Isolate NIC Traffic

Hope someone can guide me on this...

openSuse 13.1, 2 NICs installed (2nd just added).

I currently have a Win7 VM running on VirtualBox 4.3.6, which I use to VPN into work, using the Cisco VPN client within the VM, so it creates its own tunnel through the primary NIC to work, and all other traffic is unaffected. Works like a champ.

Work sent me an Aruba RAP3 to extend the corp network to my house, eliminating the need for the VPN. I have connected the Aruba to the secondary NIC, and pointed the VM to that NIC.

The VM will use 802.1x authentication to the corp network through the Aruba. I do not want any of the traffic from the host to go through that NIC, for obvious reasons.

Questions are:

1. How should the secondary NIC be configured? I use ifup rather than network manager. I think I just need the NIC to act as a transparent bridge to the Aruba, in other words, just acting as the path, but not needing any IP services itself. How is that achieved?

2. If I cannot have it as a transparent path, how would it need to be configured?

3. Do I need to enable 802.1x on that NIC, even though its not really doing anything?

enp4s0 = Primary NIC, all Linux traffic should go here
enp3s2 = Secondary NIC, all VM traffic should go here

If I configure enp3s2 as static, but do not assign an address, the following two interfaces show up on ifconfig

enp0s26u1 - shows no address and has a different MAC than enp3s2
enp3s2:av - this shows a 169.254.x.x address, and has the same MAC as enp3s2

Hope this all makes sense.

Thanks in advance