Uploading personal docker image to Azure Container Registry - ErrImagePull - wordpress

Question

I am building a small docker image of this way:
In my Dockerfile I am adding an specific configuration in etc/apache2/apache2.conf about redirect http to https rule:
Specifically this rule
<VirtualHost *:80>
RewriteEngine On
RewriteCond %{HTTP:X-Forwarded-Proto} =http
RewriteRule .* https://%{HTTP:Host}%{REQUEST_URI} [L,R=permanent]
</VirtualHost>
So, my Dockerfile is
FROM wordpress:5.2.4
RUN apt-get update && apt-get install -y \
nano wget
COPY etc/apache2/apache2.conf /etc/apache2/apache2.conf
So, when it finish, I got two images in my local docker environment
REPOSITORY TAG
customize_wordpress 5.2.4
wordpress 5.2.4
Being customize_wordpress:5.2.4 my personal image and wordpress:5.2.4 the base public image that I used at FROM instruction above in the Dockerfile
Like my purpose is upload my custom image customize_wordpress:5.2.4 to azure container registry, I am following this article in order to do it
I am doing the docker tag command of this way
docker tag customize_wordpress:5.2.4 registryname.azurecr.io/customize_wordpress:5.2.4
And it works.
Also I push the image and it works as well
⟩ docker push registryname.azurecr.io/customize_wordpress:5.2.4
The push refers to repository [registryname.azurecr.io/customize_wordpress]
b63469233da6: Pushed
b032b61b15b2: Pushed
12fe3564ccac: Pushed
4e9b2aba858c: Pushed
b67d19e65ef6: Pushed
5.2.4: digest: sha256:dc62844f946a49f2e724fa38bad6e2cab73a4561b22b690876ab5534febd3569 size: 5128
[I]
So, I have these data as a environment variables in order to pass them to the helm command
export acr_login_server=registryname.azurecr.io
export acr_repository=customize_wordpress
export image_tag=5.2.4
But when I did the helm command
⟩ helm3 install wordpress-site-4 ./Deployments/Kubernetes/HelmCharts/wordpress/ --set image.registry=$acr_login_server,image.repository=$acr_repository,image.tag=$image_tag,image.pullPolicy=Always,wordpressUsername=$wordpressUsername,wordpressPassword=$wordpressPassword,wordpressEmail=$wordpressEmail,mariadb.enabled=false,externalDatabase.host=$database_host,externalDatabase.user=$database_user,externalDatabase.password=$database_password,externalDatabase.database=$database_name,externalDatabase.port=3306
I could see in my kubernetes environment that the pod say that the image is not pulled. I got
Error response from daemon: pull access denied for customize_wordpress, repository does not exist or may require 'docker login': denied: requested access to the resource is denied
Warning Failed 2m20s (x4 over 3m39s) kubelet, aks-defaultpool-34253081-vmss000001 Error: ErrImagePull
Normal Pulling 2m21s (x4 over 3m40s) kubelet, aks-defaultpool-34253081-vmss000001 Pulling image "customize_wordpress:5.2.4"
Warning Failed 2m20s (x4 over 3m39s) kubelet, aks-defaultpool-34253081-vmss000001 Failed to pull image "customize_wordpress:5.2.4": rpc error: code = Unknown desc = Error response from daemon: pull access denied for customize_wordpress, repository does not exist or may require 'docker login': denied: requested access to the resource is denied
Warning Failed 2m20s (x4 over 3m39s) kubelet, aks-defaultpool-34253081-vmss000001 Error: ErrImagePull
Normal BackOff 114s (x6 over 3m38s) kubelet, aks-defaultpool-34253081-vmss000001 Back-off pulling image "customize_wordpress:5.2.4"
Warning Failed 103s (x7 over 3m38s) kubelet, aks-defaultpool-34253081-vmss000001 Error: ImagePullBackOff
I am doing this helm command from azure devops, and previously I logged in to my ACR of multiple ways such as:
echo "Log in to an Azure Container Registry"
# docker login $(acr_login_server) --username $(service_principal_name_ci-cd-app-id) --password $(service_principal_name_ci-cd-password)
az acr login --name $(acr_name)
But the result is the same from the pod, I cannot pull the image
That's why I consider that I don't need to reference the docker registry secrets inside kubernetes and in the imagePullSecrets attribute in the helm chart values.yaml.
Despite everything I try to create that docker registry secret with my acr data but the result is the same as well.
How can I upload my customize image and pull it from Kubernetes?

Answer 1

Like my AKS cluster and my azure container registry, both already do exist before the private image installation, I didn't realize that I had to associate the aks cluster with the Azure container registry
It says here https://learn.microsoft.com/en-us/azure/aks/cluster-container-registry-integration#configure-acr-integration-for-existing-aks-clusters
So, this is the complete workflow to build our private docker image, uploaded to our private container registry (in my case Azure Container Registry) and pull that image from Azure Kubernetes service:
Build the image
docker build -t customize_wordpress:5.2.4 .
It creates the customize_wordpress:5.2.4 image
Creating tag: We need to create a tag in order to upload our image to our ACR
We have to include in the tag our ACR host server, in my case registryname.azurecr.io
Here for more information and here
⟩ docker tag customize_wordpress:5.2.4 registryname.azurecr.io/customize_wordpress:5.2.4
Push the image: Please, we have to be sure of use our complete tag created in the immediately previous step, I mean registryname.azurecr.io/customize_wordpress:5.2.4
⟩ docker push registryname.azurecr.io/customize_wordpress:5.2.4
The push refers to repository [registryname.azurecr.io/customize_wordpress]
b63469233da6: Pushed
b032b61b15b2: Pushed
b67d19e65ef6: Pushed
5.2.4: digest: sha256:dc62844f946a49f2e724fa38bad6e2cab73a4561b22b690876ab5534febd3569 size: 5128
And then before to install my Wordpress application, in my case from helm chart command (referenced above in my question), here comes the configuration of my ACR to work with my AKS cluster
I execute the aks update command:
⟩ az aks update -n MyClusterName -g MyResourceGroup --attach-acr MyACRName
So, when I install my helm chart, the image is up and running
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 14m default-scheduler Successfully assigned default/wordpress-site-4-6565b8c64f-w7xvq to aks-defaultpool-34253081-vmss000000
Normal Pulling 14m kubelet, aks-defaultpool-34253081-vmss000000 Pulling image "registryname.azurecr.io/customize_wordpress:5.2.4"
Normal Pulled 14m kubelet, aks-defaultpool-34253081-vmss000000 Successfully pulled image "registryname.azurecr.io/customize_wordpress:5.2.4"
Normal Created 14m kubelet, aks-defaultpool-34253081-vmss000000 Created container wordpress
If we do that, we don't need to reference the docker registry secret and any imagePullSecrets attribute in our helm chart or yaml file, our image will be pulled without reference any credentials