We have several (actually a lot of) QinQ transports (by the same provider) between one central location and many remote sites and we're looking for a way to reduce the number of physical connections at the central location (currently one interface per QinQ transport) - basically we'd like to do "multiple" QinQ termination (from the customer's point of view) on a single interface.
Selective QinQ might be a way (provided some restrictions are met) and we do have a C4500X available for it, but I still need some things cleared up:
I'm supposed to configure a new connection with our provider, who will send us double-tagged traffic, say with outer tags PVid1 and PVid2 (one for each QinQ transport). I'll have to "switchport mode trunk", "switchport vlan mapping CVid11,CVid12,...,CVid1m dot1q-tunnel PVid1" and "switchport vlan mapping CVid21,CVid22,...,CVid2n dot1q-tunnel PVid2", and I guess one restriction is that CVids must not overlap between PVids (please correct me if I'm wrong so far).
Should I also configure "switchport trunk allowed vlan PVid1,PVid2" and / or define PVid1 and PVid2 in the Vlan database? If so, that would also mean that PVids should not overlap with CVids or other Vlans defined on the switch...
How (if at all) will protocols like STP or CDP work over such a configuration?
Thank you.
