Deploying with SR-IOV Support

TripleO can deploy Overcloud nodes with SR-IOV support. A new role ComputeSriov has been added to create a custom roles_data.yaml with composable SR-IOV role.

Execute below command to create the roles_data.yaml:

openstack overcloud roles generate -o roles_data.yaml Controller ComputeSriov

Once a roles file is created, the following changes are required:

  • Deploy Command

  • Parameters

  • Network Config

Deploy Command

Deploy command should include the generated roles data file from the above command.

Deploy command should also include the SR-IOV environment file to include the neutron-sriov-agent service. All the required parameters are also specified in this environment file. The parameters has to be configured according to the baremetal on which SR-IOV needs to be enabled.

Also, SR-IOV requires mandatory kernel parameters to be set, like intel_iommu=on iommu=pt on Intel machines. In order to enable the configuration of kernel parameters to the host, host-config-pre-network environment file has to be added for the deploy command.

Adding the following arguments to the openstack overcloud deploy command will do the trick:

openstack overcloud deploy --templates \
  -r roles_data.yaml \
  -e /usr/share/openstack-tripleo-heat-templates/environments/services/neutron-sriov.yaml \
  -e /usr/share/openstack-tripleo-heat-templates/environments/host-config-and-reboot.yaml \


Following are the list of parameters which need to be provided for deploying with SR-IOV support.

  • NovaPCIPassthrough: Provide the list of SR-IOV device names, the logical network, PCI addresses etc. The PF/VF devices matching the criteria would be available for guests.

  • NeutronPhysicalDevMappings: The map of logical network name and the physical interface.


    - devname: "p7p1"
      physical_network: "sriov1_net"
    - devname: "p7p2"
      physical_network: "sriov2_net"
  NeutronPhysicalDevMappings: "sriov1_net:p7p1,sriov2_net:p7p2"

The parameter KernelArgs should be provided in the deployment environment file, with the set of kernel boot parameters to be applied on the ComputeSriov role where SR-IOV is enabled:

    KernelArgs: "intel_iommu=on iommu=pt"

Network Config

SR-IOV supported network interfaces should be specified in the network config templates as sriov_pf type. This mechanism of configuring numvfs for SR-IOV device is recommended and NeutronSriovNumVFs shall be avoided.


  - type: sriov_pf
    name: p7p2
    mtu: 9000
    numvfs: 10
    use_dhcp: false
    defroute: false
    nm_controlled: true
    promisc: false