Port mirroring on vSwitch

Hello,

I have this scenario:

vSwitch0 -> vmnic0 --> physicalAppliance

|

|--> PortGroup0

|            |

|            |--> VirtualMachine0

|            |

|            |--> VirtualMachine1

|

|--> PortGroup1

              |

              |--> VirtualMachine2

I'd like to have that physicalAppliance'll to able to sniff all traffic generated from all VirtualMachines.

So, I've enabled Promiscuous mode on vSwitch0 (and on all PortGroups indirectly) and in this case any VirtualMachine is enabled to sniff the traffic generated from other two VirtualMachines, but physicalAppliance is not enabled. So, how can I configure vSwitch0 in order to enable port mirroring on vmnic0 (and on physicalAppliance indirectly)?

Thanks,

Andrea