Installation guide

This section covers attaching Virtual Function to a guest as an additional network device.
SR-IOV requires Intel VT-d support.
Important
Xen requires additional kernel arguments to use SR-IOV. Modify the
/boot/grub/grub.conf file to enable SR-IOV. To enable SR-IOV with Xen for Intel systems
append the pci_pt_e820_access=on parameter to the kernel.
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.18-192.el5xen)
root (hd0,0)
kernel /xen.gz-2.6.18-192.el5 iommu=1
module /vmlinuz-2.6.18-192.el5xen ro root=/dev/VolGroup00/LogVol00
pci_pt_e820_access=on
module /initrd-2.6.18-192.el5xen.img
Pro ced u re 16 .1. At t ach an SR - IO V net wo rk d evice
1. En ab le In t el VT - d in BIO S an d in t h e kern el
Enable Intel VT-D in BIOS. See Procedure 15.1, “ Preparing an Intel system for PCI
passthrough” for more information on enabling Intel VT-d in BIOS and the kernel, or see your
system manufacturer's documentation for specific instructions.
2. Verif y su p po rt
Verify if the PCI device with SR-IOV capabilities are detected. This example lists an Intel
82576 network interface card which supports SR-IOV. Use the lspci command to verify if the
device was detected.
# lspci
03:00.0 Ethernet controller: Intel Corporation 82576 Gigabit Network
Connection (rev 01)
03:00.1 Ethernet controller: Intel Corporation 82576 Gigabit Network
Connection (rev 01)
Note
Note that the output has been modified to remove all other devices.
3. St art t h e SR- IO V kern el mo d u les
If the device is supported the driver kernel module should be loaded automatically by the
kernel. Optional parameters can be passed to the module using the modprobe command.
The Intel 82576 network interface card uses the igb driver kernel module.
⁠Chapt er 1 6 . SR- IO V
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