I have 2 Vlans, 10 and 20 on my 3560. Now I map instance 1 to vlan 10 and instance 2 to vlan 20.Ge0/1 is a vlan 10 access port and Ge0/2 is a vlan 20 access port. The rest of the configurations are left at defaults. Now I connect another s/w say a 3550 with a simillar configuration in such a way Ge0/1 of 3550 ( access of vlan 10) is connected to Ge0/1 of 3560 and Ge0/2 (access port of vlan 20) is connected to Ge0/2 of 3560. Wht will be state of the ports considering that my 3560 will be the root bridge for both instances.
What i feel is Ge0/1 will be kept forwarding for Vlan 10 and Ge0/2 will bw kept forwarding for Vlan 20. Either of the ports will be blocked for the other Vlan.
Do correct me if i am wrong to state the same.