1.题目概述

• 添加一个sidecar容器（使用busybox镜像）到已有的pod 11-factor-app中
• 确保sidecar容器能够输出/var/log/11-factor-app.log的信息

• 使用volume挂载/var/log目录，确保sidecar能访问11-factor-app.log文件

  2.解析

• 通过kubectl get pod -o yaml的方法将pod备份，删除旧pod 11-factor-app

• copy一份新的yaml文件，添加一个名为sidecar的容器
• 新建emptyDir的卷，确保两个容器都挂载了/var/log目录
• 新建含有sidecar的pod，并通过kubectl logs验证

  3.参考答案

  3.1.备份pod

  kubectl get po 11-factor-app -o yaml > pod.yaml

  3.2.修改yaml

  apiVersion: v1
  kind: Pod
  metadata:
  name: 11-factor-app
  spec:
  containers:
  - name: 11-factor-app
    image: busybox
    args:
    - /bin/sh
    - -c
    - >
      i=0;
      while true;
      do
        echo "$i: $(date)" >> /var/log/11-factor-app.log;
        i=$((i+1));
        sleep 1;
      done      
    volumeMounts:
    - name: varlog
      mountPath: /var/log
  - name: sidecar
    image: busybox
    args: [/bin/sh, -c, 'tail -n+1 -f /var/log/11-factor-app.log']
    volumeMounts:
    - name: varlog
      mountPath: /var/log
  volumes:
  - name: varlog
    emptyDir: {}
  

  3.3.创建pod

  kubectl apply -f pod.yaml
  

  https://kubernetes.io/docs/concepts/cluster-administration/logging/