[c-nsp] cisco ASA using many time the same MAC and HP switches

[Matt Buford]

> Old HPs (such as the 4000) have a single switch-wide fdb. I've been
> bitten by this more times than I wish to recount. Anything new should
> have an fdb per VLAN.

One notable modern exception is QinQ.  Pushing your tags through a QinQ 
tunnel means that while in the tunnel all vlans are sharing a single table. 
This one has bitten me and forced me to never buy service from metro 
Ethernet providers using QinQ.