KubeVirt on K3s Playground

A multi-node K3s cluster with KubeVirt preinstalled, ready to run virtual machines next to containers.

Machines

Included

K3s, KubeVirt, CDI, KubeVirt Manager, virtctl, kubectl, helm, k9s, Docker, noVNC, and a Tokyo Night zsh terminal on every machine.

Components

Tabs

Wait for the cluster

The playground opens once all three K3s nodes are Ready, but KubeVirt, CDI and KubeVirt Manager keep starting in the background for a few more minutes. Run these on dev-machine before creating any VM. Each command returns as soon as its component is ready.

Nodes:

kubectl get nodes

All three nodes must show Ready.

KubeVirt:

kubectl -n kubevirt wait kv kubevirt --for condition=Available --timeout=10m

CDI:

kubectl -n cdi wait cdi cdi --for condition=Available --timeout=10m

KubeVirt Manager:

kubectl -n kubevirt-manager rollout status deployment kubevirt-manager --timeout=10m

To see every component pod at once:

kubectl get pods -n kubevirt -o wide

kubectl get pods -n cdi

All pods must be Running with every container ready (for example 1/1).

Quick start

From dev-machine, create and start a small test VM:

kubectl apply -f https://kubevirt.io/labs/manifests/vm.yaml

virtctl start testvm

kubectl get vmi testvm -w

Wait for PHASE Running and READY True, then press Ctrl+C.

Serial console (exit with Ctrl+]):

virtctl console testvm

VM screen in the browser (VNC)

One command on dev-machine, with the VM running:

vm-vnc testvm

Then open the VM Screen tab. Press Ctrl+C in the terminal to stop.

For a VM in another namespace:

vm-vnc testvm my-namespace

vm-vnc does everything for you. It starts the KubeVirt VNC proxy and the browser bridge, and restarts the proxy after every session so reloading the tab reconnects. You never run virtctl vnc or websockify by hand.

vm-vnc stays in the foreground. Leave it running in one terminal tab and use another dev-machine terminal for other work.

Rules

• A VM accepts only one VNC session at a time. Do not run virtctl vnc by hand while vm-vnc is running, or the two keep disconnecting each other.
• Run one vm-vnc at a time. To switch VMs, press Ctrl+C and run vm-vnc with the other VM name.
• Cloud images such as CirrOS and AlmaLinux show a text login prompt, not a desktop. If the screen is black, click inside it and press Enter.

Troubleshooting

Limitations

iximiuz Labs playgrounds have no nested virtualization, so KubeVirt runs VMs with QEMU software emulation. Small images such as CirrOS boot in seconds, full distros take a few minutes.

containerDisk volumes are ephemeral. Anything written inside the VM is lost on every VM restart. Use a DataVolume on the local-path storage class for persistence.