schedule-on-master-node-affinity.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: red
  name: red
spec:
  replicas: 3
  selector:
    matchLabels:
      app: red
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: red
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: node-role.kubernetes.io/master
                operator: Exists
      containers:
      - image: nginx
        name: nginx
        resources: {}
status: {}