8. Enable SR-IOV

8.1. Prerequisites

This guide assumes that you have installed Fuel and performed steps 5.3.1 - 5.3.9 from Installation Guide. To enable SR-IOV, you need a SRIOV-capable network PCI card. Also, only compute hosts can be configured with the``SRIOV`` role.

8.2. Features

  1. You can have multple VLANs inside one physical network
  2. When using Passthrough, as in SR-IOV scenario, OpenStack does not provides dhcp and metadata. You have to manage that manually or provide an additional network port with a regular OpenStack network.

8.3. SR-IOV Description

Quoting Mirantis blog post:

SR-IOV is a PCI Special Interest Group (PCI-SIG) specification for virtualizing network interfaces, representing each physical resource as a configurable entity (called a PF for Physical Function), and creating multiple virtual interfaces (VFs or Virtual Functions) with limited configurability on top of it, recruiting support for doing so from the system BIOS, and conventionally, also from the host OS or hypervisor. Among other benefits, SR-IOV makes it possible to run a very large number of network-traffic-handling VMs per compute without increasing the number of physical NICs/ports and provides means for pushing processing for this down into the hardware layer, off-loading the hypervisor and significantly improving both throughput and deterministic network performance.

8.4. Verify SR-IOV environment

To verify if network interface is SRIOV-capable and how many VFs are available, run the following command on the boostraped host:

lspci -s <bus ID> -vvv

8.5. Enable SR-IOV in Fuel

To enable SR-IOV in Fuel:

  1. Enable SR-IOV in plugin settings and configure a unique physnet name.

    _images/enable_sriov_settings.png

  1. Assign a SRIOV role to compute hosts.

    _images/enable_sriov_role_node.png

    Note

    SR-IOV will be enabled on all SR-IOV capable interfaces, not assigned to the Fuel bridges - the networks in Fuel web UI.

  1. You can modify the list of interfaces manually after deployment.

    _images/sriov_interfaces.png

  2. Deploy as in 5.3.10 Installation Guide

8.6. Create a virtual machine with SR-IOV device

To create a virtual machine with SR-IOV device:

  1. Create a VM with configured physical network and VLAN id:

    neutron net-create \
--provider:physical_network=<physical network from contrail settings tab> \
--provider: segmentation_id=<Vlan_id> <Network_Name>

  2. Create a subnet:

    neutron subnet-create <Network_name> <Subnet>

  3. Create a port:

    neutron port-create \
--fixed-ip subnet_id=<subnet uuid>,ip_address=<IP address from above subnet> \
--name <name of port> <vn uuid> --binding:vnic_type direct

  4. Boot the VM with the port:

    nova boot \
--flavor m1.large --image <image name> \
--nic port-id=<uuid of above port> <vm name>