID Connect front-channel logout (single sign-out when the user signs out of another application):

   • Use PowerShell to configure a LogoutUri for the AD FS client (there is no GUI option for this). For example, run:

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     Set-AdfsClient -TargetClientId <client-id> -LogoutUri https://demo.example.com/front_logout/

     Replace <client-id> with the Client Identifier from Step 5 above (the AD FS Application ID) and substitute the domain name of your NGINX Plus instance for demo.example.com.

     This registers a front-channel logout URL (LogoutUri) for the client in AD FS. When a user signs out of this or any other application in AD FS, the AD FS server sends a GET request to this URL (typically via a hidden iframe) with the user’s session ID (sid) as a query parameter, instructing NGINX Plus to clear the user’s session. According to the OpenID Connect front-channel logout specification, the identity provider is supposed to send both an issuer (iss) and a session ID; AD FS provides only the sid parameter, but the NGINX Plus OIDC module supports both the fully compliant iss+sid and the sid-only variants and will clear the session in either case.

Get the OpenID Connect Discovery URL

Check the OpenID Connect endpoint URL. By default, AD FS publishes the .well-known/openid-configuration document at the following address:

https://adfs-server-address/adfs/.well-known/openid-configuration.

1. Run the following curl command in a terminal:

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   curl https://adfs-server-address/adfs/.well-known/openid-configuration | jq .

   Where:

   • the adfs-server-address is your AD FS server address

   • the /adfs/.well-known/openid-configuration is the default address for AD FS for document location

   • the jq command (optional) is used to format the JSON output for easier reading and requires the jq JSON processor to be installed.

   The configuration metadata is returned in the JSON format:

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   {
       ...
       "issuer": "https://adfs-server-address/adfs",
       "authorization_endpoint": "https://adfs-server-address/adfs/oauth2/authorize/",
       "token_endpoint": "https://adfs-server-address/adfs/oauth2/token/",
       "jwks_uri": "https://adfs-server-address/adfs/discovery/keys",
       "userinfo_endpoint": "https://adfs-server-address/adfs/userinfo",
       "end_session_endpoint": "https://adfs-server-address/adfs/oauth2/logout",
       "frontchannel_logout_supported": true,
       "frontchannel_logout_session_supported": true
       ...
   }

2. Copy the issuer value, you will need it later when configuring NGINX Plus. Typically, the OpenID Connect Issuer for AD FS is:

   https://adfs-server-address/adfs.

You will need the values of Client ID, Client Secret, and Issuer in the next steps.

Set up NGINX Plus

With AD FS configured, you can enable OIDC on NGINX Plus. NGINX Plus serves as the Rely Party (RP) application — a client service that verifies user identity.

1. Ensure that you are using the latest version of NGINX Plus by running the nginx -v command in a terminal:

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   nginx -v

   The output should match NGINX Plus Release 36 or later:

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   nginx version: nginx/1.29.3 (nginx-plus-r36)

2. Ensure that you have the values of the Client ID, Client Secret, and Issuer obtained during AD FS Configuration.

3. In your preferred text editor, open the NGINX configuration file (/etc/nginx/nginx.conf for Linux or /usr/local/etc/nginx/nginx.conf for FreeBSD).

4. In the http {} context, make sure your public DNS resolver is specified with the resolver directive. By default, NGINX Plus re‑resolves DNS records at the frequency specified by time‑to‑live (TTL) in the record, but you can override the TTL value with the valid parameter:

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   http {
       resolver 10.0.0.1 ipv4=on valid=300s;
   
       # ...
   }

5. In the http {} context, define the AD FS OIDC provider named adfs by specifying the oidc_provider {} context:

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   http {
       resolver 10.0.0.1 ipv4=on valid=300s;
   
       oidc_provider adfs {
   
           # ...
   
       }
       # ...
   }

6. In the oidc_provider {} context, specify:

   • Your actual AD FS Client ID from Step 5 of AD FS Configuration with the client_id directive

   • Your Client Secret from Step 6 of AD FS Configuration with the client_secret directive

   • The Issuer URL from Step 2 of AD FS Configuration with the issuer directive

     The issuer is typically your AD FS OIDC URL. By default, NGINX forms the provider metadata endpoint by appending .well-known/openid-configuration to the issuer. For AD FS, this often resolves to https://adfs-server-address/adfs/.well-known/openid-configuration. If your AD FS issuer differs from https://adfs-server-address/adfs (for example, a custom path), you can explicitly specify the metadata document with the config_url directive.

