[CKA] 따배씨 - 14. init 컨테이너를 포함한 Pod 운영

문제

Cluster: kubectl config use-context k8s Perform the following Tasks: Add an init container to web-pod(which has been defined in spec file /data/cka/webpod.yaml). The init container should create an empty file named /workdir/data.txt If /workdir/data.txt is not detected, the Pod should exit. Once the spec file has been updated with the init container definition, the Pod should be created

문제 환경 구성 

#/data/cka/webpod.yaml
apiVersion: v1
kind: Pod
metadata:
  name: web-pod
spec:
  containers:
  - image: busybox:1.28
    name: main
    command: ['sh','-c','if [ !-f /workdir/data.txt ];then exit 1;else sleep 300;fi']
    volumeMounts:
    - mountPath: "/workdir"
      name: workdir
  volumes:
  - name: workdir
    emptyDir: {}

문제풀이

# 1.webpod.yaml 수정
vim /data/cka/webpod.yaml

....
apiVersion: v1
kind: Pod
metadata:
  name: web-pod
spec:
  containers:
  - image: busybox:1.28
    name: main
    command: ['sh','-c','if [ !-f /workdir/data.txt ];then exit 1;else sleep 300;fi']
    volumeMounts:
    - mountPath: "/workdir"
      name: workdir
  initContainers:
  - name: init-myservice
    image: busybox:1.28
    command: ['sh','-c','touch /workdir/data.txt']
    volumeMounts:
    - mountPath: "/workdir"
      name: workdir
  volumes:
  - name: workdir
    emptyDir: {}
    
 # 2. pod 업데이트 하기
 kubectl apply -f /data/cka/webpod.yaml

• Init Containers: https://kubernetes.io/docs/concepts/workloads/pods/init-containers/

Init Containers