Ch12. 파드 스케줄링

apiVersion: v1
kind: Pod
metadata:
  name: kubernetes-nodeselector-pod
spec:
  containers:
  - name: kubernetes-nodeselector-pod
    image: arisu1000/simple-container-app:latest
    ports:
    - containerPort: 8080
  nodeSelector:
    disktype: hdd
YAML
복사
scheduling/nodeselector.yaml

위 yaml 파일을 apply 하면 파드 상태가 Pending이다. .spec.nodeSelector.disktype 필드 값 hdd는 노드 레이블의 설정인 ssd와 달라서 실행할 노드가 없기 때문이다.

따라서 hdd를 ssd로 변경 후 다시 실행한다.

apiVersion: v1
kind: Pod
metadata:
  name: kubernetes-nodeselector-pod
spec:
  containers:
  - name: kubernetes-nodeselector-pod
    image: arisu1000/simple-container-app:latest
    ports:
    - containerPort: 8080
  nodeSelector:
    disktype: ssd
YAML
복사
scheduling/nodeselector.yaml

12.2 어피니티와 안티 어피니티

12.2.1 노드 어피니티

apiVersion: v1
kind: Pod
metadata:
  name: kubernetes-nodeaffinity-pod
spec:
  containers:
  - name: kubernetes-nodeaffinity-pod
    image: arisu1000/simple-container-app:latest
    ports:
    - containerPort: 8080
  affinity:
    nodeAffinity:
      requiredDuringSchedulingIgnoredDuringExecution:
        nodeSelectorTerms:
        - matchExpressions:
          - key: beta.kubernetes.io/os
            operator: In
            values:
            - linux
            - window
          - key: disktype
            operator: Exists
          # - key: core
            # operator: Gt  
            # values: 
            # - "4"
      preferredDuringSchedulingIgnoredDuringExecution:
      - weight: 10
        preference:
          matchExpressions:
          - key: kubernetes.io/hostname
            operator: In
            values:
            - worker-node01
YAML
복사
scheduling/node-affinity.yaml

12.2.2 파드의 어피니티와 안티 어피니티

apiVersion: apps/v1
kind: Deployment
metadata:
  name: redis-cache
spec:
  selector:
    matchLabels:
      app: store
  replicas: 2
  template:
    metadata:
      labels:
        app: store
    spec:
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - store
            topologyKey: "kubernetes.io/hostname"
      containers:
      - name: redis-server
        image: redis:3.2-alpine
YAML
복사
scheduling/pod-antiaffinity.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-server
spec:
  selector:
    matchLabels:
      app: web-store
  replicas: 2
  template:
    metadata:
      labels:
        app: web-store
    spec:
      affinity:
        podAntiAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - web-store
            topologyKey: "kubernetes.io/hostname"
        podAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
          - labelSelector:
              matchExpressions:
              - key: app
                operator: In
                values:
                - store
            topologyKey: "kubernetes.io/hostname"
      containers:
      - name: web-app
        image: nginx:1.12-alpine
YAML
복사
scheduling/pod-antiaffinity.yaml