Helm Install, Upgrade and Rollback

Application Deployment / Guide 21 of 44 / Intermediate

• Kubernetes1.36.4
• Cluster4 nodes
• Runtimecontainerd 2.2.6
• CNICalico v3.32.1
• TimeAbout 16 min

Helm 3 has no Tiller and stores each release revision as a Secret of type helm.sh/release.v1 in the release's own namespace. That is why helm list is namespaced, why deleting a namespace destroys the release history with it, and why anyone with Secret read access in that namespace can read the release.

This guide includes

Use this when a chart has to be installed, changed and rolled back under time pressure. This matters because Helm keeps every revision as a Secret in the namespace - which is what makes a rollback one command instead of a redeploy.

• scaffolding a readable chart with helm create
• rendering it locally with helm template, sending nothing to any cluster
• installing it, and reading the release, its revision and its status
• upgrading with different values and then taking it straight back
• finding the release state stored as sh.helm.release.v1 Secrets

Before you start

• Helm 3 installed. helm version --short on this cluster reports v3.18.5.
• The session creates a chart with helm create, installs it as release web in namespace ckad-helm, upgrades it, rolls it back, and uninstalls it.

1. 1

   A chart you can read

2. 2

   Render it without a cluster

3. 3

   Install, and look at the release

4. 4

   Upgrade, then take it back

5. 5

   Where the state actually lives

Official sources

• Helm documentation
• Helm - Charts
• Helm 3 release storage