monitoring

VirtLauncherPodsStuckFailed

Meaning

This alert fires when a large number of virt-launcher Pods remain in Failed phase.

Condition: cluster:kubevirt_virt_launcher_failed:count >= 200 for 10 minutes Virt-launcher Pods host VM workloads and mass failures can indicate migration loops, image/network/storage issues, or control-plane regressions.

Impact

VMs and the cluster control plane may be affected:

Diagnosis

  1. Confirm scope and distribution:
cluster:kubevirt_virt_launcher_failed:count
count by (namespace) (kube_pod_status_phase{phase="Failed", pod=~"virt-launcher-.*"} == 1)
count by (node) (
  (kube_pod_status_phase{phase="Failed", pod=~"virt-launcher-.*"} == 1)
  * on(pod) group_left(node) kube_pod_info{pod=~"virt-launcher-.*", node!=""}
)
topk(5, count by (reason) (kube_pod_container_status_last_terminated_reason{pod=~"virt-launcher-.*"} == 1))
  1. Sample failed Pods and events:
# List a few failed virt-launcher pods cluster-wide
kubectl get pods -A -l kubevirt.io=virt-launcher --field-selector=status.phase=Failed --no-headers | head -n 20
# Inspect events for a representative pod (image/CNI/storage/useful errors)
kubectl -n <namespace> describe pod <virt-launcher-pod> | sed -n '/Events/,$p'
  1. Check for migration storms:
kubectl get vmim -A
  1. Control plane and component logs (look for spikes/errors):
NAMESPACE="$(kubectl get kubevirt -A -o jsonpath='{.items[0].metadata.namespace}')"
kubectl -n "$NAMESPACE" logs -l kubevirt.io=virt-controller --tail=200
kubectl -n "$NAMESPACE" logs -l kubevirt.io=virt-handler --tail=200
  1. Infrastructure checks (common causes):

Mitigation

  1. Reduce blast radius:
kubectl delete vmim -A
  1. Clean up Failed Pods (relieves API/etcd and monitoring):
kubectl get pods -A -l kubevirt.io=virt-launcher --field-selector=status.phase=Failed -o name | xargs -r -n50 kubectl delete
  1. Resolve root cause:
  1. Validate resolution (alert clears):
cluster:kubevirt_virt_launcher_failed:count

Ensure the failed count drops and stays below threshold and that new virt-launcher Pods start successfully and VMIs are healthy.

If you cannot resolve the issue, see the following resources: