[DOCS] Add CAPI KubeVirt example

docs/capi-kubevirt.md

@@ -0,0 +1,172 @@
+# Cluster API - Kubevirt
+
+This example demonstrates how k0smotron can be used with CAPK (Cluster API Provider Kubevirt).
+
+## Preparations
+
+Before starting this example, ensure that you have met the [general prerequisites](capi-examples.md#prerequisites). 
+
+To install the latest stable version of Kubevirt you can run:
+
+```bash
+export VERSION=$(curl -s https://storage.googleapis.com/kubevirt-prow/release/kubevirt/kubevirt/stable.txt)
+kubectl create -f https://github.com/kubevirt/kubevirt/releases/download/${VERSION}/kubevirt-operator.yaml
+kubectl create -f https://github.com/kubevirt/kubevirt/releases/download/${VERSION}/kubevirt-cr.yaml
+```
+
+To initialize the management cluster with Kubevirt infrastructure provider you can run:
+
+```bash
+clusterctl init --core cluster-api --infrastructure kubevirt
+```
+
+For more details on Cluster API Provider Kubevirt see it's [docs](https://github.com/kubernetes-sigs/cluster-api-provider-kubevirt).
+
+## Nested Virtualization
+
+If your kubernetes nodes are able to support nested virtualization please make sure it is enabled. If your nodes are not able to support nested virtualization you can work around it by running the following.
+
+```bash
+kubectl -n kubevirt patch kubevirt kubevirt --type=merge --patch '{"spec":{"configuration":{"developerConfiguration":{"useEmulation":true}}}}'
+```
+
+## Creating a child cluster
+
+Once all the controllers are up and running, you can apply the cluster manifests containing the specifications of the cluster you want to provision.
+
+Here is an example:
+
+```yaml
+apiVersion: cluster.x-k8s.io/v1beta1
+kind: Cluster
+metadata:
+  name: kubevirt-test
+spec:
+  clusterNetwork:
+    pods:
+      cidrBlocks:
+      - 192.168.0.0/16
+    serviceDomain: cluster.local
+    services:
+      cidrBlocks:
+      - 10.128.0.0/12
+  controlPlaneRef:
+    apiVersion: controlplane.cluster.x-k8s.io/v1beta1
+    kind: K0smotronControlPlane
+    name: k0s-test-cp
+  infrastructureRef:
+    apiVersion: infrastructure.cluster.x-k8s.io/v1beta1
+    kind: KubevirtCluster
+    name: kubevirt-test
+---
+apiVersion: controlplane.cluster.x-k8s.io/v1beta1
+kind: K0smotronControlPlane # This is the config for the controlplane
+metadata:
+  name: k0s-test-cp
+spec:
+  version: v1.27.4-k0s.0
+  persistence:
+    type: emptyDir
+  service:
+    type: LoadBalancer
+---
+apiVersion: infrastructure.cluster.x-k8s.io/v1alpha1
+kind: KubevirtCluster
+metadata:
+  name: kubevirt-test
+  annotations:
+    cluster.x-k8s.io/managed-by: k0smotron
+spec:
+  controlPlaneServiceTemplate:
+    spec:
+      type: ClusterIP
+---
+apiVersion: cluster.x-k8s.io/v1beta1
+kind: MachineDeployment
+metadata:
+  name: kubevirt-md
+spec:
+  clusterName: kubevirt-test
+  replicas: 1
+  selector:
+    matchLabels:
+      cluster.x-k8s.io/cluster-name: kubevirt-test
+  template:
+    metadata:
+      labels:
+        cluster.x-k8s.io/cluster-name: kubevirt-test
+    spec:
+      clusterName: kubevirt-test
+      bootstrap:
+        configRef:
+          apiVersion: bootstrap.cluster.x-k8s.io/v1beta1
+          kind: K0sWorkerConfigTemplate
+          name: kubevirt-test-machine-config
+      infrastructureRef:
+        apiVersion: infrastructure.cluster.x-k8s.io/v1alpha1
+        kind: KubevirtMachineTemplate
+        name: kubevirt-test-mt
+      version: v1.27.4
+---
+apiVersion: infrastructure.cluster.x-k8s.io/v1alpha1
+kind: KubevirtMachineTemplate
+metadata:
+  name: kubevirt-test-mt
+spec:
+  template:
+    spec:
+      virtualMachineBootstrapCheck:
+        checkStrategy: ssh
+      virtualMachineTemplate:
+        spec:
+          runStrategy: Always
+          template:
+            spec:
+              domain:
+                cpu:
+                  cores: 1
+                devices:
+                  disks:
+                  - disk:
+                      bus: virtio
+                    name: containervolume
+                  networkInterfaceMultiqueue: true
+                memory:
+                  guest: 1Gi
+              evictionStrategy: External
+              volumes:
+              - containerDisk:
+                  image: quay.io/capk/ubuntu-2204-container-disk:v1.27.14
+                name: containervolume
+---
+apiVersion: bootstrap.cluster.x-k8s.io/v1beta1
+kind: K0sWorkerConfigTemplate
+metadata:
+  name: kubevirt-test-machine-config
+spec:
+  template:
+    spec:
+      version: v1.27.4+k0s.0
+      # More details of the worker configuration can be set here
+```
+
+After applying the manifests to the management cluster and confirming the infrastructure readiness, allow a few minutes for all components to provision. Once complete, your command line should display output similar to this:
+
+```bash
+% kubectl get cluster,machine
+NAME                                   PHASE         AGE     VERSION
+cluster.cluster.x-k8s.io/kubevirt-test Provisioned   22h   
+
+NAME                                               CLUSTER         NODENAME                  PROVIDERID                           PHASE     AGE     VERSION
+machine.cluster.x-k8s.io/kubevirt-md-mdvns-l2rxb   kubevirt-test   kubevirt-md-mdvns-l2rxb   kubevirt://kubevirt-md-mdvns-l2rxb   Running   22h     v1.27.4
+```
+
+You can also check the status of the cluster deployment with `clusterctl describe cluster`.
+
+## Accessing the workload cluster
+
+To access the child cluster we can get the kubeconfig for it with `clusterctl get kubeconfig kubevirt-test`. You can then save it to disk and/or import to your favorite tooling like [Lens](https://k8slens.dev)
+
+## Deleting the cluster
+
+For cluster deletion, do **NOT** use `kubectl delete -f my-kubevirt-cluster.yaml` as that can result in orphan resources. Instead, delete the top level `Cluster` object. This approach ensures the proper sequence in deleting all child resources, effectively avoid orphan resources.

mkdocs.yml

@@ -32,6 +32,7 @@ nav:
         - Hetzner Cloud: capi-hetzner.md
         - OpenStack: capi-openstack.md
         - Docker: capi-docker.md
+        - KubeVirt: capi-kubevirt.md
         - vSphere: capi-vsphere.md
         - Remote Machine with Teleport: capi-remotemachine-teleport.md
         - Remote Machine with Okta ASA: capi-remotemachine-okta-asa.md