Enable SR-IOV for Tungsten Fabric¶

This section instructs you on how to enable SR-IOV with the Neutron Tungsten Fabric (TF) back end.

To enable SR-IOV for TF:

Verify that your deployment meets the following requirements:
- NICs with the SR-IOV support are installed
- SR-IOV and VT-d are enabled in BIOS
Enable IOMMU in the kernel by configuring intel_iommu=on in the GRUB configuration file. Specify the parameter for compute nodes in BareMetalHostProfile in the grubConfig section:
```
spec:
  grubConfig:
    defaultGrubOptions:
      - 'GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX intel_iommu=on"'
```
Enable SR-IOV in the OpenStackDeployment CR through the node-specific overrides settings. For example:
```
spec:
  nodes:
    <NODE-LABEL>::<NODE-LABEL-VALUE>:
      features:
        neutron:
          sriov:
            enabled: true
            nics:
            - device: enp10s0f1
              num_vfs: 7
              physnet: tenant
```
Warning

After the OpenStackDeployment CR modification, the TF Operator generates a separate vRouter DaemonSet with specified settings. The tf-vrouter-agent-<XXXXX> pods will be automatically restarted on the affected nodes causing the network services interruption on virtual machines running on these hosts.

Optional. To modify a vRouter DaemonSet according to the SR-IOV definition in the OpenStackDevelopment CR, add vRouter custom specs to the TF Operator CR with the node label specified in the OpenStackDeployment CR. For example:

API v1alpha1

spec:
  controllers:
    tf-vrouter:
      agent:
        customSpecs:
        - name: sriov
          label:
            name: <NODE-LABEL>
            value: <NODE-LABEL-VALUE>
          containers:
          - name: agent
            env:
            - name: <VROUTER-GATEWAY>
              value: <VROUTER-GATEWAY-IP>

API v2 TechPreview Available since MOSK 24.1

spec:
  nodes:
    sriov:
      labels:
        name: <NODE-LABEL>
        value: <NODE-LABEL-VALUE>
      nodeVRouter:
        enabled: true
        envSettings:
          agent:
          - name: VROUTER_GATEWAY
            value: <VROUTER-GATEWAY-IP>