PodDisruptionBudget (pdb)

A disruption refers to an event or action that causes a Pod to become unavailable or terminate. Disruptions can be voluntary or involuntary, depending on the cause

• It's a mechanism to ensure a minimum level of availability for Pods during voluntary pod disruptions (deletion)
• It sets limits on how many Pods from a specific set (e.g., in a Deployment, ReplicaSet, or StatefulSet) can be unavailable at the same time due to actions like:
• Node draining during maintenance.
• Cluster scaling.
• Upgrades initiated by administrators.

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: example-pdb
spec:
  selector:
    matchLabels:
      app: my-app
  minAvailable: 3
  maxUnavailable: 5 # mutually exclusive with minAvailable