Everything You Need to Know to Start Using Helm
Default Helm Labels
In our previous example, we ran the following command to verify the installation:
kubectl get all -l app.kubernetes.io/instance=my-wordpress
The label app.kubernetes.io/instance is one of the default labels that Helm adds to all the Kubernetes resources it creates. This label helps identify which resources belong to a specific Helm release.
There are other default labels automatically added by Helm as well:
app.kubernetes.io/name: The name of the chart (e.g.,wordpress).app.kubernetes.io/version: The version of the application (e.g.,5.8.1).app.kubernetes.io/managed-by: The tool managing the deployment (e.g.,Helm).app.kubernetes.io/component: The component within the application (e.g.,web,database,frontend,backendetc., depending on the chart).app.kubernetes.io/part-of: The name of the larger application this component is part of (e.g.,my-application).helm.sh/chart: The name and version of the chart (e.g.,wordpress-10.1.5).
These labels are created based on the information provided in the Chart.yaml file and the release name specified during installation. The following table summarizes what's created and how:
| Label | Required/Optional | Description | How it's Set |
|---|---|---|---|
| app.kubernetes.io/name | Required | Logical name of the application. Groups all components belonging to a single app. | Usually set using {{ template "name" . }}, which typically resolves to .Chart.Name. |
| helm.sh/chart | Required | Identifies which chart and chart version produced this resource. Useful for auditing and debugging. | Helm sets this via {{ .Chart.Name }}-{{ .Chart.Version \| replace "+" "_" }} so labels remain valid. |
| app.kubernetes.io/managed-by | Required | Indicates the management tool (always Helm for Helm-managed objects). | Automatically set to {{ .Release.Service }}, which equals "Helm". |
| app.kubernetes.io/instance | Required | Distinguishes different deployments of the same chart (prod, staging, test, etc.). | Set to {{ .Release.Name }}, the name passed during helm install/upgrade. |
| app.kubernetes.io/version | Optional | Version of the underlying application (e.g., WordPress, Redis), not the chart version. | Usually set using {{ .Chart.AppVersion }} from Chart.yaml. |
| app.kubernetes.io/component | Optional | Identifies the component role: frontend, backend, database, worker, etc. | Manually defined in chart templates or values.yaml. |
| app.kubernetes.io/part-of | Optional | Groups multiple charts/components under one larger system or “application”. | Manually set by chart authors using a fixed value or {{ .Values.appName }}. |
Below is a practical explanation of every template reference that appears in the table:
{{ template "name" . }}
This calls a named template defined in _helpers.tpl files. Many charts include a template like this:
{{- define "name" -}}
{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" -}}
{{- end -}}
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