Need help with a strange/customized test network

[christopher-pickens]

Hello everyone I have a rather unorthodox networking question. And bear with me I know this is crazy.....

So we are developing a customized application that needs to be able to talk between two laptops.

Each laptop has a virtual NIC that is tagging VLANs 7 with a /24 networking & 8 with a /26 network.

And below is the network topology:

Router (top)
Switch (middle)
- Port f1/0/45 connecting the switches and configured as an access port passing only vlan 7

Switch (bottom/access)
-client A (port f1/0/5 configured with a trunk port to the switch passing vlan 7 & 8)
-client B (port f1/0/6 configured with a trunk port to the switch passing vlan 7 & 8)

Other notes, we do not have control of the distribution switch or the router. And when I do the show mac address-table command client A is showing the same MAC address from vlan 7 & 8. And traffic between 7 & 8 cannot be allowed.

The current problem is that traffic between 7 & 7 is not working. And I apologize in advance I cannot post the configurations. I suspect that the software doing the tagging is causing an issue. When I look at the mac table on client A I see that it shows vlan 7 & 8 with two identical MAC's. But I need help from the experts here.

Thank you

[BradEast1]

I don't see any issue with both addresses resolving to a singular MAC address. Both frames are sourced from the same NIC. I have a switch connected to a router with multiple addresses, and see the same behavior:

          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
   1    0462.734e.0d48    DYNAMIC     Gi1/0/2
   2    0462.734e.0d48    DYNAMIC     Gi1/0/2

What do you mean by "And traffic between 7 & 8 cannot be allowed"?

[christopher-pickens]

Interesting. 

And what I mean by traffic needs to be separated is. VLAN 7 is going out to a router and can get to an intranet of sorts. But traffic on VLAN 8 needs to only talk to devices that are also on VLAN 8 hanging off the same switch. 

[BradEast1]

Then you should be able to use a L3 ACL at their default gateway or you can use a L2 VACL on the switch they're connected to.