apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-load-balancer
  labels:
    app: nginx-load-balancer
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx-load-balancer
  template:
    metadata:
      labels:
        app: nginx-load-balancer
    spec:
      hostNetwork: false
      dnsPolicy: ClusterFirst
      # Prefer worker nodes only (not master nodes)
      affinity:
        nodeAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 100
            preference:
              matchExpressions:
              - key: node-role.kubernetes.io/master
                operator: DoesNotExist
          - weight: 50
            preference:
              matchExpressions:
              - key: node-role.kubernetes.io/control-plane
                operator: DoesNotExist
      containers:
      - name: nginx
        image: nginx:alpine
        ports:
        - containerPort: 8080
        volumeMounts:
        - name: html-content
          mountPath: /usr/share/nginx/html
        - name: nginx-config
          mountPath: /etc/nginx/conf.d
        resources:
          requests:
            memory: "64Mi"
            cpu: "100m"
          limits:
            memory: "128Mi"
            cpu: "200m"
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 30
          periodSeconds: 10
        readinessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 5
          periodSeconds: 5
      volumes:
      - name: html-content
        configMap:
          name: nginx-load-balancer-content
      - name: nginx-config
        configMap:
          name: nginx-load-balancer-nginx-config