Use Network Attachment Definitions in a Container¶

Network attachment definitions can be referenced by name when creating a container. The extended resource name of the SR-IOV pool should also be referenced in the resource requests.

About this task

The following examples use network attachment definitions net2 and net3 created in Creating Network Attachment Definitions.

As shown in these examples, it is important that you request the same number of devices as you have network annotations.

Procedure

Create a container with one additional SR-IOV interface using the net2 network attachment definition.

Populate the configuration file pod1.yaml with the following contents.

apiVersion: v1
kind: Pod
metadata:
  name: pod1
  annotations:
    k8s.v1.cni.cncf.io/networks: '[
        { "name": "net2" },
        { "name": "net2" }
    ]'
spec:
  containers:
  - name: pod1
    image: centos/tools
    imagePullPolicy: IfNotPresent
    command: [ "/bin/bash", "-c", "--" ]
    args: [ "while true; do sleep 300000; done;" ]
    resources:
      requests:
        intel.com/pci_sriov_net_datanet_b: '1'
      limits:
        intel.com/pci_sriov_net_datanet_b: '1'

Apply the configuration to create the container.

~(keystone_admin)]$  kubectl create -f pod1.yaml
pod/pod1 created

After creating the container, an extra network device interface, net2, which uses one SR-IOV VF, will appear in the associated container(s).

Create a container with two additional SR-IOV interfaces using the net2 network attachment definition.

Populate the configuration file pod2.yaml with the following contents.

apiVersion: v1
kind: Pod
metadata:
  name: pod2
  annotations:
    k8s.v1.cni.cncf.io/networks: '[
        { "name": "net2" }
    ]'
spec:
  containers:
  - name: pod2
    image: centos/tools
    imagePullPolicy: IfNotPresent
    command: [ "/bin/bash", "-c", "--" ]
    args: [ "while true; do sleep 300000; done;" ]
    resources:
      requests:
        intel.com/pci_sriov_net_datanet_b: '2'
      limits:
        intel.com/pci_sriov_net_datanet_b: '2'

Apply the configuration to create the container.

~(keystone_admin)$ kubectl create -f pod2.yaml
pod/pod2 created

After creating the container, network device interfaces net2 and net3, which each use one SR-IOV VF, will appear in the associated container(s).

Create a container with two additional SR-IOV interfaces using the net2 and net3 network attachment definitions.

Populate the configuration file pod3.yaml with the following contents.

apiVersion: v1
kind: Pod
metadata:
   name: pod3
   annotations:
      k8s.v1.cni.cncf.io/networks: '[
            { "name": "net2" },
            { "name": "net3" }
         ]'
spec:
  containers:
  - name: pod3
    image: centos/tools
    imagePullPolicy: IfNotPresent
    command: [ "/bin/bash", "-c", "--" ]
    args: [ "while true; do sleep 300000; done;" ]
    resources:
      requests:
         intel.com/pci_sriov_net_datanet_b: '2'
      limits:
         intel.com/pci_sriov_net_datanet_b: '2'

Apply the configuration to create the container.

~(keystone_admin)$  kubectl create -f pod3.yaml

net2 and net3 will each take a device from the pci_sriov_net_datanet_b pool and be configured on the container/host based on the their respective NetworkAttachmentDefinition specifications (see Creating Network Attachment Definitions).

After creating the container, network device interfaces net2 and net3, which each use one SR-IOV VF, will appear in the associated container(s).

Note

In the above examples, the PCI addresses allocated to the container are exported via an environment variable. For example:

~(keystone_admin)$  kubectl exec -n default -it pod3 -- printenv
                    PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
                    HOSTNAME=pod3
                    TERM=xterm
                    PCIDEVICE_INTEL_COM_PCI_SRIOV_NET_DATANET_B=0000:81:0e.4,0000:81:0e.0
                    KUBERNETES_PORT_443_TCP_PROTO=tcp
                    KUBERNETES_PORT_443_TCP_PORT=443
                    KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
                    KUBERNETES_SERVICE_HOST=10.96.0.1
                    KUBERNETES_SERVICE_PORT=443
                    KUBERNETES_SERVICE_PORT_HTTPS=443
                    KUBERNETES_PORT=tcp://10.96.0.1:443
                    KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
                    container=docker
                    HOME=/root

Create a container with two additional SR-IOV interfaces using the net1 network attachment definition for a DPDK based application.

The configuration of the SR-IOV host interface to which the datanetwork is assigned determines whether the network attachment in the container will be kernel or userspace-based. The SR-IOV host interface needs to be created with a vfio vf-driver for the network attachment in the container to be userspace-based, otherwise it will be kernel-based (netdevice).

Only netdevice is supported for Mellanox NICs.

Populate the configuration file pod4.yaml with the following contents.

apiVersion: v1
kind: Pod
metadata:
  name: testpmd
  annotations:
    k8s.v1.cni.cncf.io/networks: '[
            { "name": "net1" },
            { "name": "net1" }
    ]'
spec:
  restartPolicy: Never
  containers:
  - name: testpmd
    image: "amirzei/mlnx_docker_dpdk:ubuntu16.04"
    volumeMounts:
    - mountPath: /mnt/huge-1048576kB
      name: hugepage
    stdin: true
    tty: true
    securityContext:
      privileged: false
      capabilities:
        add: ["IPC_LOCK", "NET_ADMIN", "NET_RAW"]
    resources:
      requests:
        memory: 10Gi
        intel.com/pci_sriov_net_datanet_a: '2'
      limits:
        hugepages-1Gi: 4Gi
        memory: 10Gi
        intel.com/pci_sriov_net_datanet_a: '2'
  volumes:
  - name: hugepage
    emptyDir:
      medium: HugePages

Note

You must convert any dashes (-) in the datanetwork name used in the NetworkAttachmentDefinition to underscores (_).

Apply the configuration to create the container.

~(keystone_admin)$  kubectl create -f pod4.yaml
pod/testpmd created

Use Network Attachment Definitions in a Container

Use Network Attachment Definitions in a Container¶

StarlingX R6.0