Helm Charts and Apps

In this section, you’ll learn how to manage Helm chart repositories and apps in Rancher.

How Helm Charts Work in Rancher

Helm chart repositories in Rancher are managed using Apps.

Rancher uses a catalog-like system to import bundles of charts from repositories and then uses those charts to either deploy custom Kubernetes applications or Rancher’s tools such as Monitoring or Istio. Rancher tools come as pre-loaded repositories which deploy as standalone Helm charts. Any additional repositories are only added to the current cluster.

Catalogs, Apps, and the Rancher UI

xref:[Rancher v2.4 and earlier], repositories of ready-to-deploy applications were called "catalogs". These repositories were managed through the Catalogs section of the UI.

Rancher v2.5 replaced the former catalog system with a new Apps & Marketplace feature.

Since Rancher v2.6.5, the Apps & Marketplace feature is named Apps in the UI.

Versioning Scheme

The Rancher feature charts versioning scheme is centered around the major version of the charts and the +up annotation for upstream charts, where applicable.

Major Version: The major versions of feature charts are tied to particular minor versions of Rancher. When you upgrade to a new Rancher minor version, you should ensure that all of your feature charts are also upgraded to the correct release line for the chart.

Charts based on upstream: When you upgrade, make sure that the upstream chart version is compatible with your Rancher version. The +up annotation for the chart indicates which upstream version the Rancher chart is tracking. For example, 100.x.x+up16.6.0 for Monitoring tracks upstream kube-prometheus-stack 16.6.0 with some additional Rancher patches.

When upgrading Rancher versions, don’t downgrade the version of the chart that you are using. For example, if you are using a version of Monitoring that is later than 16.6.0 in Rancher v2.5, you shouldn’t upgrade to 100.x.x+up16.6.0. Instead, you should upgrade to the appropriate version in the next release.

Prerelease Versions

Prereleases adhere to the specification defined by Semantic Versioning 2.0.0. For example, a Helm chart with a version of 0.1.3-dev.12ab4f is considered a prerelease. Prerelease versions are not displayed by default and must be configured to do so.

To display prerelease versions:

  1. Click on your user avatar in the upper right corner.

  2. Click Preferences.

  3. Under Helm Charts, select Include Prerelease Versions.

Feature Charts

Name Supported Minimum Version Supported Maximum Version

external-ip-webhook

100.0.0+up1.0.0

100.0.1+up1.0.1

harvester-cloud-provider

100.0.2+up0.1.12

100.0.2+up0.1.12

harvester-csi-driver

100.0.2+up0.1.11

100.0.2+up0.1.11

neuvector

100.0.0+up2.2.0

100.0.0+up2.2.0

rancher-alerting-drivers

100.0.0

100.0.2

rancher-backup

2.0.1

2.1.2

rancher-cis-benchmark

2.0.1

2.0.4

rancher-gatekeeper

100.0.0+up3.6.0

100.1.0+up3.7.1

rancher-istio

100.0.0+up1.10.4

100.3.0+up1.13.3

rancher-logging

100.0.0+up3.12.0

100.1.2+up3.17.4

rancher-longhorn

100.0.0+up1.1.2

100.1.2+up1.2.4

rancher-monitoring

100.0.0+up16.6.0

100.1.2+up19.0.3

rancher-sriov (experimental)

100.0.0+up0.1.0

100.0.3+up0.1.0

rancher-vsphere-cpi

100.3.0+up1.2.1

100.3.0+up1.2.1

rancher-vsphere-csi

100.3.0+up2.5.1-rancher1

100.3.0+up2.5.1-rancher1

rancher-wins-upgrader

0.0.100

100.0.1+up0.0.1

Access Charts

The Charts page contains all Rancher, Partner, and Custom charts. You can filter charts by selecting the left-most dropdown menu:

  • Rancher tools such as Logging or Monitoring are listed under the Rancher label.

  • Partner charts are under the Partners label.

  • Custom charts are listed under the name of their respective repository.

All three types of charts are deployed and managed in the same way.

Apps managed by the Cluster Manager (the global view in the legacy Rancher UI) continue to be managed only by the Cluster Manager, and apps managed with Apps in the new UI must be managed only by Apps.

To access the Charts page:

  1. Click ☰ > Cluster Management.

  2. Find the name of the cluster whose charts you want to access. Click Explore at the end of the cluster’s row.

  3. In the left navigation menu on the Cluster Dashboard, click Apps  Charts.

Manage Repositories

The Repositories page lists your Helm repositories. These include traditional Helm endpoints which have an index.yaml, and Git repositories that are cloned and point to a specific branch. To use custom charts, add your repository here. After you add a repository, you can access custom charts in the Charts page, listed under the name of the repository.

To access the Repositories page:

  1. Click ☰ > Cluster Management.

  2. Find the name of the cluster whose repositories you want to access. Click Explore at the end of the cluster’s row.

  3. In the left navigation menu on the Cluster Dashboard, click Apps  Repositories.

Add Custom Git Repositories

To add a custom Git repository that contains your Helm charts or cluster template definitions:

  1. Click ☰ > Cluster Management.

  2. Find the name of the cluster whose repositories you want to access. Click Explore at the end of the cluster’s row.

  3. In the left navigation menu on the Cluster Dashboard, click Apps  Repositories.

  4. Click Create.

  5. Select the target, Git repository containing Helm chart…​.

  6. You must enter a name and a Git repository URL. The other fields, including the description, are optional. Enter an alternative branch name if you don’t want to pull from whichever branch the repo owner has set as the default. Usually, the default branch is named either main or master.

  7. Click Create to add the repository.

After you add a chart repository to Rancher, it becomes available immediately.

Add Custom Helm Chart Repositories

You can add your own Helm chart repositories to serve chart packages to Rancher. You can use any HTTP server, as long as the server can respond to GET requests and serve YAML files and tar archives.

For more information on Helm chart repositories, see the official Helm docs.

To add a custom Helm chart repository to Rancher:

  1. Click ☰. Under Explore Cluster in the left navigation menu, select a cluster.

  2. In the left navigation menu on the Cluster Dashboard, click Apps  Charts.

  3. Click Create.

  4. Select the target, http(s) URL to an index generated by Helm.

  5. Enter a repo name and the index URL address of the chart repository.

  6. Click Create to add the repository.

Add Private Git/Helm Chart Repositories

You can add private Git or Helm chart repositories with SSH key credentials or an HTTP basic auth secret, such as a username and password.

Add a Private CA to Repositories

To add a private CA to Helm chart repositories, you must add a base64 encoded copy of the CA certificate in DER format to the spec.caBundle field of the chart repo, such as openssl x509 -outform der -in ca.pem | base64 -w0. Instructions are the same for both Git-based and HTTP-based repositories:

  1. Click ☰. Under Explore Cluster in the left navigation menu, select a cluster.

  2. In the left navigation menu on the Cluster Dashboard, click Apps  Repositories.

  3. Find the row associated with the Git or HTTP-based repository you want to add a private CA to, and click ⋮ > Edit YAML.

  4. Set the caBundle value, as in the following example:

    [...]
    spec:
      caBundle:
    MIIFXzCCA0egAwIBAgIUWNy8WrvSkgNzV0zdWRP79j9cVcEwDQYJKoZIhvcNAQELBQAwPzELMAkGA1UEBhMCVVMxCzAJBgNVBAgMAkNBMRQwEgYDVQQKDAtNeU9yZywgSW5jLjENMAsGA1UEAwwEcm9vdDAeFw0yMTEyMTQwODMyMTdaFw0yNDEwMDMwODMyMT
    ...
    nDxZ/tNXt/WPJr/PgEB3hQdInDWYMg7vGO0Oz00G5kWg0sJ0ZTSoA10ZwdjIdGEeKlj1NlPyAqpQ+uDnmx6DW+zqfYtLnc/g6GuLLVPamraqN+gyU8CHwAWPNjZonFN9Vpg0PIk1I2zuOc4EHifoTAXSpnjfzfyAxCaZsnTptimlPFJJqAMj+FfDArGmr4=
    [...]
Helm chart repositories with authentication

The Repo.Spec contains a disableSameOriginCheck value. This value allows you to bypass the same origin checks, sending the repository Authentication information as a Basic Auth Header with all API calls. This is not recommended but can be used as a temporary solution in cases of non-standard Helm chart repositories, such as those that have redirects to a different origin URL.

