replica issue

repro1.yaml

kind: Deployment
# repro1.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: demo
  namespace: default
spec:
  replicas: 2
  # in next apply we'll remove this replicas property
  strategy: { "type": "RollingUpdate", "rollingUpdate": { "maxUnavailable": 1 } }
  selector: { "matchLabels": { "app": "demo" } }
  template:
    metadata: { "labels": { "app": "demo" } }
    spec:
      containers:
        - image: alpine
          name: noop
          command: ["sh -c 'while true; do sleep 1; done'"]

repro2.yaml

# repro2.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: demo
  namespace: default
spec:
  # replicas: 2 is now removed, it will default to 1 and overwrite the runtime value of 2
  strategy: { "type": "RollingUpdate", "rollingUpdate": { "maxUnavailable": 1 } }
  selector: { "matchLabels": { "app": "demo" } }
  template:
    metadata: { "labels": { "app": "demo" } }
    spec:
      containers:
        - image: alpine
          name: noop
          command: ["sh -c 'while true; do sleep 1; done'"]