Helm Concepts

Internal

• Helm

Chart

Helm Glossary - Chart

A chart is a Helm package, the Kubernetes equivalent of a yum RPM file or a Homebrew formula. A chart contains all resource definitions necessary to deploy and run an application inside Kubernetes.

Charts are installed and turned into releases with helm install.

Chart Operations

• helm install
• helm inspect

Release

Helm Glossary - Release

A release is a running instantiation of a chart, to which a specific config was applied. Whenever a chart is installed, a new release is created. One chart can be installed multiple times into the same cluster, and each can be independently managed and upgraded. Each release has its own release name.

Release Operations

• helm list
• helm status
• helm delete

Repository

Helm Glossary - Repository

A repository is a place where charts are collected and shared. When Helm is installed, it is pre-configured to look into the official Kubernetes chart repository, named "stable". Repositories can be searched for charts with helm search.

Repository Operations

• helm repo
• helm search

Dependency

• If I rely on a dependency referred from an external Helm repository, and the repository exposes newer versions, can I still rely on the fact that the old version is still available? I might not want to upgrade to the "latest", but keep using a version I tested with and was proven stable.

Runtime

The Helm Client

The client is responsible for managing charts.

The Tiller Server

The server is responsible for managing releases.

Tiller stores release information in ConfigMaps in the namespace where it is running. It could be configured to use a storage backend that uses Secrets for storing release information. More here. It could also be configured to use an SQL storage backend for storing release information. More here.

Security

Security Concepts