   • The logout_uri is URI that a user visits to start an RP‑initiated logout flow.

   • The frontchannel_logout_uri directive defines the URI that receives OpenID Connect front-channel logout requests from AD FS. This URI must be an HTTPS path and must match the LogoutUri configured for the client in AD FS. When AD FS triggers a front-channel logout (for example, when a user signs out of another application), it sends a GET request to this URI (typically via a hidden iframe) with the session ID (sid) as a query parameter. The OIDC module clears the corresponding user session on NGINX Plus.

   • The post_logout_uri is absolute HTTPS URL where AD FS should redirect the user after a successful logout. This value must also be configured in the AD FS application properties.

   • If the logout_token_hint directive set to on, NGINX Plus sends the user’s ID token as a hint to AD FS. This directive is optional, however, if it is omitted the AD FS may display an extra confirmation page asking the user to approve the logout request.

   • If the userinfo directive is set to on, NGINX Plus will fetch /userinfo from the AD FS and append the claims from userinfo to the $oidc_claims_ variables.

   • PKCE (Proof Key for Code Exchange) is automatically enabled when the provider’s OpenID Connect discovery document advertises the S256 code challenge method in the code_challenge_methods_supported field. You can override this behavior with the pkce directive: set pkce off; to disable PKCE even when S256 is advertised, or pkce on; to force PKCE even if the IdP’s metadata does not list S256.

   • Important

     All interaction with the IdP is secured exclusively over SSL/TLS, so NGINX must trust the certificate presented by the IdP. By default, this trust is validated against your system’s CA bundle (the default CA store for your Linux or FreeBSD distribution). If the IdP’s certificate is not included in the system CA bundle, you can explicitly specify a trusted certificate or chain with the ssl_trusted_certificate directive so that NGINX can validate and trust the IdP’s certificate.

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   http {
       resolver 10.0.0.1 ipv4=on valid=300s;
   
       oidc_provider adfs {
           issuer                  https://adfs.example.com/adfs;
           client_id               <client_id>;
           client_secret           <client_secret>;
           logout_uri              /logout;
           post_logout_uri         https://demo.example.com/post_logout/;
           frontchannel_logout_uri /front_logout;
           logout_token_hint       on;
           userinfo                on;
   
           # Optional: PKCE configuration. By default, PKCE is automatically
           # enabled when the IdP advertises the S256 code challenge method.
           # pkce                  on;
       }
   
       # ...
   }

7. Make sure you have configured a server that corresponds to demo.example.com, and there is a location that points to your application (see Step 10) at http://127.0.0.1:8080 that is going to be OIDC-protected:

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   http {
   
       # ...
   
       server {
           listen      443 ssl;
           server_name demo.example.com;
   
           ssl_certificate     /etc/ssl/certs/fullchain.pem;
           ssl_certificate_key /etc/ssl/private/key.pem;
   
           location / {
   
               # ...
   
               proxy_pass http://127.0.0.1:8080;
           }
       }
       # ...
   }

8. Protect this location with AD FS OIDC by specifying the auth_oidc directive that will point to the adfs configuration specified in the oidc_provider {} context in Step 5:

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   # ...
   location / {
   
        auth_oidc adfs;
   
        # ...
   
        proxy_pass http://127.0.0.1:8080;
   
   }
   # ...

9. Pass the OIDC claims as headers to the application (Step 10) with the proxy_set_header directive. These claims are extracted from the ID token returned by AD FS:

   • $oidc_claim_sub - a unique Subject identifier assigned for each user by AD FS

   • $oidc_claim_email the e-mail address of the user

   • $oidc_claim_name - the full name of the user

   • any other OIDC claim using the $oidc_claim_ variable

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   # ...
   location / {
   
        auth_oidc adfs;
   
        proxy_set_header sub   $oidc_claim_sub;
        proxy_set_header email $oidc_claim_email;
        proxy_set_header name  $oidc_claim_name;
   
        proxy_pass http://127.0.0.1:8080;
   }
   # ...

