I have got a large campus collpased backbone with two core 6509 systems connected to 30 stacks of 3750's.
Each stack of 3750's has 8 vlans. This leads to a large number of vlans on the core 6500s and as such a lot of spanning tree instances. Am I correct in saying that even with using Rapdid PVST+ then there will still be a seperate spanning tree instance per vlan? I think so because I can tweak the root bridge for each vlan. Is there any "optimisation" built into RAPID PVST+ to eliminate the overhead of all this? In other words, does RapidPVST+ automatically include MST to cut down the number of BPDU's and CPU etc?
Or do I need to manually build two MST instances for each wiring closet?
What would Cisco recommend here?