Port mirroring not working as expected

[brucexx]

I have a Cisco switch with SPAN enabled. It is a very basic configuration with port 1 being the source port and port 2 being the destination port in both directions.

Port 1 in access mode belonging to VLAN 10 with native VLAN 1. Port 2 is an access mode belonging to VLAN 1 with native VLAN 1.

When I connect my laptop to port 2 and run Wireshark I get what I would expect to get - tons of traffic...

When I connect a VM running on Proxmox 3.4 with a dedicated interface and is plugged into port 2 on the switch all I am getting is ARP and STP (RSTP) traffic.

Is there anything else I need to do on Proxmox ? I check on two VMs Windows server 2008 and Ubuntu - with the same result.

Any suggestions ? Is the native VLAN messing me up ? ...but what it would have to do with Proxmox only ?

 

[wolfgang]

Hi,

how do you pass the nic to the VM?
And what is your VM config look like?

 

[brucexx]

how do you pass the nic to the VM?
The NIC is on vmbr1 that includes eth3 interface directly connected to the port 2 (destination port)

I also made sure that while testing I am selecting the proper interface in Wireshark.


And what is your VM config look like?
Windows VM
bootdisk: virtio0
cores: 4
memory: 8196
name: Win2012R2
net0: e1000=0A:8C:AF:BE:02:89,bridge=vmbr0
net1: e1000=76:AF:85:79:FE:04,bridge=vmbr1
numa: 0
ostype: win8
smbios1: uuid=4e21d816-c3d1-4cb0-b367-de792ed25fb2
sockets: 1
virtio0: local:240/vm-240-disk-1.qcow2,format=qcow2,cache=writeback,size=300G

Linux VM
bootdisk: virtio0
cores: 2
memory: 8196
name: Ubutor
net0: virtio=A6:21:9C:69:FB:CE,bridge=vmbr0
net1: virtio=06:63:F9:1F:07:0E,bridge=vmbr1
numa: 0
ostype: l26
smbios1: uuid=da69726c-87ed-4427-9bf6-d2c95515bdf4
sockets: 1
virtio0: local:200/vm-200-disk-1.raw,format=raw,size=60G

 

[wolfgang]

What you try to do is not possible with this setup.
The Linux bridge filter the VLan tags.

You have 2 options
dedicate nic for the vm (pass thought).
or OpenVSwitch in promiscuous mode.

 

[brucexx]

I am not sure if I understand, there should be no VLAN tags , this is an access port the VLAN tag is stripped before it get out on this port. As far as I know, and I can confirm that today there should be no VLAN tag on the forwarded traffic , traffic that is going to the destination port to which I am connecting the VM.

How do I do the pass through ? Can you point me to some documentation ? Is it possible on PVE 3.4 ?