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I was following this URL: How to use local docker images with Minikube? I couldn't add a comment, so thought of putting my question here:

On my laptop, I have Linux Mint OS. Details as below:

Mint version 19, 
Code name : Tara,
PackageBase : Ubuntu Bionic
Cinnamon (64-bit)

As per one the answer on the above-referenced link:

  1. I started minikube and checked pods and deployments
xxxxxxxxx:~$ pwd
/home/sj

xxxxxxxxxx:~$ minikube start
xxxxxxxxxx:~$ kubectl get pods
xxxxxxxxxx:~$ kubectl get deployments

I ran command docker images

xxxxxxxxx:~$ docker images

REPOSITORY                        TAG                 IMAGE ID            CREATED             SIZE
<username>/spring-docker-01   latest              e10f88e1308d        6 days ago          640MB
openjdk                           8                   81f83aac57d6        4 weeks ago         624MB
mysql                             5.7                 563a026a1511        4 weeks ago         372MB
  1. I ran below command:

eval $(minikube docker-env)

  1. Now when I check docker images, looks like as the README describes, it reuses the Docker daemon from Minikube with eval $(minikube docker-env).

    xxxxxxxxxxxxx:~$ docker images

REPOSITORY                                 TAG                 IMAGE ID            CREATED             SIZE
nginx                                      alpine              33c5c6e11024        9 days ago          17.7MB
k8s.gcr.io/coredns                         1.2.2               367cdc8433a4        5 weeks ago         39.2MB
k8s.gcr.io/kubernetes-dashboard-amd64      v1.10.0             0dab2435c100        5 weeks ago         122MB
k8s.gcr.io/kube-proxy-amd64                v1.10.0             bfc21aadc7d3        6 months ago        97MB
k8s.gcr.io/kube-controller-manager-amd64   v1.10.0             ad86dbed1555        6 months ago        148MB
k8s.gcr.io/kube-apiserver-amd64            v1.10.0             af20925d51a3        6 months ago        225MB
k8s.gcr.io/kube-scheduler-amd64            v1.10.0             704ba848e69a        6 months ago        50.4MB
k8s.gcr.io/etcd-amd64                      3.1.12              52920ad46f5b        6 months ago        193MB
k8s.gcr.io/kube-addon-manager              v8.6                9c16409588eb        7 months ago        78.4MB
k8s.gcr.io/k8s-dns-dnsmasq-nanny-amd64     1.14.8              c2ce1ffb51ed        9 months ago        41MB
k8s.gcr.io/k8s-dns-sidecar-amd64           1.14.8              6f7f2dc7fab5        9 months ago        42.2MB
k8s.gcr.io/k8s-dns-kube-dns-amd64          1.14.8              80cc5ea4b547        9 months ago        50.5MB
k8s.gcr.io/pause-amd64                     3.1                 da86e6ba6ca1        9 months ago        742kB
gcr.io/k8s-minikube/storage-provisioner    v1.8.1              4689081edb10        11 months ago       80.8MB
k8s.gcr.io/echoserver                      1.4                 a90209bb39e3        2 years ago         140MB

Note: if noticed docker images command pulled different images before and after step 2.

  1. As I didn't see the image that I wanted to put on minikube, I pulled it from my docker hub.
xxxxxxxxxxxxx:~$ docker pull <username>/spring-docker-01
Using default tag: latest
latest: Pulling from <username>/spring-docker-01
05d1a5232b46: Pull complete 
5cee356eda6b: Pull complete 
89d3385f0fd3: Pull complete 
80ae6b477848: Pull complete 
40624ba8b77e: Pull complete 
8081dc39373d: Pull complete 
8a4b3841871b: Pull complete 
b919b8fd1620: Pull complete 
2760538fe600: Pull complete 
48e4bd518143: Pull complete 
Digest: sha256:277e8f7cfffdfe782df86eb0cd0663823efc3f17bb5d4c164a149e6a59865e11
Status: Downloaded newer image for <username>/spring-docker-01:latest
  1. Verified if I can see that image using "docker images" command.
xxxxxxxxxxxxx:~$ docker images
REPOSITORY                                 TAG                 IMAGE ID            CREATED             SIZE
<username>/spring-docker-01            latest              e10f88e1308d        6 days ago          640MB
nginx                                      alpine              33c5c6e11024        10 days ago         17.7MB
  1. Then I tried to build image as stated in referenced link step.
xxxxxxxxxx:~$ docker build -t <username>/spring-docker-01 .
unable to prepare context: unable to evaluate symlinks in Dockerfile path: lstat /home/sj/Dockerfile: no such file or directory

