SR-IOV

updated: 2020-07-05 00:39

SR-IOV¶

The purpose of this page is to describe how to enable SR-IOV functionality available in Kuryr-libnetwork. This page intends to serve as a guide for how to configure OpenStack Networking and Kuryr-libnetwork to create SR-IOV ports and leverage them for containers.

The basics¶

PCI-SIG Single Root I/O Virtualization and Sharing (SR-IOV) functionality is available in OpenStack since the Juno release. The SR-IOV specification defines a standardized mechanism to virtualize PCIe devices. This mechanism can virtualize a single PCIe Ethernet controller to appear as multiple PCIe devices. Each device can be directly assigned to an instance, bypassing the virtual switch layer. As a result, users are able to achieve low latency and near-line wire speed.

The following terms are used throughout this document:

Term	Definition
PF	Physical Function. The physical Ethernet controller that supports SR-IOV.
VF	Virtual Function. The virtual PCIe device created from a physical Ethernet controller.

Using SR-IOV interfaces¶

In order to enable SR-IOV, the following steps are required:

Create Virtual Functions (Compute)
Configure neutron-server (Controller)
Enable neutron sriov-agent (Compute)
Configure kuryr-libnetwork (Compute)

Create Virtual Functions (Compute)¶

Follow the session ‘Create Virtual Functions’ in the networking guide.

Configure neutron-server (Controller)¶

Follow the session ‘Configure neutron-server’ in the networking guide.

Enable neutron sriov-agent (Compute)¶

Follow the session ‘Enable neutron sriov-agent’ in the networking guide.

Configure kuryr-libnetwork (Compute)¶

On every compute node running the kuryr-libnetwork service, edit kuryr-libnetwork config file (e.g. /etc/kuryr/kuryr.conf). Add kuryr_libnetwork.port_driver.drivers.sriov to enabled_port_drivers under [DEFAULT] and add kuryr.lib.binding.drivers.hw_veb to enabled_drivers under [binding].
```
[DEFAULT]
enabled_port_drivers = kuryr_libnetwork.port_driver.drivers.veth, kuryr_libnetwork.port_driver.drivers.sriov

[binding]
enabled_drivers = kuryr.lib.binding.drivers.veth, kuryr.lib.binding.drivers.hw_veb
```
Restart the kuryr-libnetwork service.

Launching containers with SR-IOV ports¶

Once configuration is complete, you can launch containers with SR-IOV ports.

Get the id of the network where you want the SR-IOV port to be created:

$ net_id=`neutron net-show net04 | grep "\ id\ " | awk '{ print $4 }'`

Create a kuryr network by specifying the name of the neutron network. Replace 10.10.0.0/24 and 10.10.0.1 with the CIDR and gateway of the subnet where you want the SR-IOV port to be created:
```
$ docker network create -d kuryr --ipam-driver=kuryr --subnet=10.10.0.0/24 --gateway=10.10.0.1 \
    -o neutron.net.uuid=$net_id kuryr_net
```
Create the SR-IOV port. vnic_type=direct is used here, but other options include normal, direct-physical, and macvtap. The binding-profile is used by the Neutron SR-IOV driver [1]. Replace physnet2, 1137:0047, and 0000:0a:00.1 with the correct value of the VF device:
```
$ neutron port-create $net_id --name sriov_port --binding:vnic_type direct \
    --binding-profile '{"physical_network": "physnet2", "pci_vendor_info": "1137:0047", "pci_slot": "0000:0a:00.1"}'
```
Create the container. Specify the SR-IOV port’s IP address created in step two:
```
$ docker run -it --net=kuryr_net --ip=10.0.0.5 ubuntu
```

Reference¶

[1] https://specs.openstack.org/openstack/neutron-specs/specs/juno/ml2-sriov-nic-switch.html