Hi, I have Linux bridge between two switches that run STP. switch1-----Linux bridge-----switch2. Linux bridge planned to inspect all traffic, being absolutely transparent and take no part in STP. According to my tests with latest 2.6.27.9 and from what I understand from few threads in this list (correct me if I wrong), Linux bridge does not forward BPDU, bridge should use them. I refer to Stephen patch: http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.27.y.git;a=commitdiff;h=43aa1920117801fe9ae3d1fad886b62511e09bee In case I need completely transparent bridge, what are my options would be? Thanks ,Igor.