How to fix MinimumReplicasUnavailable in Kubernetes

kubectl get pods -o wide
kubectl get events --sort-by='.lastTimestamp'

kubectl top nodes  # Shows CPU/memory usage
kubectl describe nodes  # Shows resource allocations and pressures
kubectl get resourcequota -A  # Check namespace quotas

kubectl describe pod <pod-name>
kubectl logs <pod-name>  # Application logs
kubectl logs <pod-name> --previous  # Logs from crash

spec:
  containers:
  - name: app
    readinessProbe:
      httpGet:
        path: /health
        port: 8080
      initialDelaySeconds: 30  # Wait 30s before first check
      timeoutSeconds: 5         # Allow 5s for response
      periodSeconds: 10         # Check every 10s
      failureThreshold: 3       # Fail after 3 failures
    livenessProbe:
      httpGet:
        path: /live
        port: 8080
      initialDelaySeconds: 60
      timeoutSeconds: 5
      periodSeconds: 15
      failureThreshold: 3

spec:
  imagePullSecrets:
  - name: regcred  # Must exist: kubectl create secret docker-registry regcred ...
  containers:
  - name: app
    image: private-registry.com/myapp:latest

docker pull myapp:tag

kubectl get pdb -A
kubectl describe pdb <pdb-name>

apiVersion: policy/v1
kind: PodDisruptionBudget
metadata:
  name: app-pdb
spec:
  maxUnavailable: 1  # Allow 1 pod unavailable during disruptions
  selector:
    matchLabels:
      app: myapp

kubectl get pod <pod-name> -o yaml | grep -A5 nodeSelector

affinity:
  nodeAffinity:
    requiredDuringSchedulingIgnoredDuringExecution:
      nodeSelectorTerms:
      - matchExpressions:
        - key: disktype
          operator: In
          values:
          - ssd  # Verify at least one node has this label