As the error states that dockerfile doesn't exist at the location, I am not sure where exactly I can see dockerfile for the image I had pulled from docker hub.

Looks like I have to go to the location where the image has been pulled and from that location, I need to run the above-mentioned command. Please correct me wrong.

Below are the steps, I will be doing after I fix the above-mentioned issue.

# Run in minikube
kubectl run hello-foo --image=myImage --image-pull-policy=Never

# Check that it's running
kubectl get pods

UPDATE-1

There is mistake in above steps. Step 6 is not needed. Image has already been pulled from docker hub, so no need of docker build command.

With that, I went ahead and followed instructions as mentioned by @aurelius in response.

xxxxxxxxx:~$ kubectl run sdk-02 --image=<username>/spring-docker-01:latest --image-pull-policy=Never
kubectl run --generator=deployment/apps.v1beta1 is DEPRECATED and will be removed in a future version. Use kubectl create instead.
deployment.apps/sdk-02 created

Checked pods and deployments

xxxxxxxxx:~$ kubectl get pods
NAME                         READY   STATUS    RESTARTS   AGE
sdk-02-b6db97984-2znlt       1/1     Running   0          27s
xxxxxxxxx:~$ kubectl get deployments
NAME        DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
sdk-02      1         1         1            1           35s

Then exposed deployment on port 8084 as I was using other ports like 8080 thru 8083

xxxxxxxxx:~$ kubectl expose deployment sdk-02 --type=NodePort --port=8084
service/sdk-02 exposed

Then verified if service has been started, checked if no issue on kubernetes dashboard and then checked the url

xxxxxxxxx:~$ kubectl get services
NAME         TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
kubernetes   ClusterIP      10.96.0.1        <none>        443/TCP          7h
sdk-02       NodePort       10.100.125.120   <none>        8084:30362/TCP   13s

xxxxxxxxx:~$ minikube service sdk-02 --url
http://192.168.99.101:30362

When I tried to open URL: http://192.168.99.101:30362 in browser I got message:

This site can’t be reached
192.168.99.101 refused to connect.
Search Google for 192 168 101 30362
ERR_CONNECTION_REFUSED

So the question : Is there any issue with steps performed?

UPDATE-2

The issue was with below step:

xxxxxxxxx:~$ kubectl expose deployment sdk-02 --type=NodePort --port=8084
    service/sdk-02 exposed

Upon checking Dockerfile of my image : <username>/spring-docker-01:latest I was exposing it to 8083 something like EXPOSE 8083 May be that was causing issue. So I went ahead and changed expose command:

xxxxxxxxx:~$ kubectl expose deployment sdk-02 --type=NodePort --port=8083
service/sdk-02 exposed

And then it started working.

If anyone has something to add to this, please feel free.

However I am still not sure where exactly I can see dockerfile for the image I had pulled from docker hub.

Shivraj
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  • You should run the command `docker build -t shivnilesh1109/spring-docker-01 .` in the directory which the Dockerfile in. – Charles Xu Oct 05 '18 at 03:57
  • @CharlesXu-MSFT That's what my question was. Let me rephrase it : I have pulled a image "myImage" from my docker hub using command `docker pull username/myImage` . How to find out location where that image is stored on my location machine? – Shivraj Oct 05 '18 at 23:17
  • I have updated description with more details **UPDATE-1** Please have a look at all steps carefully and let me know if I am making any mistake there. – Shivraj Oct 07 '18 at 04:33
  • Got this working. However only 1 question remains. Please check **UPDATE-2** – Shivraj Oct 08 '18 at 01:49

5 Answers5

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The docker build does not know what you mean by your command, because flag -t requires specific format:

--tag , -t Name and optionally a tag in the ‘name:tag’ format

xxxxxxxxxx:~/Downloads$ docker build -t shivnilesh1109/spring-docker-01 .

