<HTML><BODY><p>Hello everyone.</p><p>I looked through all the topics where combining VLANs with STP was discussed - there are few of them - but I am still not sure if this is possible to implement.</p><p>I am trying to bridge three interfaces, two of which are supposed to act as trunk (hdlc0 and hdlc1) and one is supposed to act as access port (eth0). I also need to enable RSTP on each interface included in bridge, but with the configuration listed below RSTP packets are sent via hdlc0 and hdlc1 tagged (!) so other devices rejects them. </p><p><br>Here's my configuration:</p><p>ifconfig eth0 up</p><p><br>ifconfig hdlc0 up<br>ifconfig hdlc1 up</p><p>vconfig add hdlc0 42<br>vconfig add hdlc1 42<br>ifconfig hdlc0.42 up<br>ifconfig hdlc1.42 up</p><p><br>brctl addbr br1<br>brctl addif br1 eth0<br>brctl addif br1 hdlc0.42<br>brctl addif br1 hdlc1.42</p><p>ifconfig br1 up<br>brctl stp br1 on</p><p>What I already tried: I tried to create two bridges: first with vlan interfaces, second with physical interfaces included. I enabled RSTP on second bridge and also created ebtables rule so second bridge won't consume tagged packets. I supposed RSTP will converge in underlying physical interface so vlan interfaces will be blocked as well, but it's not like that: RSTP converges on physical interfaces, but vlan interface is still unblockes, so loop occur.</p></BODY></HTML>