Hi Parnassus.
My scenario is:
Building 1:
01 5406R core switch 1
05 2930M distibution switches
Building 2:
01 5406R core switch 2
08 2930M distibution switches
Both buildings are 2 kms far away
We want to virtualize both 5406R switches so that they can bee seen as one virtual chassis.
Each distribution switch is connected locally to its core switch via 10GE-SR but we want redundancy towards the second remote core 5406R switch. Because of distance, we would have to deploy 10GE-LR transceivers. And to avoid spanning tree, we need to aggregate 10GE-SR and LR ports.
Not a common scenario, but as you can see, It could be possible.
Regards