[c-nsp] Same MAC addresses from two ports on different VLAN

[Peter Rathlev]

On Fri, 2010-03-12 at 14:21 -0500, Jay Nakamura wrote:
> The reason I am posting this here is simple, does Cisco switches do
> the same thing?  Or if MAC address comes from two ports on different
> VLAN, would it just forward per VLAN?  Or would it depend on the
> model?

There are many situations where no per-VLAN-forwarding database could
lead to problems. AFAIK all SVIs on Catalyst switches (e.g. 6500) use
the same MAC address. Likewise all subinterfaces on a 7200 share the MAC
address of the primary interface.

I know for certain that models 3550 (now EoL), 3560, 3750 and 6500
behave as you expect with per-VLAN FDB.

Extreme switches must be made for some very special networks. :-)

-- 
Peter