Kubernetes helm chart notes

Links: k8s/Azure , k8s/Monitoring , k8s/helm/HelmV2ToV3 , https://lzone.de/blog/Helm-Best-Practices

Helm3 2020-04

On local chart (main deployment of all components)
1. helm repo index .
  - This index's charts under ./charts and create a new ./index.yam

Helm setup 2020-01

Create a dir and add Chart.yaml with version and maintainer.
Create requirements.yaml file with external charts needed
- search for versions with $ helm search -l stable/rabbitmq-ha
Install local charts from google with $ helm dependency update
Verify with $ helm dependency list

Install 2019-03

Ran official curl, and get_helm, all fine
When deploying chart got an error, tiller not allowed to create namespaces.

Fixed with command belown and helm init --upgrade

kubectl create serviceaccount --namespace kube-system tiller
 # serviceaccount "tiller" created

kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller
 # clusterrolebinding "tiller-cluster-rule" created

kubectl patch deploy --namespace kube-system tiller-deploy -p '{"spec":{"template":{"spec":{"serviceAccount":"tiller"}}}}' 
 # deployment "tiller-deploy" patched

201903 add ingress and static ip

Get k8s nodeResourceGroup grom gui or with

az aks show --resource-group <rgK8S> --name <clusterName> --query nodeResourceGroup -o tsv

provision static ip with

az network public-ip create --resource-group <MC_K8S_from_above> --name <cluster-PublicIP> --allocation-method static

assign ip to nginx ingress controller

helm install stable/nginx-ingress  -namespace kube-system  --set controller.service.loadBalancerIP="52.23.23.32"  --set controller.replicaCount=2

Run 2019-02

helm install --name p1 git/helmchart/ --namespace piet --set "env=DEV" --timeout 600
Run: helm ls --all p1; to check the status of the release
run: helm del --purge p1; to delete it
helm status p1
helm history p1
helm rollback p1 3; roll back to version 3
helm rollback; to last successfully DEPLOYED revision
helm upgrade --debug --dry-run
helm upgrade --install

Tricks

Use checksum of config map to change app annotation and force a new version to be deployed for apps that do not pick up new configs.
- https://helm.sh/docs/developing_charts/#hooks
- https://youtu.be/WugC_mbbiWU?t=1043
hooks
```
annotation:
  "helm.sh/hook": " "
```

HELM install/uninstall

Please look for official current documentation

helmins() {
 kubectl -n kube-system create serviceaccount tiller
 kubectl create clusterrolebinding tiller --clusterrole cluster-admin --serviceaccount=kube-system:tiller
 helm init --service-account=tiller
}
helmdel() {
 kubectl -n kube-system delete deployment tiller-deploy
 kubectl delete clusterrolebinding tiller
 kubectl -n kube-system delete serviceaccount tiller
 
}

CategoryK8sKubernetes