“Helm” is a package management tool for applications that run in the Kubernetes cluster.
https://helm.sh/docs/intro/using_helm/
Install Helm
https://helm.sh/docs/intro/install/
- You can install using the script.
curl -fsSL -o get_helm.sh https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3
chmod 700 get_helm.sh
./get_helm.sh
helm version
Concepts
Charts
- A Chart is a Helm package.
- It contains all the resource definitions necessary to run an application inside a Kubernetes cluster.
Repositories
- A Repository is a place where charts can be collected and shared.
- You can browse and download charts from the repository.
Releases
- A Release is an instance of a chart running in a Kubernetes cluster.
How to Use Helm
Artifact Hub Search
# search hub searches "https://artifacthub.io"
helm search hub wordpress
Local Repo Search
# add a local repo
helm repo add bitnami https://charts.bitnami.com/bitnami
helm repo add brigade https://brigadecore.github.io/charts
# update the repo
helm repo update
# check the local repo
helm repo list
# search the local repo
helm search repo wordpress
helm search repo nginx
Install Packages
It is a good idea to use a namespace to isolate the changes.
kubectl create ns wordpress
# helm install {release-name} {chart-name} {flags}
helm install my-wp bitnami/wordpress -n wordpress
# check the release
kubectl get all -n wordpress
It creates everything you need to run the WordPress website.
Check the status
helm list -n wordpress
helm status my-wp -n wordpress
A chart includes the following files:
- template yaml files
- values.yaml: configurable values
- Chart.yaml: the information about the chart
You can look at the chart files like this:
mkdir my-charts
cd my-charts
helm pull --untar bitnami/wordpress
cd wordpress
ls
ls templates
cat Chart.yaml
cat values.yaml
Clean up
It is easy to clean up all resources from the helm release.
helm uninstall my-wp -n wordpress
kubectl get all -n wordpress
Scriptorium 