指定调度节点

1、Pod.spec.nodeName 将 Pod 直接调度到指定的 Node 节点上，会跳过 Scheduler 的调度策略，该匹配规则是强制匹配

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myweb
spec:
  replicas: 8
  selector:
    matchLabels:
      app: myweb
  template:
    metadata:
      labels:
        app: myweb
    spec:
      nodeName: k8s-node01
      containers:
      - name: myweb-container
        image: wangyanglinux/myapp:v1
        ports:
        - containerPort: 80

2、Pod.spec.nodeSelector：通过 kubernetes 的 label-selector 机制选择节点，由调度器调度策略匹配 label，而后调度 Pod 到目标节点，该匹配规则属于强制约束

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myweb
spec:
  replicas: 2
  selector:
    matchLabels:
      app: myweb
  template:
    metadata:
      labels:
        app: myweb
    spec:
      nodeSelector:
        LABEL: LABEL-VALUE
      containers:
      - name: myweb
        image: wangyanglinux/myapp:v1
        ports:
        - containerPort: 80