Network scheme:
Problem:
N3K are adding double tag to frames with dst-mac 01:00:0c:cd:cd:d0. If I change MAC to i.e. 01:00:0c:cd:cd:d6 problem doesn't occur. Second tag is with the same VID that first one.
On HUAWEI on client port is BPDU tunnel for l2protocol, same is on last DCN. If I bypass both N3K, everything works fine, frames are going through network properly with one tag. Soft on both N3K is
7.0(3)I4(7), N3K model are both C3064PQ.
I've already checked twice with SPAN how does these frames look on each device in above chain, and I'm sure that both N3K add second tag to these frames on egress port towards each other. I've tried to set testing lab with one N3K (same software but 3048 model, only spare that I have for now), and couldn't repeat that behaviour. Softs on each device was the same as in network.
I've searched cisco documentation for any information about these, but there is nothing. Is that MAC some kind of reserved MAC on N3K? Is there a list of reserved MAC for N3K? What could cause that behaviour? Or could it be bug?
