Helm is the k8s package management tools. like apt/yum in k8s, solve the service dependency in k8s.
K8s hook (Pod level)
- initContainer
- postStart
- preStop
Helm hook: (pod level)
- pre-install
- post-install
- pre-delete
- post-delete
- pre-upgrade
- post-upgrade
- pre-rollback
- post-rollback
create a template
helm create webserver
dry run a helm
helm install --name webserver --dry-run --debug webserver/
when one pod change in helm, use --set to change the value in Values file
helm upgrade webserver --set image.tag=1.7
check the deploy history
helm history webserver
REVISION UPDATE
1
2
3
check the history config revision=1
helm get webserver --revision 1
check the increment value change
helm get values webserver --revision 1
rollback
helm rollback webserver 1
helm is using k8s config map under kube-system to store the history.
list helm repo, check chartmuseum
helm repo list