revisit sriov support

[sunya-ch]

spec:
  subnet: "172.34.0.0/16"
  ipam: |
    {
      "type": "multi-nic-ipam",
      "hostBlock": 8,
      "interfaceBlock": 2,
      "vlanMode": "l2"
    }
  multiNICIPAM: true
  plugin:
    cniVersion: "0.3.0"
    type: sriov
    args:
      numVfs: "2"
      isRdma: "true"

Sample MultiNicNetwork

How it works?

Requires sriov-operator to operate configuration

Controller automatically generate NetworkAttachmentDefinition (NAD)

The important function is GetConfig function

It does the following steps:

• 1. create a new SriovNetworkPolicy (new resource name generated from MultiNicNetwork name) if the resourceName is not defined in args.
     • The policy is created from the provided args including priority, mtu, numVfs, isRdma, needVhostNet
     • The policy will automatically add the rootDevices field from the network address defined in spec.masterNets if exists
• 2. create SriovNetwork --> this SriovNetwork will be operated by sriov operator and generate a different NAD
• 3. render NAD from the sriovnet and add resource name from the step in annotations.

The key is step 1 and step 3.

Note that, step 2 might not require the creation to the API server. Need to check whether sriov operator does anything else more than just creating a NAD.

The functionalities of Muti-NIC CNI for SR-IoV use case is that,

1. Auto generate sriovnetwork policy and corresponding NAD by list of network addresses (single point of definition)
2. Apply Multi-NIC IPAM to compute host-interface range CIDR which allow applying L3 policy on each interface

---

Tasks

• Try sample SR-IOV MultiNicNetwork
• Check compatibility to SR-IOV operator
• Update controller or CNI as needed
• Add sample use case with predefined resource name and test
• Revisit this folder: https://github.com/foundation-model-stack/multi-nic-cni/tree/main/config/samples/sv-iov

[sunya-ch]

Need Results:

• generated SriovNetwork CR yaml

# [root@bcmt-baseos multi-nic-cni]# oc get sriovnetwork -o yaml
apiVersion: v1
items:
- apiVersion: sriovnetwork.openshift.io/v1
  kind: SriovNetwork
  metadata:
    annotations:
      operator.sriovnetwork.openshift.io/last-network-namespace: openshift-sriov-network-operator
    creationTimestamp: "2025-07-23T19:31:18Z"
    finalizers:
    - netattdef.finalizers.sriovnetwork.openshift.io
    generation: 1
    labels:
      multi-nic-cni-generated: "true"
    name: multinic-sriov-net
    namespace: openshift-sriov-network-operator
    resourceVersion: "84074927"
    uid: 8af87330-eed5-4a31-aed6-ee8ab140b1c1
  spec:
    logLevel: info
    resourceName: multinicsriov
    vlan: 1134
kind: List
metadata:
  resourceVersion: ""

• generated NAD by SRIOV operator

# [root@bcmt-baseos multi-nic-cni]# oc get net-attach-def multinic-sriov-net -o yaml
apiVersion: k8s.cni.cncf.io/v1
kind: NetworkAttachmentDefinition
metadata:
  annotations:
    k8s.v1.cni.cncf.io/resourceName: openshift.io/multinicsriov
  creationTimestamp: "2025-07-23T19:31:18Z"
  generation: 1
  name: multinic-sriov-net
  namespace: openshift-sriov-network-operator
  resourceVersion: "84074926"
  uid: 51ebaa2b-4aa4-4605-a3f1-889fc5f89d2c
spec:
  config: |-
    {
        "cniVersion": "1.0.0",
        "name": "multinic-sriov-net",
        "type": "sriov",
        "vlan": 1134,
        "vlanQoS": 0,
        "logLevel": "info",
        "ipam": {}
    }

• generated NAD by multi-nic-cni operator

# [root@bcmt-baseos multi-nic-cni]# oc get net-attach-def multinic-sriov -o yaml
apiVersion: k8s.cni.cncf.io/v1
kind: NetworkAttachmentDefinition
metadata:
  annotations:
    k8s.v1.cni.cncf.io/resourceName: openshift.io/multinicsriov
  creationTimestamp: "2025-07-23T19:31:24Z"
  generation: 2
  labels:
    multi-nic-cni-generated: "true"
  name: multinic-sriov
  namespace: openshift-sriov-network-operator
  ownerReferences:
  - apiVersion: multinic.fms.io/v1
    blockOwnerDeletion: true
    controller: true
    kind: MultiNicNetwork
    name: multinic-sriov
    uid: ff6a4129-5ccf-463b-8c5c-a9ef94514690
  resourceVersion: "84075294"
  uid: 62863b37-49b1-45a8-a1c3-b13f08a7a45f
spec:
  config: '{"cniVersion":"0.3.0","name":"multinic-sriov","type":"multi-nic","ipam":{"hostBlock":8,"interfaceBlock":2,"type":"multi-nic-ipam","vlanMode":"l2"},"dns":{},"plugin":{"cniVersion":"0.3.1","type":"sriov","vlan":0},"subnet":"172.34.0.0/16","masterNets":["172.12.0.0/16"],"multiNICIPAM":true,"daemonIP":"","daemonPort":11000}'

So,

• we need to figure it out why rendered config in multi-nic-cni is missing param from sriov network.
  Reference to source: https://github.com/k8snetworkplumbingwg/sriov-network-operator/blob/023a4b3558a7b4394c5791d308c8ab190db64701/api/v1/helper.go#L709
• try to replace manual duplication with https://pkg.go.dev/github.com/k8snetworkplumbingwg/sriov-network-operator

[sunya-ch]

Tasks:

• Fix NAD configuration overriden chore: sriov validation #312
• Fix IP address for VF Assign IP address for VF based on PF for multi-nic-ipam #313
• Confirm make concheck for SRIOV
• (low priority) Try removing SriovNetwork creation

  multi-nic-cni/internal/plugin/sriov.go

  Line 216 in 81ba74c

  err = p.SriovNetworkHandler.Create(SRIOV_NAMESPACE, sriovnet, result)