啟動SR-IOV
===
# Install SR-IOV to server
* 首先我們需要有SR-IOV driver然後我們要使用intel i40e driver去enable SR-IOV，但也請選擇適合你網卡的driver，我用Intel Corporation I350 Gigabit Network Connection為例
### Install i40e driver

sudo apt install -y make gcc libelf-dev
I40E_VER=2.4.10
wget https://downloadmirror.intel.com/28306/eng/i40e-${I40E_VER}.tar.gz && \
tar xvzf i40e-${I40E_VER}.tar.gz && cd i40e-${I40E_VER}/src && sudo make install && cd -

### Update GRUB Settings

sudo sed -i '/GRUB_CMDLINE_LINUX_DEFAULT/c\GRUB_CMDLINE_LINUX_DEFAULT="intel_iommu=on"' /etc/default/grub
sudo sed -i '/GRUB_CMDLINE_LINUX/c\GRUB_CMDLINE_LINUX="intel_iommu=on"' /etc/default/grub
sudo update-grub

### Setup vfio-pci module auto-load on boot

echo 'vfio-pci' | sudo tee /etc/modules-load.d/vfio-pci.conf
wget -qO- https://fast.dpdk.org/rel/dpdk-17.11.2.tar.xz | sudo tar -xJC /opt
sudo mv /opt/dpdk-* /opt/dpdk

### Create SR-IOV Script for systemctl
* 我們會寫一source code到/opt/scripts/sriov.sh我們需要佈署server 就要執行

sudo mkdir -p /sriov-cni /opt/scripts
sudo su
cat << "EOF" > /opt/scripts/sriov.sh
#!/bin/bash
# Copied from infra/sriov.sh
# Usage: ./sriov.sh ens785f0

NUM_VFS=$(cat /sys/class/net/$1/device/sriov_totalvfs)
echo 0 | sudo tee /sys/class/net/$1/device/sriov_numvfs
echo $NUM_VFS | sudo tee /sys/class/net/$1/device/sriov_numvfs
sudo ip link set $1 up
for ((i = 0 ; i < ${NUM_VFS} ; i++ )); do ip link set $1 vf $i spoofchk off; done
for ((i = 0 ; i < ${NUM_VFS} ; i++ )); do ip link set dev $1 vf $i state enable; done
EOF
exit
# Script perms
sudo chmod 744 /opt/scripts/sriov.sh

* After we have the script, we can write a sriov.service to define a service and control this service by sudo systemctl enable sriov.

sudo su
# Systemd unit to run the above script
cat << "EOF" > /etc/systemd/system/sriov.service
[Unit]
Description=Create VFs for ens802f0

[Service]
Type=oneshot
ExecStart=/opt/scripts/sriov.sh ens802f0

[Install]
WantedBy=default.target
EOF
exit

# Enable the SRIOV systemd unit
sudo systemctl enable sriov