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04 — Convert DisposableVm → MicroVM

Goal: Opt-in dual-run with fluxvm-microvm controller --convert so each DisposableVm projects a same-name MicroVM without a second POST /v1/vms.

1. Prerequisites​

  • fluxvm-kube + DisposableVm CRD installed (deploy/k8s/).
  • MicroVM CRDs installed (01 — Getting started).
  • Controller with --convert (not the default Deployment — you must add it).

Default deploy is convert-off:

kubectl -n fluxvm-system get deploy fluxvm-microvm-controller -o yaml \
  | grep -A2 'command:'
# expect: ["fluxvm-microvm", "controller"]   # no --convert

Enable for this lab:

kubectl -n fluxvm-system set command deploy/fluxvm-microvm-controller \
  -- fluxvm-microvm controller --convert
# or run locally:
fluxvm-microvm controller --convert

2. Create a DisposableVm​

kubectl apply -f - <<'EOF'
apiVersion: fluxvm.zyvor.io/v1
kind: DisposableVm
metadata:
  name: bridge-demo
  namespace: default
spec:
  node: <node-name>
  backend: qemu
  image: /var/lib/fluxvm/images/ubuntu.qcow2
  vcpus: 1
  memoryMib: 1024
  networkMode: user
  ttlSeconds: 300
EOF

Replace <node-name> with a capable node.

3. Watch the projected MicroVM​

kubectl get dvm bridge-demo
kubectl get mvm bridge-demo
kubectl get mvm bridge-demo -o jsonpath='{.metadata.annotations}' ; echo

Expect: a MicroVM named bridge-demo with:

  • microvm.fluxvm.zyvor.io/converted-from: disposablevm
  • microvm.fluxvm.zyvor.io/driven-by: fluxvm-kube (node agent skips VMM create)
  • persist: true, nodeName copied from the DisposableVm

4. Notes​

  • Conversion is a bridge for dual-running; prefer creating MicroVMs directly for new workloads that need scheduler placement.
  • Without driven-by=fluxvm-kube, dual-run would POST /v1/vms twice.
  • Deleting one side does not always delete the other — tear down both if you created both for a demo.
  • Ragnarok and other DisposableVm clients keep working; MicroVM is additive.

5. Cleanup​

kubectl delete dvm bridge-demo
kubectl delete mvm bridge-demo --ignore-not-found

Next​