Deploy Kubevirt DPDK Dataplane Support for VMs
SUMMARY Cloud-Native Contrail® Networking™ supports the deployment of the vRouter DPDK dataplane (Kubevirt) for high-performance VM and container networking in Kubernetes.
Kubevirt Overview
Kubevirt is an open-source Kubernetes project that enables the management (scheduling) of virtual machine (VM) workloads alongside container workloads within a Kubernetes cluster. Kubevirt provides a unified development platform where developers build, modify, and deploy applications residing in both application containers and VMs within a common, shared environment.
Kubevirt provides the following additional functions to your Kubernetes cluster by adding:
-
Other types of pods, or Custom Resource Definitions (CRDs), to the Kubernetes API server.
-
Controllers for cluster-wide logic to support the new types of pods.
-
Daemons for node-specific logic to support the new types of pods.
As a result of this new functionality, Kubevirt creates and manages
VirtualMachineInstance
(VMI) objects. VMIs contain a workload controller
called a VirtualMachine
(VM). The VM maintains the persistent state of its
VMI. This process enables users to terminate and initiate VMs at another time with no change
in data or state. Additionally, you can deploy Kubevirt on top of a Kubernetes cluster,
which lets you manage traditional container workloads along with VMIs managed by Kubevirt.
VMs have access to Kubernetes cluster features with no additional permissions required.
Kubevirt DPDK Implementation
Kubevirt does not typically support user space networking for fast packet processing. In
Cloud-Native Contrail Networking however, enhancements enable Kubevirt to support
vhostuser
interface types for VMs. These interfaces perform user space
networking with the Data Plane Development Kit (DPDK) vRouter and give pods access to the
increased performance and packet processing the DPDK vRouter provides.
Following are some of the benefits of the DPDK vRouter application:
-
Packet processing occurs in user space and bypasses kernel space. This bypass increases packet-processing efficiency.
-
Kernel interrupts and context switches do not occur because packets bypass kernel space. This bypass results in less CPU overhead and increased data throughput.
-
DPDK enhances the forwarding plane of the vRouter in user space, increasing performance.
-
DPDK Lcores run in poll mode. This mode enables the Lcores to receive and process packets immediately upon receiving them.
Deploy Kubevirt
Prerequisites
You must have an active Kubernetes cluster and the ability to use the
kubectl
client in order to deploy Kubevirt.
Pull Kubevirt Images and Deploy Kubevirt Using a Local Registry
See the following topic for information about how to deploy Kubevirt: Pull Kubevirt Images and Deploy Kubevirt Using a Local Registry.
These instructions are for the following Kubevirt releases:
-
v0.58.0 (current)
-
v0.48.0
Launch a VM Alongside a Container
With Kubevirt, launching and managing a VM in Kubernetes is similar to deploying a pod. You
can create a VM object using kubectl
. After creating a VM object, that VM
is active and running in your cluster.
Use the following high-level steps to launch a VM alongside a container:
-
Create a
VirtualNetwork
. -
Launch a VM.
Launch a VM
The following VirtualMachine
specs are examples of
VirtualMachine
instances with a varying number of interfaces.
- Single
vhostuser
interface VM:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-single-virtio namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-single-virtio app: vm-single-virtio-app spec: nodeSelector: master: master terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=
- Multi
vhostuser
interface:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-multi-virtio namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-multi-virtio app: vm-multi-virtio-app spec: nodeSelector: worker: worker terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} - name: vhost-user-vn-green vhostuser: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue - name: vhost-user-vn-green multus: networkName: vn-green volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=
- Bridge/
vhostuser
interface VM:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-virtio-veth namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-virtio-veth app: vm-virtio-veth-app spec: nodeSelector: master: master terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} - name: vhost-user-vn-green bridge: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue - name: vhost-user-vn-green multus: networkName: vn-green volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=
Create a Virtual Network
The following net-attach-def
object is an example of a virtual
network:
apiVersion: "k8s.cni.cncf.io/v1" kind: NetworkAttachmentDefinition metadata: name: vn-blue namespace: contrail annotations: juniper.net/networks: '{ "ipamV4Subnet": "19.1.1.0/24" }' labels: vn: vn-blue-vn-green spec: config: '{ "cniVersion": "0.3.1", "name": "nad-blue", "type": "contrail-k8s-cni" }'
Launch a VM
The following VirtualMachine
specs are examples of
VirtualMachine
instances with a varying number of interfaces:
- Single
vhostuser
interface VM:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-single-virtio namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-single-virtio app: vm-single-virtio-app spec: nodeSelector: master: master terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=
- Multi
vhostuser
interface:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-multi-virtio namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-multi-virtio app: vm-multi-virtio-app spec: nodeSelector: worker: worker terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} - name: vhost-user-vn-green vhostuser: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue - name: vhost-user-vn-green multus: networkName: vn-green volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=
- Bridge/
vhostuser
interface VM:apiVersion: kubevirt.io/v1 kind: VirtualMachine metadata: name: vm-virtio-veth namespace: contrail spec: running: true template: metadata: labels: kubevirt.io/size: small kubevirt.io/domain: vm-virtio-veth app: vm-virtio-veth-app spec: nodeSelector: master: master terminationGracePeriodSeconds: 30 domain: cpu: sockets: 1 cores: 8 threads: 2 #dedicatedCpuPlacement: true memory: hugepages: pageSize: "2Mi" resources: requests: memory: "512Mi" devices: disks: - name: containerdisk disk: bus: virtio - name: cloudinitdisk disk: bus: virtio interfaces: - name: default bridge: {} - name: vhost-user-vn-blue vhostuser: {} - name: vhost-user-vn-green bridge: {} useVirtioTransitional: true networks: - name: default pod: {} - name: vhost-user-vn-blue multus: networkName: vn-blue - name: vhost-user-vn-green multus: networkName: vn-green volumes: - name: containerdisk containerDisk: image: <image-repository> - name: cloudinitdisk cloudInitNoCloud: userDataBase64: SGkuXG4=