The URL Filtering profile specifies an action for each URL category. By default, all URL categories are set to allow when you Create a new URL Filtering profile. This means that the users will be able to browse to all sites freely and the traffic will not be logged. The firewall also comes predefined default URL filtering profile that allows access to all categories except the following threat-prone categories, which it blocks: abused-drugs, adult, gambling, hacking, malware, phishing, questionable, and weapons.
As a best practice, if you want to create a custom URL Filtering category, clone the default URL filtering profile and change the action in all allow categories to either alert or continue so that you have visibility into the traffic. It is also a best practice to set the proxy-avoidance-and-anonymizers category to block.
Action Description
alert The website is allowed and a log entry is generated in the URL filtering log.
allow The website is allowed and no log entry is generated.
block The website is blocked and the user will see a response page and will not be able to continue to the website. A log entry is generated in the URL filtering log.
continue The user will be prompted with a response page indicating that the site has been blocked due to company policy, but the user is prompted with the option to continue to the website. The continue action is typically used for categories that are considered benign and is used to improve the user experience by giving them the option to continue if they feel the site is incorrectly categorized. The response page message can be customized to contain details specific to your company. A log entry is generated in the URL filtering log. The Continue page doesn’t display properly on client systems configured to use a proxy server.
override The user will see a response page indicating that a password is required to allow access to websites in the given category. With this option, the security admin or helpdesk person would provide a password granting temporary access to all websites in the given category. A log entry is generated in the URL filtering log. See Configure URL Admin Override. The Override page doesn’t display properly on client systems configured to use a proxy server.
none The none action only applies to custom URL categories. Select none to ensure that if multiple URL profiles exist, the custom category will not have any impact on other profiles. For example, if you have two URL profiles and the custom URL category is set to block in one profile, if you do not want the block action to apply to the other profile, you must set the action to none. Also, in order to delete a custom URL category, it must be set to none in any profile where it is used.

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