802.1Q Double-Tagging
This section describes the configuration of 802.1Q double-tagging support to the hypervisor per Virtual Function (VF). The Virtual Machine (VM) attached to the VF (via SR-IOV) can send traffic with or without C-VLAN. Once a VF is configured to VST encapsulation, the adapter's hardware will insert C-VLAN to any packet from the VF to the physical port. On the receive side, the adapter hardware will strip the C-VLAN from any packet coming from the wire to that VF.
- Add the required C-VLAN tag (on the hypervisor) per port per VF. There are two ways to add the C-VLAN: - By using sysfs: - echo - '100:0:802.1q'> /sys/- class/net/ens1f0/device/sriov/- 0/vlan
- By using the ip link command (available only when using the latest Kernel version): - ip link set dev ens1f0 vf - 0vlan- 100- Check the configuration using the ip link show command: - # ip link show ens1f0 ens1f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu - 1500qdisc mq state UP mode DEFAULT qlen- 1000link/ether ec:0d:9a:- 44:- 37:- 84brd ff:ff:ff:ff:ff:ff vf- 0MAC- 00:- 00:- 00:- 00:- 00:- 00, vlan- 100, spoof checking off, link-state auto, trust off vf- 1MAC- 00:- 00:- 00:- 00:- 00:- 00, spoof checking off, link-state auto, trust off vf- 2MAC- 00:- 00:- 00:- 00:- 00:- 00, spoof checking off, link-state auto, trust off vf- 3MAC- 00:- 00:- 00:- 00:- 00:- 00, spoof checking off, link-state auto, trust off vf- 4MAC- 00:- 00:- 00:- 00:- 00:- 00, spoof checking off, link-state auto, trust off
 
- Create a VLAN interface on the VM and add an IP address. - # ip link add link ens5 ens5. - 40type vlan protocol- 802.1q id- 40# ip addr add- 42.134.- 135.7/- 16brd- 42.134.- 255.255dev ens5.- 40# ip link set dev ens5.- 40up
- To verify the setup, run ping between the two VMs and open Wireshark or tcpdump to capture the packet.