dockerkubernetesdocker-registry

Why am I getting an ErrImagePull error in this Kubernetes deployment?


I'm trying to create a local Kubernetes deployment using Minikube, Docker Registry, and a demo node project.

The first thing I did was install Docker v1.12.3, then Minikube v0.12.2.

Then I created a Docker Registry container by running this command (via this tutorial, only running the first command below)

docker run -d -p 5000:5000 --name registry registry:2

Next I ran this minikube command to create a local kubernetes cluster:

minikube start --vm-driver="virtualbox" --insecure-registry="0.0.0.0:5000"

My project structure looks like this:

.
├── Dockerfile
└── server.js

and my Dockerfile looks like this:

FROM node:7.1.0
EXPOSE 8080
COPY server.js .
CMD node server.js

Then I built my own docker image and pushed it to my private repository:

docker build -t hello-node .
docker tag hello-node localhost:5000/hello-node
docker push localhost:5000/hello-node

Then I tried to run a deployment with this command:

kubectl run hello-node --image=localhost:5000/hello-node --port=8888

But then I get this:

sudo kubectl get pods --all-namespaces                                                                                                                             
NAMESPACE     NAME                          READY     STATUS         RESTARTS   AGE
default       hello-node-3745105022-gzs5a   0/1       ErrImagePull   0          11m
kube-system   kube-addon-manager-minikube   1/1       Running        4          10d
kube-system   kube-dns-v20-2x64k            3/3       Running        12         10d
kube-system   kubernetes-dashboard-mjpjv    1/1       Running        4          10d

I think I might be missing some kind of docker registry authentication, but as I'm googling I can't find something that I understand. Could someone please point me in the right direction?

Edit

After using ssh to access bash on the kubernetes VM and pull the hello-node image from my private registry by using this command:

minikube ssh
Boot2Docker version 1.11.1, build master : 901340f - Fri Jul  1 
22:52:19 UTC 2016
Docker version 1.11.1, build 5604cbe
docker@minikube:~$ sudo docker pull localhost:5000/hello-node
Using default tag: latest
Pulling repository localhost:5000/hello-node
Error while pulling image: Get http://localhost:5000/v1/repositories/hello-node/images: dial tcp 127.0.0.1:5000: getsockopt: connection refused

Is localhost:5000 the correct address to use within the kubernetes host VM?


Solution

  • It looks like you're running the registry on the host. In fact, you need to run the registry inside the VM. You can point your docker client to the docker daemon inside the minikube VM by running this command first eval $(minikube docker-env) in your shell.

    Then, you can run the docker build command on your host, but it will build inside the VM.

    In fact, if your goal is to simply run the local version of your images, you should run the eval $(minikube docker-env) to point towards the docker daemon in your VM, and set the imagePullPolicy: IfNotPresent in your pod YAML. Then, kubernetes will use a locally built image if available.