10. Provide endpoint for completing logout:

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    # ...
    location /post_logout/ {
         return 200 "You have been logged out.\n";
         default_type text/plain;
    }
    # ...

11. Create a simple test application referenced by the proxy_pass directive which returns the authenticated user’s full name and email upon successful authentication:

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    # ...
    server {
        listen 8080;
    
        location / {
            return 200 "Hello, $http_name!\nEmail: $http_email\nAD FS sub: $http_sub\n";
            default_type text/plain;
        }
    }

12. Save the NGINX configuration file and reload the configuration:

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    nginx -s reload

Complete Example

This configuration example summarizes the steps outlined above. It includes only essential settings such as specifying the DNS resolver, defining the OIDC provider, configuring SSL, and proxying requests to an internal server.

http {
    # Use a public DNS resolver for Issuer discovery, etc.
    resolver 10.0.0.1 ipv4=on valid=300s;

    oidc_provider adfs {

        # The 'issuer' is typically your AD FS OIDC URL
        # e.g. https://adfs.example.com/adfs
        issuer https://adfs.example.com/adfs;

        # Replace with your actual AD FS Client ID and Secret
        client_id     <client_id>;
        client_secret <client_secret>;

        # RP‑initiated logout
        logout_uri /logout;
        post_logout_uri https://demo.example.com/post_logout/;
        logout_token_hint on;

        # Front-channel logout
        frontchannel_logout_uri /front_logout;

        # Fetch userinfo claims
        userinfo on;

        # Optional: PKCE configuration (enabled automatically when supported by the IdP)
        # pkce on;
    }

    server {
        listen      443 ssl;
        server_name demo.example.com;

        ssl_certificate     /etc/ssl/certs/fullchain.pem;
        ssl_certificate_key /etc/ssl/private/key.pem;

        location / {
            # Protect this location with AD FS OIDC
            auth_oidc adfs;

            # Forward OIDC claims as headers if desired
            proxy_set_header sub   $oidc_claim_sub;
            proxy_set_header email $oidc_claim_email;
            proxy_set_header name  $oidc_claim_name;

            proxy_pass http://127.0.0.1:8080;
        }

        location /post_logout/ {
            return 200 "You have been logged out.\n";
            default_type text/plain;
        }
    }

    server {
        # Simple test upstream server
        listen 8080;

        location / {
            return 200 "Hello, $http_name!\nEmail: $http_email\nAD FS sub: $http_sub\n";
            default_type text/plain;
        }
    }
}

Testing

1. Open https://demo.example.com/ in a browser. You will be automatically redirected to the AD FS sign-in page.

2. Enter valid AD FS credentials of a user who has access the application. Upon successful sign-in, AD FS redirects you back to NGINX Plus, and you will see the proxied application content (for example, "Hello, Jane Doe!").

3. Navigate to https://demo.example.com/logout. NGINX Plus initiates an RP‑initiated logout; AD FS ends the session and redirects back to https://demo.example.com/post_logout/.

4. Refresh https://demo.example.com/ again. You should be redirected to AD FS for a fresh sign‑in, proving the session has been terminated.

Legacy njs-based AD FS Solution

If you are running NGINX Plus R33 and earlier or if you still need the njs-based solution, refer to the Legacy njs-based Microsoft AD FS Guide for details. The solution uses the nginx-openid-connect GitHub repository and NGINX JavaScript files.

See Also

• NGINX Plus Native OIDC Module Reference documentation

• Release Notes for NGINX Plus R36

Revision History

• Version 3 (November 2025) – Updated for NGINX Plus R36; added front-channel logout support (frontchannel_logout_uri), PKCE configuration (pkce directive), and the client_secret_post token endpoint authentication method.

• Version 2 (August 2025) – Updated for NGINX Plus R35; added RP‑initiated logout (logout_uri, post_logout_uri, logout_token_hint) and userinfo support.

• Version 1 (March 2025) – Initial version (NGINX Plus Release 34).