Technical Tip: Trigger a captive portal only when specific websites are accessed while blocking access to all other websites

[raksshaya]

Description	This article describes how to configure FortiGate to trigger a captive portal only when specific websites are accessed, ensuring that the portal does not appear during general internet usage.
Scope	FortiGate.
Solution	Create web rating override: Go to Security Profiles -> Web Rating Overrides -> Create new. Enter the URL and override to Custom Categories, sub-Category custom1. Enter all the specific URLs that should prompt the captive portal and change the category to Custom. Web Profile. Go to Security Profiles -> Web Filter -> Create new. Select anywhere on the category and ctrl + A to select all categories and set action Block to block all the websites. Set custom1 action to Authenticate. Specify the user group who can access that website.                                                                           Policy: Go to Policy & Objects -> Firewall policy. Add the newly created web filter profile to the relevant policy and configure SSL inspection as Deep Inspection. Download the Deep inspection certificate to the local machine.   Save the policy. The authentication will work in Webfilter. Proxy based and the firewall policy is proxy based. Download the certificate: Go to Policy -> SSL inspection -> Edit. Download the certificate. Open the downloaded file .cer. Select Install the certificate. Select Local machine. Select 'Place all certificates in the following store' and Browse the 'Trusted Root Certificate Authorities' folder. Select finish. Note if the import is successful.