This solution applies to the Barracuda NG Firewall Vx for VMWare ESX/ESXi.
If you are unable to add more than 5 NICs in the Barracuda NG Firewall Vx interface, please go to the VMware clients' "Edit Virtual Machine Settings" page to check the "Virtual Machine Version".
If the version is 4, additional NICs will not be added because of virtual machine restrictions. After stopping the Virtual Machine, right click on the Inventory Virtual Machine, then update the firmware of virtual machine from "Upgrade Virtual Hardware".
After this upgrade has completed, you should now be able to add the desired NICs.
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