应用程序未使用 Kubernetes 正确部署

Question

我开发了一个 Spring 引导应用程序，我使用 docker-compose 来创建我的容器。对于 Kubernetes，我通过 minikubes 使用了 kompose。我将图像推送到 docker hub，并尝试用两种方式部署我的容器

kompose up

和

kompose convert -f docker-compose.yaml kubectl create -f (deplymentfiles)

但是我收到了这个回复

WARN Volume mount on the host "/home/App/src/main/docker/postgres-data" isn't supported - ignoring path on the host 
INFO We are going to create Kubernetes Deployments, Services and PersistentVolumeClaims for your Dockerized application. If you need different kind of resources, use the 'kompose convert' and 'kubectl create -f' commands instead. 

INFO Deploying application in "default" namespace 
INFO Successfully created Service: adminer        
INFO Successfully created Service: app            
INFO Successfully created Service: mypostgres     
INFO Successfully created Deployment: adminer     
INFO Successfully created Deployment: app         
INFO Successfully created Deployment: mypostgres  
INFO Successfully created PersistentVolumeClaim: mypostgres-claim0 of size 100Mi. If your cluster has dynamic storage provisioning, you don't have to do anything. Otherwise you have to create PersistentVolume to make PVC work

当我运行kubectl get pods

NAME                           READY     STATUS             RESTARTS   AGE
adminer-6cd96f8846-69qb8       1/1       Running            0          2m
app-5796c489ff-m46xk           0/1       ImagePullBackOff   0          2m
mypostgres-649865b4d8-nhglj    1/1       Running            0          2m

kubectl describe pod app-5796c489ff-m46xk

显示这个

Name:           app-5796c489ff-m46xk
Namespace:      default
Node:           minikube/192.168.99.100
Start Time:     Mon, 11 Jun 2018 11:02:32 +0200
Labels:         io.kompose.service=app
                pod-template-hash=1352704599
Annotations:    <none>
Status:         Pending
IP:             172.17.0.3
Controlled By:  ReplicaSet/app-5796c489ff
Containers:
  app:
    Container ID:   
    Image:          iroolapp
    Image ID:       
    Port:           8086/TCP
    Host Port:      0/TCP
    State:          Waiting
      Reason:       ImagePullBackOff
    Ready:          False
    Restart Count:  0
    Environment:
      DATABASE_HOST:      mypostgres
      DATABASE_NAME:      test
      DATABASE_PASSWORD:  root
      DATABASE_PORT:      5432
      DATABASE_USER:      root
    Mounts:
      /var/run/secrets/kubernetes.io/serviceaccount from default-token-wdb8n (ro)
Conditions:
  Type           Status
  Initialized    True 
  Ready          False 
  PodScheduled   True 
Volumes:
  default-token-wdb8n:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  default-token-wdb8n
    Optional:    false
QoS Class:       BestEffort
Node-Selectors:  <none>
Tolerations:     <none>
Events:
  Type     Reason                 Age              From               Message
  ----     ------                 ----             ----               -------
  Normal   Scheduled              3m               default-scheduler  Successfully assigned app-5796c489ff-m46xk to minikube
  Normal   SuccessfulMountVolume  3m               kubelet, minikube  MountVolume.SetUp succeeded for volume "default-token-wdb8n"
  Normal   Pulling                1m (x4 over 3m)  kubelet, minikube  pulling image "iroolapp"
  Warning  Failed                 1m (x4 over 3m)  kubelet, minikube  Failed to pull image "iroolapp": rpc error: code = Unknown desc = Error response from daemon: pull access denied for iroolapp, repository does not exist or may require 'docker login'
  Warning  Failed                 1m (x4 over 3m)  kubelet, minikube  Error: ErrImagePull
  Normal   BackOff                1m (x6 over 3m)  kubelet, minikube  Back-off pulling image "iroolapp"
  Warning  Failed                 1m (x6 over 3m)  kubelet, minikube  Error: ImagePullBackOff

最后这是我的 docker-compose 文件

version: '3'
services:
  app:
    image: iroolapp
    depends_on:
    - mypostgres
    ports:
     - "9000:8086"
    environment:
      - DATABASE_HOST=mypostgres
      - DATABASE_USER=root
      - DATABASE_PASSWORD=root
      - DATABASE_NAME=test
      - DATABASE_PORT=5432

    networks:
        default:

  mypostgres:
    image: postgres:9.6-alpine
    container_name: mypostgres

    ports:
     - "5433:5432"


    environment:
     - POSTGRES_PASSWORD=root
     - POSTGRES_USER=root
     - POSTGRES_DB=irooldb
    volumes:
    - ./postgres-data:/var/lib/postgresql/data

  adminer:
    image: adminer
    ports:
      - 8080:8080
    networks:
        default:

networks:
   default:
      external:
        name: mynetwork

我的问题是：ImagePullBackoff指的是什么？使用 kompose 是一个好方法吗？在使用 kubernetes

之前将图像推送到 docker hub 是必要的步骤吗

Answer 1

Q1

what does ImagePullBackoff refers to

从日志中可以看到多次尝试拉取镜像"iroolapp" pod app-5796c489ff-m46xk的容器需求（参见pod的container字段image）从注册表和所有失败。 ImagePullBackoff 发生在这些失败之后。

Q2

using kompose is it a good approach?

没用过...

Q3

and is it a necessary step to push images to docker hub before using kubernetes

不是。如果只是为了简单测试，您可以通过将 imagePullPolicy 设置为 IfNotPreset 或 Never 来使用本地图像（确保图像已加载）。或者，您可以拥有自己的私人注册表。

Answer 2

ImagePullBackoff表示无法获取图片

你真的看过错误信息了吗？它说 Failed to pull image "iroolapp": rpc error: code = Unknown desc = Error response from daemon: pull access denied for iroolapp, repository does not exist or may require 'docker login'

您是否登录 docker 中心？ docker 中心里有你的图片吗？因为那是它试图拉取图像的地方。

Answer 3

我想通了，事实上，在我的 docker-compose 文件中，我应该指定图像引用在 docker 中心推送的存储库中发布的图像：

image: docker.io/<dockerHub username>/<imagename>

Answer 4

我认为图像名称根本没有得到正确的方向。如果您存储在您的回购协议中，请提供完整路径，如 "username/repo:tag" 或首先在终端 "docker search imagename" 中通过命令搜索。 Kubernetes 一次又一次地拉取图像直到运行条件，所以可能是 RESTART 计数变高了。所以给它正确的 url 或私人回购路径。

应用程序未使用 Kubernetes 正确部署

Application not properly deployed using Kuberenetes

docker

kubernetes

docker-compose

kompose