Kubernetes PodDisruptionBudget (PDB)

• https://kubernetes.io/docs/concepts/workloads/pods/disruptions/#pod-disruption-budgets
  • 1.4 Alpha, K8s v1.21 April 2021 GA, Eviction subresource 1.22
• https://github.com/kubernetes/enhancements/issues/85
• https://github.com/kubernetes/enhancements/tree/master/keps/sig-apps/85-Graduate-PDB-to-Stable
• https://kubernetes.io/docs/tasks/run-application/configure-pdb/

Commands

• kubectl get pdb

kubectl api-resources | grep -i pdb
poddisruptionbudgets              pdb          policy/v1                              true         PodDisruptionBudget

33m         Warning   CalculateExpectedPodCountFailed   poddisruptionbudget/xxxx-pdb                     Failed to calculate the number of expected pods: statefulsets.apps does not implement the scale subresource

kind: PodDisruptionBudget

55m         Normal    NoPods                            poddisruptionbudget/your_text                     No matching pods found

Test

kubectl drain ip-10-0-3-48.us-east-2.compute.internal --ignore-daemonsets
error when evicting pods/"your-pod-name" (will retry after 5s): Cannot evict pod as it would violate the pod's disruption budget

Examples

 apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
 name: zk-pdb
spec:
 minAvailable: 2
 selector:
   matchLabels:
     app: zookeeper

Related

• maxUnavailable
• NoPods
• Disruptions
• Karpenter
• spec.replicas
• Eviction API
• 1.21 Graceful node shutdown
• kubectl drain
• kubectl drain your-node-name --ignore-daemonsets
• TopologySpreadConstraints
• ttlSecondsUntilExpired

See also

• PodDisruptionBudget (PDB), kubernetes pod disruption budget v1
• kubectl get pods, -l, -n , Running, Pending, Init, ContainerCreating, ImagePullBackOff,Init:ImagePullBackOff, Terminating, ErrImagePull, Completed, InvalidImageName, kube-system, ls_containers.sh