Technical Tip : Direct Login Captive Portal for FortiProxy Authentication

The normal form-based authentication flow works like this:

1. The user attempts to access any external website.
2. FortiProxy intercepts the request and issues a redirect to the captive portal login page, with a unique auth-rule context in the query string.
3. The user submits credentials through the form.
4. Upon successful authentication, the user is redirected back to the original destination.

There are some cases because of browser cache behavior, the redirection will not work properly. The end user can opt to access the Captive Portal page directly and submit the credentials.

• FortiProxy address: 10.171.3.180
• The Captive Portal page will be: https://10.171.3.180:7831

This is based on the setting at Policy&Objects -> Proxy Auth Setting.

The portal page will look like this :

The end user can then select 'Login' and submit the credentials. The user information will be populated within FortiProxy, and the user can start accessing external websites.

FortiProxy v7.4.9 will have some improvements on the flow of how authentication rule matching will happen.