Security profile features available in flow mode

When you change to flow mode, proxy mode antivirus and web filter security profiles are converted to flow mode and the following reduced set of security profiles features are available:

• AntiVirus
• Web Filter
• Application Control
• Cloud Access Security Inspection
• Intrusion Protection
• FortiClient Profiles

l  SSL Inspection

l  Web Rating Overrides

In flow mode, antivirus and web filter profiles only include flow-mode features. Web filtering and virus scanning is still done with the same engines and to the same accuracy, but some inspection options are limited or not available in flow mode. Application control, intrusion protection, and FortiClient profiles are not affected when switching between flow and proxy mode.

Unfortunately CASI does not work when using Proxy-based profiles for AV or Web fil- tering. Make sure to only use Flow-based profiles in combination with CASI on a spe- cific policy.

Even though VoIP profiles are not available from the GUI in flow mode, the FortiGate can process VoIP traffic. In this case the appropriate session helper is used (for example, the SIP session helper).

Setting flow or proxy mode doesn’t change the settings available from the CLI. However, you can’t save security profiles that are set to proxy mode.

You can also add add proxy-only security profiles to firewall policies from the CLI. So, for example, you can add a VoIP profile to a security policy that accepts VoIP traffic. This practice isn’t recommended because the setting will not be visible from the GUI.

Security profile features available in proxy mode

When set to proxy mode, the following security profiles are available:

• AntiVirus
• Web Filter
• DNS Filter
• Application Control
• Intrusion Protection
• Anti-Spam
• Data Leak Prevention
• VoIP
• ICAP
• Web Application Firewall
• FortiClient Profiles
• Proxy Options
• SSL Inspection
• Web Rating Overrides l  Web Profile Overrides l  ICAP Servers

In proxy mode, from the GUI you can only configure antivirus and web filter security profiles in proxy mode. From the CLI you can configure flow-based antivirus profiles, web filter profiles and DLP profiles and they will appear on the GUI and include their inspection mode setting. Also, flow-based profiles created when in flow mode are still available when you switch to proxy mode.

Changing between proxy and flow mode

By default proxy mode is enabled and you change to flow mode by changing the Inspection Mode on the

System Information dashboard widget. When you select Flow–based you are reminded that all proxy mode

profiles are converted to flow mode, removing any proxy settings. As well proxy-mode only features (for example, Web Application Profile) are removed from the GUI.

In addition, when you select Flow–based the Explicit Web Proxy and Explicit FTP Proxy features are removed from the GUI and the CLI. This includes Explicit Proxy firewall policies.

If required you can change back to proxy mode just as easily. As well, if your FortiGate has multiple VDOMs you can set the inspection mode independently for each VDOM.

Changing the FortiGate’s inspection mode to flow or proxy

You can select flow or proxy mode from the System Information dashboard widget to control your FortiGate’s security profile inspection mode. Having control over flow and proxy mode is helpful if you want to be sure that only flow inspection mode is used (and that proxy inspection mode is not used). As well, switching to flow inspection mode also turns off the explicit web proxy and the explicit FTP proxy, making sure that no proxying can occur.

In most cases proxy mode (the default) is preferred because more security profile features are available and more configuration options for these individual features are available. Some implementations; however, may require all security profile scanning to only use flow mode. In this case, you can set your FortiGate to flow mode knowing

that proxy mode inspection will not be used.

If you select flow-based to use external servers for FortiWeb and FortiMail you must use the CLI to set a Web Application Firewall profile or Anti-Spam profile to external mode and add the Web Application Firewall profile or Anti-Spam profile to a firewall policy.