Use local docker image with minikube - docker

Question

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:
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
I ran below command:
eval $(minikube docker-env)
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.
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
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
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.

Answer 1

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.

Answer 2

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.

Answer 3

You can just create a Dockerfile with this content:
FROM shivnilesh1109/spring-docker-01
Then run:
docker build -t my-spring-docker-01 .

Answer 4

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.