Bits of .NET

Rolling updates can accidentally take down too many pods. PDB guarantees minimum availability.

Create PDB:

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: myapp-pdb
spec:
  minAvailable: 2  # Always keep at least 2 pods running
  selector:
    matchLabels:
      app: myapp

Or Use maxUnavailable:

spec:
  maxUnavailable: 1  # At most 1 pod can be down at a time
  selector:
    matchLabels:
      app: myapp

Apply:

kubectl apply -f pdb.yaml

# Check PDB status
kubectl get pdb

What Happens:
Node drain during maintenance → Kubernetes checks PDB → Won’t evict pod if it would violate minimum availability

Zero downtime during cluster maintenance!