Simulating a daemonset with a deployment

deploy_daemonset_hpa.yaml

apiVersion: autoscaling/v2beta1
kind: HorizontalPodAutoscaler
metadata:
  name: nginx
spec:
  minReplicas: 1
  maxReplicas: 10000
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: nginx
  metrics:
    - type: External
      external:
        metricName: kubernetes_state.nodes.by_condition
        metricSelector: 
          matchLabels:
            kubernetescluster: "throwaway-dev-meeting"
            condition: "ready"
            status: "true"
        targetAverageValue: 1
---
apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
      annotations:
        ad.datadoghq.com/nginx.check_names: '["nginx"]'
        ad.datadoghq.com/nginx.init_configs: '[{}]'
        ad.datadoghq.com/nginx.instances: '[{"nginx_status_url": "http://%%host%%/nginx_status", "tags": "%%tags%%"}]'
        ad.datadoghq.com/nginx.logs: '[{"type": "docker","image": "nginx","service": "nginx","source": "nginx"}]'
    spec:
      affinity:
        podAntiAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
          - weight: 100
            podAffinityTerm:
              labelSelector:
                matchExpressions:
                - key: app
                  operator: In
                  values:
                  - nginx
              topologyKey: "kubernetes.io/hostname"
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - name: http
          containerPort: 80