Specifications

Barracuda Web Filter Release 3.3
26 Chapter 2: Installation and Configuration
Advanced installation topics
This section describes advanced installation topics that may apply to your Barracuda Web Filter
deployment.
Inline pass-through with pre-existing proxy deployment
Another deployment type that is much less common than either Inline mode or Forward Proxy mode
is using the Barracuda Web Filter as an inline device that uses a pre-existing proxy server on your
network. This type of deployment is not recommended because it breaks the following features of the
Barracuda Web Filter:
• Infection reports do not display the IP addresses of infected clients.
• Infected clients cannot be automatically redirected to the Barracuda Spyware Removal Tool.
To resolve these issues, we recommend that you remove your pre-existing proxy server and deploy
the Barracuda Web Filter as described in Inline pass-through (transparent) mode on page 11.
If you choose to deploy your Barracuda Web Filter with a pre-existing proxy server, place the
Barracuda Web Filter directly between your Internet firewall/router and your LAN router/switch that
connects to all your client machines. The Barracuda Web Filter is also configured to interact with and
scan the traffic from your pre-existing proxy server. The placement of your pre-existing proxy server
and its functionality may have an impact on the Barracuda Web Filter deployment. Some
configurations may require technical assistance from Barracuda Technical Support.
In this deployment, the Barracuda Web Filter detects all network traffic. The proxy server connects
directly to the Barracuda Web Filter LAN port. This connection may require a crossover cable. No
special port or IP address is required. The Barracuda Web Filter scans for all inbound and outbound
HTTP traffic from the proxy server. All outbound traffic on other ports is scanned for normal spyware
communication.
Figure 2.5 illustrates this deployment type.