Kubernetes helm chart notes

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

  • k8s/helm/examples

Helm - create own chart

1. kubectl create namespace <NS>

2. helm -n <NS> create <Name> <chart-name>

3. helm -n <Ns> list

4. helm -n <NS> uninstall <Name>

Helm 2022

• find charts @ https://artifacthub.io/packages/helm/

• e.g. jenkins

  helm repo add bitnami https://charts.bitnami.com/bitnami
  helm repo add https://artifacthub.io/packages/helm/jenkinsci/jenkins
  helm repo update
  helm search repo jenkins
  
  kubectl create namespace jenkins
  # namespace/jenkins created
  helm install jenkins jenkins/jenkins -n jenkins
  
  NOTES:
  1. Get your 'admin' user password by running:
    kubectl exec --namespace jenkins -it svc/jenkins -c jenkins -- /bin/cat /run/secrets/additional/chart-admin-password && echo
  2. Get the Jenkins URL to visit by running these commands in the same shell:
    echo http://127.0.0.1:8080
    kubectl --namespace jenkins port-forward svc/jenkins 8080:8080

Helm3 2020-04

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

   2. helm repo add stable https://kubernetes-charts.storage.googleapis.com/

   3. helm repo add
   4. helm search repo rabbitmq

Helm setup 2020-01

1. Create a dir and add Chart.yaml with version and maintainer.
2. Create requirements.yaml file with external charts needed

   • search for versions with $ helm search -l stable/rabbitmq-ha 

3. Install local charts from google with $  helm dependency update 

4. 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

1. Get k8s nodeResourceGroup grom gui or with

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

2. provision static ip with

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

3. 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