So the proper command here should be:

docker build -t shivnilesh1109/spring-docker-01:v1(1) .(2)

(1) desired name of your container:tag (2) directory in which your dockerfile is.

After you proceed to minikube deployment, it will be enough just to run: kubectl run *desired name of deployment/pod* --image=*name of the container with tag* --image-pull-policy=Never

If this would not fix your issue, try adding the path to Dockerfile manually. I've tested this on my machine and error stopped after using proper tagging of the image and tested this also with full path to Dockerfile otherwise I had the same error as you.

aurelius
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  • I have problem with (2) from your response. Let me rephrase it : I have pulled a image "myImage" from my docker hub using command `docker pull username/myImage` . How to find out location where that image is stored on my location machine? – Shivraj Oct 05 '18 at 23:21
  • I have updated description with more details **UPDATE-1** Please have a look at all steps carefully and let me know if I am making any mistake there. – Shivraj Oct 07 '18 at 04:34
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For you UPDATE-2 question, also to help you to understand the port exposed in the Dockerfile and in the command kubectl expose.

Dockerfile:

The EXPOSE instruction does not actually publish the port. It functions as a type of documentation between the person who builds the image and the person who runs the container, about which ports are intended to be published.

For more details, see EXPOSE.

Kubectl expose:

--port: The port that the service should serve on. Copied from the resource being exposed, if unspecified

--target-port: Name or number for the port on the container that the service should direct traffic to. Optional.

For more details, see kubectl expose.

So I think you should add the parameters --target-port with the port that you exposed in the Dockerfile. And then the port mapping will be correct.

Charles Xu
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  • _Dokerfile_ has `EXPOSE 8083` then _kubectl expose_ I changed command with `--port 8084 --target-port 8083` and it worked. Thanks for answer. – Shivraj Oct 09 '18 at 03:04
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You can just create a Dockerfile with this content:

FROM shivnilesh1109/spring-docker-01

Then run:

docker build -t my-spring-docker-01 .
Rico
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  • command `FROM shivnilesh1109/spring-docker-01` didn't work. Not sure if I understood your response correctly. – Shivraj Oct 05 '18 at 23:20
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    That's not a command. You need to create a file named `Dockerfile` and inside that file you need to add `FROM shivnilesh1109/spring-docker-01` – Rico Oct 05 '18 at 23:22
  • The basic problem what I am facing still remains the same. I have pulled a image "myImage" from my docker hub using command `docker pull username/myImage` . In order to create dockerfile, first I need to find out location where that image is stored on my location machine. I am having problem with that. – Shivraj Oct 05 '18 at 23:36
  • I even tried to go to docker root directory: `xxxxxxxxxx:/var/lib/docker# ls **builder buildkit containerd containers image network overlay2 plugins runtimes swarm tmp trust volumes**` Not sure where exactly that pulled image gets stored. – Shivraj Oct 05 '18 at 23:38
  • What are you trying to do? Why do you need the files on your local docker image? – Rico Oct 06 '18 at 00:10
  • I am confused now with that question of yours. All I am trying to do is use one of the local image with minikube. I am trying exact same steps as mentioned in the issue description. Am I doing some mistake in any of those steps? – Shivraj Oct 06 '18 at 00:50
  • Got this working. However only 1 question remains. Please check **UPDATE-2** – Shivraj Oct 08 '18 at 01:50
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try adding your local docker image to minikube's cache , like so :

minikube cache add docker-image-name:latesttag

then set imagePullPolicy:Never in the yaml file.

Alferd Nobel
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Check if Dockerfile is listed in .dockerignore, if so - comment it out

Valentin Kantor
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