Deploying a Helm chart from your private registry in Kubernetes

Last updated 14 April, 2022.

OVHcloud Managed Private Registry service is a composite cloud-native registry which supports both container image management and Helm chart management.

This guide will explain how to deploy a Helm chart from your OVHcloud Managed Private Registry in a Kubernetes cluster.

Before you begin

This tutorial presupposes that you already have a working OVHcloud Managed Kubernetes cluster, and some basic knowledge of how to operate it. If you want to know more on those topics, please look at the deploying a Hello World application documentation. You will need to have Helm installed on your cluster (see the installing helm guide for more information).

You also need to have a working OVHcloud Managed Private Registry and have followed the guide on managing Helm charts in the OVHcloud Managed Private Registry.

You should have at least one wordpress Helm chart in your Private Registry:

Prerequisites

We (the OVHcloud Managed Kubernetes Service team) are working on a patch to be released in early 2022. In the meantime, please remove the default storage class and install the new one.

• Delete the concerned StorageClass that you are using by default

kubectl delete storageclasses.storage.k8s.io csi-cinder-high-speed

It will delete the existing StorageClass:

$ kubectl delete storageclasses.storage.k8s.io csi-cinder-high-speed
storageclass.storage.k8s.io "csi-cinder-high-speed" deleted

• Create a new StorageClass with the required fix

kubectl apply -f https://raw.githubusercontent.com/ovh/docs/develop/pages/platform/kubernetes-k8s/fix-persistent-volumes-permissions/files/fixed-cinder-high-speed-storage-class.yaml

It will apply the correct StorageClass YAML manifest:

$ kubectl apply -f https://raw.githubusercontent.com/ovh/docs/develop/pages/platform/kubernetes-k8s/fix-persistent-volumes-permissions/files/fixed-cinder-high-speed-storage-class.yaml
storageclass.storage.k8s.io/csi-cinder-high-speed created

If you have already installed a previous version of Bitnami's WordPress Helm chart, please follow the following step by step guide.

• Delete the concerned Helm Chart

For example with the Helm Chart wordpress which is concerned by this behavior:

helm uninstall wordpress

And don't forget to verify if concerned PersistentVolumeClaim (PVC) and PersistentVolume (PV) have been deleted before reinstalling the Helm Chart:

kubectl get persistentvolumeclaims -A | grep wordpress
kubectl get persistentvolumes 

If a PersistentVolumeClaim is listed, please delete it (the PersistentVolume will be deleted automatically).

kubectl delete pvc data-my-first-k8s-wordpress-mariadb-0

The command will delete the remaining PersistentVolumeClaim:

$ kubectl delete pvc data-my-first-k8s-wordpress-mariadb-0
persistentvolumeclaim "data-my-first-k8s-wordpress-mariadb-0" deleted

Instructions

Deploying a chart from your registry in Kubernetes

In this step you are going to deploy a chart from your OVHcloud Managed Private Registry into an OVHcloud Managed Kubernetes cluster (or any other Kubernetes cluster).

As indicated in the Before you begin section, you need to have helm installed in your cluster and a working helm CLI in your workstation (see the installing Helm guide for more information if needed).

Run the command helm version to make sure the helm CLI is correctly installed locally.

$ helm version
version.BuildInfo{Version:"v3.7.0", GitCommit:"eeac83883cb4014fe60267ec6373570374ce770b", GitTreeState:"clean", GoVersion:"go1.17"}

Add your OVHcloud Managed Private Registry to the repository list

The first thing to do is add your OVHcloud Managed Private Registry to the Helm's repository list, with helm repo add command.

You can do it in two ways: adding your private registry as single index entry point or adding each project as a separate index entry point.

• Adding your OVHcloud Managed Private Registry as a unified single index entry point

In this mode, Helm will be able to use all the charts in any of your projects which are accessible by the currently authenticated user.

helm repo add --username <username> --password <password> <repo name> https://<repo url>/chartrepo

• Adding a project in your OVHcloud Managed Private Registry as a separate index entry point

In this mode, Helm only can pull charts from the specified project.

helm repo add --username <username> --password <password> <repo name> https://<repo url>/chartrepo/<project>

In my example, I added the project in the private registry as a separate index entry point:

$ helm repo add --username private-user --password xxxxxx privreg https://ab1cd23e.gra7.container-registry.ovh.net/chartrepo/private
"privreg" has been added to your repositories

Install charts

Before installing, make sure your the chart index is synchronized with the helm repo update command.

In my case:

$ helm repo update
Hang tight while we grab the latest from your chart repositories...
...Successfully got an update from the "gpu-helm-charts" chart repository
...
...Successfully got an update from the "privreg" chart repository
...
Update Complete. ⎈Happy Helming!⎈

Look for your chart:

helm search repo wordpress

In my case, it finds several versions of WordPress chart, the official ones in the bitnami Helm repository, and the one in my privreg private registry project:

$ helm search repo wordpress
NAME                    CHART VERSION   APP VERSION DESCRIPTION
bitnami/wordpress       13.2.1          5.9.3       WordPress is the world's most popular blogging ...
bitnami/wordpress-intel 0.2.0           5.9.3       WordPress for Intel is the most popular bloggin...
privreg/wordpress       13.1.4          5.9.2       WordPress is the world's most popular blogging ...

Everything is ready, so now you can install the chart into your Kubernetes:

helm install wordpress --username <username> --password <password> privreg/wordpress

In my case:

$ helm install wordpress --username private-user --password xxxxxx privreg/wordpress
NAME: wordpress
LAST DEPLOYED: Thu Apr 14 09:33:33 2022
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
CHART NAME: wordpress
CHART VERSION: 13.1.4
APP VERSION: 5.9.2

** Please be patient while the chart is being deployed **

Your WordPress site can be accessed through the following DNS name from within your cluster:

    wordpress.default.svc.cluster.local (port 80)

To access your WordPress site from outside the cluster follow the steps below:

1. Get the WordPress URL by running these commands:

  NOTE: It may take a few minutes for the LoadBalancer IP to be available.
        Watch the status with: 'kubectl get svc --namespace default -w wordpress'

   export SERVICE_IP=$(kubectl get svc --namespace default wordpress --include "{{ range (index .status.loadBalancer.ingress 0) }}{{ . }}{{ end }}")
   echo "WordPress URL: http://$SERVICE_IP/"
   echo "WordPress Admin URL: http://$SERVICE_IP/admin"

2. Open a browser and access WordPress using the obtained URL.

3. Login with the following credentials below to see your blog:

  echo Username: user
  echo Password: $(kubectl get secret --namespace default wordpress -o jsonpath="{.data.wordpress-password}" | base64 --decode)

Check your WordPress is running correctly:

$ kubectl get pod -l app.kubernetes.io/instance=wordpress
NAME                         READY   STATUS    RESTARTS   AGE
wordpress-8586785c5d-cttz4   1/1     Running   0          85s
wordpress-mariadb-0          1/1     Running   0          85s

Go further

To have an overview of the OVHcloud Managed Private Registry service, you can go to the OVHcloud Managed Private Registry site.

Join our community of users on https://community.ovh.com/en/.

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