1.题目

Create a pod name log, container name log-pro use image busybox, output the important information at /log/data/output.log. Then another container name log-cus use image busybox, load the output.log at /log/data/output.log and print it. Note, this log file only can be share within the pod.

2.解析

本题目考测pod概念和volume，题意是创建具有两个容器的pod，其中一个容器向/log/data/output.log写入一些信息，另外一个容器则要把该log文件加载到应用中并输出。需要注意的是，题目有说到这log文件仅允许在当前pod中使用，因此我们用emptyDir来解决问题。题目没有提及namespace，则默认选择default。

3.答案

1. 首先通过run命令输出yaml文件，再在其基础上修改

   kubectl run log --image=busybox --dry-run=client -oyaml > log-pod.yaml

   apiVersion: v1
   kind: Pod
   metadata:
   creationTimestamp: null
   labels:
    run: log
   name: log
   spec:
   containers:
   - image: busybox
    name: log
    resources: {}
   dnsPolicy: ClusterFirst
   restartPolicy: Always
   status: {}
   

2. 根据题目修改yaml

   apiVersion: v1
   kind: Pod
   metadata:
   creationTimestamp: null
   labels:
    run: log
   name: log
   spec:
   containers:
   - image: busybox
    name: log-pro
    resources: {}
    command: ["sh","-c","echo important information >> /log/data/output.log;sleep 1d"]
    volumeMounts:
    - name: data-log
      mountPath: /log/data
   - image: busybox
    name: log-cus
    command: ["sh","-c","cat /log/data/output.log;sleep 1d"]
    volumeMounts:
    - name: data-log
      mountPath: /log/data
   volumes:
   - name: data-log
   

3. 通过命令查看log-cus是否有print出期望的日志

   # 创建pod
   kubectl apply -f log.pod.yaml
   # 查看日志
   kubectl logs log -c log-cus
   # 查看容器内是否创建了log文件
   kubectl exec -it log -c log-pro -- cat /log/data/output.log