Overview

Kerio Control's Web Filter rates web page content. It uses a dynamic worldwide database that includes URLs and webpage classification.

Whenever users attempt to access a web page, Kerio Control sends a request on the page rating. According to the classification of the page, users are either allowed or denied access.

Web Filter requires a special license. Unless Kerio Control includes this module, it behaves like a trial version only (automatically disabled after 30 days).

Solution

Enabling Web Filter

1. In the administration interface, go to Content Filter > Applications and Web Categories. 
2. Check Enable Kerio Control Web Filter.
3. Check Allow authenticated users to report miscategorized URLs if the user believes that the page is in a wrong category (which makes Kerio Control block access to the page), they can suggest a change to the developers. All suggestions are logged in the Security log. If a page is still blocked after a couple of days, it can be added to the URL Whitelist.
   
   
4. Click Apply.  

Testing URLs

In the administration interface, it is possible to test URL categorization. It is then possible to make recategorization suggestions on the results page if desired. 

1. In the administration interface, go to Content Filter > Applications and Web Categories. 
2. Under the Kerio Control Web Filter section, enter a URL and click the Test URL.
   
   
3. In the URL Categorization dialog, check if the category is correct.

Creating a URL Whitelist

If Kerio Control Web Filter blocks a URL that should not be blocked, you can add it to the special list of enabled URLs:

1. In the administration interface, go to Content Filter > Applications and Web Categories. 
2. Click Add. 
3. Enter the URL and description of the website, you can specify:
   
   • Server name (e.g. https://www.google.com). The server name represents any URL at a corresponding server.
     
   • Address of a particular webpage (e.g. www.gfi.com/products-and-solutions/all-products).
   • URL using wildcard matching (e.g. *.gf?.*). An asterisk stands for any number of characters (even zero), a question-mark represents just one symbol.
     
4. Save the settings.

Using Web Filter in URL Rules

Whenever Kerio Control processes a URL rule that requires classification of pages, Kerio Control Web Filter is activated, for example, configuring a rule denying all users to access pages containing job vacancies:

1. In the administration interface, go to Content Filter.
2. On the Content Rules tab, enable the predefined rule Kerio Control Web Filter categories and applications.
   
3. Double-click the Detect content column and choose Add > Applications and Web Categories.
4. Check the Job Search rating category.
   
   
5. Click OK twice.
6. On the Content Rules tab, click Apply.

Confirmation

The configured web filters take effect and deny or allow access to the specified pages.

Related Articles

Configuring the Content Filter

Enabling Application Awareness