Take the 2-minute tour ×
Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free.

Linux newb starting out. Figuring it all out as I go along. Im trying to layer 2 bridge a virtual tap interface and an etehrnet interface. want to achieve this.

Tap0 =====> Br0 (Layer 2 only) ======> Eth2 (layer 2 only) =====> External device connected to eth2

config as the following:

sudo tunctl

sudo ifconfig tap0 netmask promisc up

sudo ifconfig eth2 promisc up

sudo brctl addbr br0

sudo brctl stp br0 off

sudo brctl addif br0 tap0

sudo brctl addif br0 eth2

sudo ifconfig br0 up

with tcp dump i cant see any traffic hitting tap0. The only way i can get a ping from to to work is by adding a route to with:

sudo route add br0.

OK thats fine it works, but im surprised i need to do it and that the tap interface isnt seeing traffic. I expected the bridge to forward the arp request to tap0 or reply on tap0's behalf.

Have i missed something? is adding the route the way to do it, or should it work at layer 2 with no routes?


share|improve this question

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.