You can enable virus scanning on a per URL basis. It should only be enabled for URLs which allow file uploads and downloads because virus checking is a performance intensive task.
To enable Antivirus for file uploads/downloads
- From the SECURITY > Advanced Security page in the Advanced Security section, identify the service for which you want to enable Antivirus checking.
- Click Edit next to that Service. The Edit URL Policy window appears.
- In the Edit URL Policy section:
- Set Enable Virus Scan to Yes.
- Set Status to On.
- Set Mode to Active.
- Click Save.
When Virus Scan is enabled for a Service, all requests passing through the Barracuda Load Balancer ADC for that Service are scanned for viruses, and any traffic containing viruses is blocked.
The Barracuda Load Balancer ADC uses the Clam AV integrated Antivirus engine to scan files for embedded viruses and malware. AV signatures are created based on research conducted by Barracuda engineers. These AV signatures are sent to all deployed Barracuda Load Balancer ADCs with active Energize Updates subscriptions. The Barracuda Load Balancer ADC Antivirus engine supports the same file types the Clam AV engine supports. The Antivirus engine also uses streaming, so blocks of data are sent to the AV engine as they are received. Once the AV engine returns scanned data, the data is pushed to the back-end server.
The default size for the Antivirus scanning file is 25Mb. Although Barracuda Networks Technical Support can change this file size, customers cannot change this setting. When the Barracuda Load Balancer ADC receives an Antivirus scanning file larger than 25MB, the Clam engine rejects connection request and a log entry, indicating that the Antivirus scanning file is too large, is also generated.