Hello All! Really hoping for some feedback here. It's come to my attention that in an equal cost path situation, SPBM will use the ODD B-VID (4051) to forward traffic via one path and the EVEN B-VID (4052) to forward traffic on another. I believe this is dependent on the i-sid's being EVEN vs ODD. At any rate, we've noticed that our switches will always prefer to forward traffic using the "Blue" path in the picture attached even if two equal cost paths exist when the destination is that to an ODD v-IST BMAC.
I tested this using l2 traceroutes, and although both switches in the v-IST cluster own the same virtual BMAC, it seems like the switch one of the switches owns it on 4051 and the other on 4052 but both respond. My question is, is multipathing within SPBM on by default? It doesn't seem this way because I have to manually lower the cost of the link on the RED path to force traffic to go over that path primarily (and it's only because its more cost effective to go there and then across the v-IST trunk). Is there a way to force traffic to egress from the switch on VLAN 4052?
Also, can someone outline the use case for STP-Multi-Homing within SPBM and if it applies here?