To use this feature for an existing Helm chart repository, follow previous steps up to edit the YAML. On the spec portion of the YAML file, add disableSameOriginCheck and set it to true.

[...]
spec:
  disableSameOriginCheck: true
[...]

Helm Compatibility

Only Helm 3 compatible charts are supported.

Refresh Chart Repositories

The Refresh button can be used to sync changes from selected Helm chart repositories on the Repositories page.

To refresh a chart repository:

  1. Click ☰ > Cluster Management.

  2. Find the name of the cluster whose repositories you want to access. Click Explore at the end of the cluster’s row.

  3. In the left navigation menu on the Cluster Dashboard, click Apps  Repositories.

  4. Use the toggle next to the State field to select all repositories, or toggle specified chart repositories to sync changes.

  5. Click Refresh.

  6. The ⋮ at the end of each chart repository row also includes a Refresh option, which can be clicked to refresh the respective repository.

Non-Airgap Rancher installations upon refresh will reflect any chart repository changes immediately and you will see the State field for updated repositories move from In Progress to Active once the action is completed.

Airgap installations where Rancher is configured to use the packaged copy of Helm system charts (useBundledSystemChart=true) will only refer to the system-chart repository that comes bundled and will not be able to be refreshed or synced.

Deploy and Upgrade Charts

To install and deploy a chart:

  1. Click ☰ > Cluster Management.

  2. Find the name of the cluster whose charts you want to access. Click Explore at the end of the cluster’s row.

  3. In the left navigation menu on the Cluster Dashboard, click Apps  Charts.

  4. Select a chart, and click Install.

Rancher and Partner charts may have extra configurations available through custom pages or questions.yaml files. However, all chart installations can modify the values.yaml and other basic settings. After you click Install, a Helm operation job is deployed, and the console for the job is displayed.

To view all recent changes, click Apps  Recent Operations in the left navigation menu. From there you can view the calls, conditions, events, and logs.

After installing a chart, you can view it by clicking Apps  Installed Apps in the left navigation menu. You can upgrade or delete the installation, and see further details. Upgrading uses the same forms and values as you saw during inital installation.

Most Rancher tools have additional pages located in the toolbar below the Apps section to help manage and use the features. These pages include links to dashboards, forms to easily add Custom Resources, and additional information.

If you are upgrading your chart using Customize Helm options before upgrade, and your chart contains immutable fields, using the --force option may result in errors. This is because some objects in Kubernetes can’t be changed after they’re created. To prevent this error:

  • Use the default upgrade option (i.e don’t use --force).

  • Uninstall the existing chart and install the upgraded chart.

  • Delete the resources with immutable fields from the cluster before performing a forced upgrade.

Legacy Apps

The upgrade button isn’t available for legacy apps on the Apps  Installed Apps page.

If you want to upgrade an installed legacy app, the legacy feature flag must be turned on. This flag is automatically turned on if you had a legacy app already running before you upgraded Rancher.

  1. Enable the legacy feature flag, if it isn’t enabled already.

  2. Click ☰ > Cluster Management.

  3. Find the name of the cluster whose apps you want to access. Click Explore at the end of the cluster’s row.

  4. Click Legacy  Project  Apps.

If you don’t see Apps listed under Legacy  Project, click the project/namespace search bar in the top navigation and select the relevant project from the dropdown menu.

To upgrade legacy multi-cluster apps:

  1. Click ☰.

  2. Under Legacy Apps, click Multi-cluster Apps.

Limitations

Dashboard apps or Rancher feature charts can’t be installed using the Rancher CLI.