To perform SonicWall Content Filtering on HTTPS and SSL-based traffic using DPI-SSL
Scroll to the Global Settings section.
Select Enable Content Filtering Service.
Click Accept.
Navigate to the POLICY | DPI-SSL > Client SSL page.
Click General.
Select the Enable SSL Inspection checkbox.
Select the Content Filter checkbox.
Click Accept.
Navigate to a blocked site using the HTTPS protocol to verify that it is properly blocked.
For content filtering over DPI-SSL, the first time HTTPS access is blocked results in a blank page being displayed. If the page is refreshed, the user sees the firewall block page.