Technical Tip: How to block Google Mail by Web Filter

[adubinina]

Description

This article describes how to block Google Mail by using a URL filter.

Solution

1. Configure the URL filter to block the following domains:
   
   
   • *gmail* - wildcard - block.
   • mail.google.* - wildcard – block.
   • accounts.google.com - Simple - block.
     
     
2. Apply the web filter and SSL Deep Inspection in the policy.
   
   
3. Import the CA certificate in the browser in order to avoid certificate errors.
   This configuration blocks Gmail when accessing it directly as well as via Google Search

Note:

This additional step is mandatory,  block QUIC protocol using application control or UDP 443, this way the connection will be over TCP/UDP.

The following references may also be of interest:

• Fortinet Cookbook: Preventing certificate warnings.
• Microsoft TechNet: Importing the certificates through the GPU.