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For my current setup, I have a physical NIC on a XenServer machine that receives traffic tagged with various VLAN IDs. I have a virtual machine that is running Vyatta that needs to be able to access both tagged and untagged traffic in order to route traffic.

Here's the problem: 1) If I bind the NIC in XenCenter to the VM (which has no VLAN ID associated with it), the VM cannot see any tagged traffic. I have verified this using tcpdump. However, the tagged traffic is flowing into the XenServer machine perfectly fine. 2) I have more than 7 VLANs, so adding each VLAN as an interface within XenCenter isn't an option. 3) Even though tcpdump shows no tagged traffic coming in the VMs NIC, I have tried adding VLAN interfaces within Vyatta. This also doesn't work.

I have tried using both Linux bridge and openvswitch setups and neither seem to work. I am running XenServer 6.0.3 free and Vyatta VC6.3.

Please help! I've run out of ideas. I've googled for hours and can't seem to find anything.

share|improve this question
AFAIK, all VLAN traffic has been captured and de-encapsulated by Xen Dom0; all other VMs (DomU's) receive unencapsulated, untagged 802.3 frames from Dom0. If you need your Vyatta to access the tagged frames, you can't put it as a VM in XenServer. – pepoluan Feb 19 '13 at 22:13

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