[Cloude] k8s- workload Resource = Controller

✔️ Workload Resource = Controller

파드의 집합

✔️ ReplicationController

• 파드의 복제본 개수 관리
• 컨트롤러에 의해서 관리되는 파드는 label이 붙어있어야함

myweb-rc.yaml

apiVersion: v1
kind: ReplicationController
metadata:
  name: myweb-rc
spec:
  replicas: 3
  selector:
    app: web
# Pod Configure
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
        - name: myweb
          image: ghcr.io/c1t1d0s7/go-myweb
          ports:
            - containerPort: 8080
              protocol: TCP

$ kubectl create -f myweb-rc.yaml

$ watch kubectl get rc,pods --show-labels -o wide

NAME                 READY   STATUS    RESTARTS   AGE   LABELS
pod/myweb-rc-7m4v7   1/1     Running   0          29m   app=web
pod/myweb-rc-7s4vp   1/1     Running   0          78m   app=web
pod/myweb-rc-jtq7d   1/1     Running   0          78m   app=web

$ kubectl label pod myweb-rc-jtq7d app=db --overwrite

$ kubectl label pod myweb-rc-jtq7d app=web --overwrite

✔️ RC 스케일링

명령형 커맨드

$ kubectl scale rc myweb-rc --replicas=5

명령형 오브젝트 구성

$ kubectl replace -f myweb-rc.yaml

$ kubectl patch -f myweb-rc.yaml -p '{"spec": {"replicas": 3}}'
$ kubectl patch rc myweb-rc.yaml --patch-file replicas.json

replicas.json

{"spec": {"replicas": 3}}

$ kubectl edit -f myweb-rc.yaml
$ kubectl edit rc myweb-rc
$ kubectl edit rc/myweb-rc

선언형 오브젝트 구성

$ kubectl apply -f myweb-rc.yaml

✔️ ReplicaSets

ReplicationController -> ReplicaSets

apiVersion: apps/v1
kind: ReplicaSets
metadata:
  name: myweb-rs
spec:
  replicas: 3
  selector:
    matchLabels:
      app: web
      env: dev
  template:
    metadata:
      labels:
        app: web
        env: dev
    spec:
      containers:
        - name: myweb
          image: ghcr.io/c1t1d0s7/go-myweb
          ports:
            - containerPort: 8080
              protocol: TCP
              

apiVersion: apps/v1
kind: ReplicaSet
metadata:
  name: myweb-rs-set
spec:
  replicas: 3
  selector:
    matchExpressions:
      - key: app
        operator: In
        values: 
          - web
      - key: env
        operator: Exists
  template:
    metadata:
      labels:
        app: web
        env: dev
    spec:
      containers:
        - name: myweb
          image: ghcr.io/c1t1d0s7/go-myweb
          ports:
            - containerPort: 8080
              protocol: TCP
              

$ cd ~/kubespray

✔️ Job

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