TAP Interface has a limitation ?
For 2 days, i’ve been working on a topology about inter-vlan routing, all in an emulated environment, Dyna(mips/gen) + two tap interfaces as my nodes.
tap0 in VLAN 2, tap1 in VLAN 3 , VLANs on the same switch ( 3660 + NM-16ESW as my switch), dot1q link between switch and router… bla bla bla
Well, it didn’t work, can’t ping each tap from another, so what’s going on ? I checked my configuration twice… then three times, then four…. then search for some tutorials about inter-vlan routing… ( oh my god :s ) but always the same problem…
So i’ve just check those two tap interfaces on the same switch trying to ping each from other!
debug ip packet , debug ip icmp… always nothing…
Why not try arping? let’s go, debup arp…. always no response…!
Well I finally capture the traffic… and what did i see ?
From both sides of the switch… no trace of any ARP response… the tap interface didn’t want to tell what was its MAC address to fill the CAM table 
If any has an answer about this… I’m ready to hear it!
1 Comment to TAP Interface has a limitation ?
I had exactly the same problem.
Remember in august !
But i didn’t find a solution btw
October 19, 2007