docker - 在 k8s 中使用没有注册表设置的本地 docker 镜像

Question

我已经根据 official tutorial 设置了单节点 kubernetes .

除了官方文档，我还设置了单节点集群:

kubectl taint nodes --all node-role.kubernetes.io/master-

残疾人驱逐限制:

cat << EOF >> /var/lib/kubelet/config.yaml
evictionHard:
  imagefs.available: 1%
  memory.available: 100Mi
  nodefs.available: 1%
  nodefs.inodesFree: 1%
EOF

systemctl daemon-reload
systemctl restart kubelet

并为 Docker 设置 systemd 驱动程序:

cat << EOF > /etc/docker/daemon.json
{
  "exec-opts": ["native.cgroupdriver=systemd"],
  "log-driver": "json-file",
  "log-opts": {
    "max-size": "100m"
  },
  "storage-driver": "overlay2"
}
EOF

systemctl daemon-reload
systemctl restart docker

我试过以下:

docker build -t localhost:5000/my-image .
kubectl run -it --rm --restart=Always --image=localhost:5000/my-image my-image

但在 pod 日志中我看到 ImagePullBackOff .如果我设置了本地存储库并且我做了 docker push localhost:5000/my-image在我构建图像后，一切正常。

是否可以使用本地镜像(在发布 docker images 后已经可用)而无需设置本地存储库，推送到该存储库然后从中拉取？

Answer 1

您只需要设置 imagePullPolicy在您的 Pod container 中的模板规范到 Never .否则 kubelet 将尝试拉图像。示例 Pod定义可能如下所示:

apiVersion: v1
kind: Pod
metadata:
  name: test
spec:
  containers:
    - name: uses-local-image
      image: local-image-name
      imagePullPolicy: Never

更多相关信息，您可以找到 here .

By default, the kubelet will try to pull each image from the specified registry. However, if the imagePullPolicy property of the container is set to IfNotPresent or Never, then a local image is used (preferentially or exclusively, respectively).

If you want to rely on pre-pulled images as a substitute for registry authentication, you must ensure all nodes in the cluster have the same pre-pulled images.

This can be used to preload certain images for speed or as an alternative to authenticating to a private registry.

All pods will have read access to any pre-pulled images.