I have multiple buildings and would like to route at the distribution layer from each building. I have two stacked 3750 switches at each building for redundancy. There is fiber between each building. Total of three buildings. We will call them building 1, 2 , and 3. Building 3 has the distribution switch that goes through building 2 via Fiber. Building 2 traffic is aggregated with building 3 traffic which eventually makes it to the core at building 1. This is the Fiber layout. The buildings are close together. I need to route from building 3 to building 2. The access layer switches are 3com with no Vlan support they will just connect to the distribution switches. Then I want to route the traffic from there. I am not sure about layer 3 design routing with multiple Vlan's that represent subnets. How do you get the routing to go from one end say building 3 to building 2 and then to building 3 and visa versa. Say I use 10.0.1.x through 10.0.10.x at a class C subnet mask. Could I create all static routes between the stacked switches? But if I have more than one subnet on a switch how do you route traffic between the two. The master 3750 switch in the stack acts as a single router as far as the mac address is concerned. So I think for every IP addres default gateway per subnet it will us the mac address with the different default gateway. For example; 10.0.1.1 and 10.0.;2.1 and on the other side would I setup the same vlans and different IP address combinations? For example 10.0.1.2 and 10.0.2.2. If I have two fiber connections between the stacked switches how does routing work?