Hi, I want to connect two pc`s on a redundant way with each other. On those pc`s a 64 bit ubuntu 11.10 is running with kernel version 3.0.0-16-generic. Setup1: ---------- PC1: PC2: br0 br1 | | -- eth0.1000 ---------------------------------------------------eth0.1000 | | __eth1.1001 ----------------------------------------------------eth1.1001 When I enable spanning tree on both bridges (brctl stp br0 on). They both stay sending BPDU packages and no port is disabled. So I get a loop. For some reason spanning tree is not working. Setup2: --------- When I repeat the following test without the VLANs the spanning tree protocol is working: br0 br1 | | -- eth0 -----------------------------------------------------eth0 | | __eth1 ------ -----------------------------------------------eth1 The problems is that in the final solution I only have vlans, so I need Setup1. Is spanning tree in Linux possible with VLANS? If so, how do I have to set-up this? Thanks, Koen