Kubernetes 部署“无法使用本地注册表、minikube 拉取镜像”

Question

尽管使用相同映像注册表的其他部署按预期工作，但我deployment在minikube本地注册表中收到“无法拉取映像”错误。

我的工作流程是从docker.collection如下所示的 Dockerfile 构建映像。

$ minikube start --insecure-registry localhost:5000 --memory 4096
$ docker build . -f docker.collection -t localhost:5000/collection:latest -t localhost:5000/collection:dev
$ docker push localhost:5000/collection
$ cat deployment.yaml | kubectl apply -f -

部署已根据需要创建，但 Pod 未启动，并且 minikube 仪表板显示：

无法拉取映像“localhost:5000/collection:dev”：rpc 错误：代码 = Unknown desc = 来自守护进程的错误响应：localhost:5000/collection:dev 未找到清单

我没有理由相信构建或推送映像有任何问题，并且在主机上，我可以成功拉取...

$ docker pull localhost:5000/collection:dev
dev: Pulling from collection
Digest: sha256:8becfdd412f0b86ece8335aa5ee1aede75992d17f88739a28da5939eab28fde5
Status: Image is up to date for localhost:5000/collection:dev

我还应该检查什么？如何获得有关失败的更多详细信息？

进一步调试

我也检查过：

• minikube 节点可以达到localhost:5000：

$ minikube ssh
$ ping localhost:5000
PING localhost:5000 (127.0.0.1): 56 data bytes
64 bytes from 127.0.0.1: seq=0 ttl=64 time=0.126 ms
64 bytes from 127.0.0.1: seq=1 ttl=64 time=0.041 ms
64 bytes from 127.0.0.1: seq=2 ttl=64 time=0.058 ms
^C
--- localhost:5000 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 0.041/0.075/0.126 ms
$ 

• 最小run的图像以相同的方式失败：kubectl run coll-test --image=localhost:5000/collection:dev产生相同的事件：

Events:
  Type     Reason     Age               From               Message
  ----     ------     ----              ----               -------
  Normal   Scheduled  24s               default-scheduler  Successfully assigned dev/coll-test-cf4467b8d-8vpdk to minikube
  Normal   BackOff    23s               kubelet, minikube  Back-off pulling image "localhost:5000/collection:dev"
  Warning  Failed     23s               kubelet, minikube  Error: ImagePullBackOff
  Normal   Pulling    7s (x2 over 23s)  kubelet, minikube  Pulling image "localhost:5000/collection:dev"
  Warning  Failed     7s (x2 over 23s)  kubelet, minikube  Failed to pull image "localhost:5000/collection:dev": rpc error: code = Unknown desc = Error response from daemon: manifest for localhost:5000/collection:dev not found
  Warning  Failed     7s (x2 over 23s)  kubelet, minikube  Error: ErrImagePull

• 图像的条目存在于 repo 中：

$ curl http://localhost:5000/v2/_catalog
{"repositories":["collection","foo","bar"]}

部署和 Dockerfile

# deployment.yaml
apiVersion: apps/v1beta2
kind: Deployment
metadata:
  namespace: dev
  name: collection
  labels:
    app: collection
spec:
  replicas: 1
  selector:
    matchLabels:
      app: collection
  template:
    metadata:
      labels:
        app: collection
    spec:
      containers:
      - name: collection
        image: "localhost:5000/collection:dev"
        command: ["bash", "./collection_entry.sh"]
        imagePullPolicy: Always

# docker.collection
FROM python:3

WORKDIR /code
COPY . /code/
RUN adduser --system --group --no-create-home celery
RUN mkdir /var/run/celery
RUN mkdir /var/log/celery
RUN chown celery:celery /var/run/celery
RUN chown celery:celery /var/log/celery
RUN chmod 755 /var/run/celery
RUN chmod 755 /var/log/celery

RUN pip3 -q install -r requirements.txt
USER celery

ENTRYPOINT ./collection_entry.sh

Answer 1

1）你必须跑 eval $(minikube docker-env)

2) 使用 Minikube 的 Docker 守护进程构建镜像

docker build -t collection .

3) 像构建标签一样在 pod 规范中设置图像 - collection

4) 将 imagePullPolicy 设置为 Never，否则 Kubernetes 会尝试下载镜像。

apiVersion: apps/v1beta2
kind: Deployment
metadata:
  namespace: dev
  name: collection
  labels:
    app: collection
spec:
  replicas: 1
  selector:
    matchLabels:
      app: collection
  template:
    metadata:
      labels:
        app: collection
    spec:
      containers:
      - name: collection
        image: "collection"
        command: ["bash", "./collection_entry.sh"]
        imagePullPolicy: Never