to answer my own question, i did figure it out. although several google hits suggested that it was necessary to run vconfig and set up special bridges in the dom0, the way i got it working was to leave the dom0 totally alone and simply run vconfig in the domU, then assign an ip to the vlan interface. the other gotcha is that you *must* change the domU vlan interface mtu to 1496. otherwise small packets like pings will work, large packets will hang the connection. jason ---------- Forwarded message ---------- From: Jason Tower <<a href="mailto:jtower@gmail.com">jtower@gmail.com</a>> Date: Aug 13, 2006 12:21 PM Subject: vlan in a domU To: <a href="mailto:fedora-xen@redhat.com">fedora-xen@redhat.com</a> <div>is it possible to do 802.1q vlan tagging in a domU? i have it working fine in the dom0: # vconfig add eth0 560 (creates eth0.560 interface) # ifconfig eth0.560 <a href="http://10.10.10.140/24" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">10.10.10.140/24</a> (a subnet on vlan 560) # ping <a href="http://10.10.10.100" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">10.10.10.100</a> (success) but have been unsuccessful assigning <a href="http://10.10.10.141" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">10.10.10.141</a> to a domU and getting it to communicate with vlan 560. i've tried a wide variety of combinations of bridges, vconfigs, and xen domU vif settings, so far nothing has worked. is it even possible to do what i'm trying to do? or am i simply missing the secret sauce? </div><div> jason </div>