Chapter 1. Installing Container-native Virtualization

Container-native Virtualization is an add-on to OpenShift Container Platform that allows virtual machine workloads to run and be managed alongside container workloads. You can create virtual machines from disk images imported using the containerized data importer (CDI) controller, or from scratch within OpenShift Container Platform.

Container-native Virtualization introduces two new objects to OpenShift Container Platform:

With the Container-native Virtualization add-on, virtual machines run in pods and have the same network and storage capabilities as standard pods.

Existing virtual machine disks are imported into persistent volumes (PVs), which are made accessible to Container-native Virtualization virtual machines using persistent volume claims (PVCs). In OpenShift Container Platform, the virtual machine object can be modified or replaced as needed, without affecting the persistent data stored on the PV.

See the OpenShift Container Platform Installing Clusters Guide for planning considerations for different cluster configurations.

Binary builds and MiniShift are not supported with Container-native Virtualization.

Container-native Virtualization implements an admission controller as a webhook so that Container-native Virtualization-specific creation requests are forwarded to the webhook for validation. Registering webhooks must be enabled during installation of the OpenShift Container Platform cluster.

To register the admission controller webhook, add the following under the [OSEv3:vars] section in your Ansible inventory file during OpenShift Container Platform deployment:

openshift_master_admission_plugin_config={"ValidatingAdmissionWebhook":{"configuration":{"kind": "DefaultAdmissionConfig","apiVersion": "v1","disable": false}},"MutatingAdmissionWebhook":{"configuration":{"kind": "DefaultAdmissionConfig","apiVersion": "v1","disable": false}}}

CRI-O is the required container runtime for use with Container-native Virtualization.

See the OpenShift Container Platform 3.11 CRI-O Runtime Documentation for more information on using CRI-O.

Container-native Virtualization supports local volumes, block volumes, and Red Hat OpenShift Container Storage as storage backends.

Metrics are not required, but are a recommended addition to your OpenShift Container Platform cluster because they provide additional information about Container-native Virtualization resources.

See the OpenShift Container Platform Installing Clusters Guide for comprehensive information on deploying metrics in your cluster.

You must enable the rhel-7-server-cnv-1.4-tech-preview-rpms repository for the master to install the Container-native Virtualization packages.

$ subscription-manager repos --enable=rhel-7-server-cnv-1.4-tech-preview-rpms

The virtctl client utility is used to manage the state of the virtual machine, forward ports from the virtual machine pod to the node, and open console access to the virtual machine.

The kubevirt-ansible RPM contains the latest automation for deploying Container-native Virtualization. This procedure installs all Container-native Virtualization components to your OpenShift Container Platform cluster.

This procedure installs the following components:

You can uninstall Container-native Virtualization with the same ansible-playbook command you used for deployment if you change the apb_action parameter value to deprovision.

This procedure uninstalls the following components:

You can use this example to see how to modify your own Ansible inventory file to match your cluster configuration.

[OSEv3:children]
masters
nodes
etcd

[OSEv3:vars]
openshift_deployment_type=openshift-enterprise
ansible_ssh_user=root
ansible_service_broker_registry_whitelist=['.*-apb$']
ansible_service_broker_local_registry_whitelist=['.*-apb$']

# Enable admission controller webhooks
openshift_master_admission_plugin_config={"ValidatingAdmissionWebhook":{"configuration":{"kind": "DefaultAdmissionConfig","apiVersion": "v1","disable": false}},"MutatingAdmissionWebhook":{"configuration":{"kind": "DefaultAdmissionConfig","apiVersion": "v1","disable": false}}}

# CRI-O
openshift_use_crio=true

# Provide your credentials to consume the redhat.io registry
oreg_auth_user=$rhnuser
oreg_auth_password='$rhnpassword'

# Host groups
[masters]
master.example.com

[etcd]
master.example.com

[nodes]
master.example.com openshift_node_group_name='node-config-master-infra-crio'
node1.example.com openshift_node_group_name='node-config-compute-crio'
node2.example.com openshift_node_group_name='node-config-compute-crio'