Install. Upgrade. Undo.

Read the step before copying. Bash commands belong in Git Bash on Windows or Azure Cloud Shell set to Bash; PowerShell uses different syntax. A JSON, YAML, Bicep or application-code example belongs in the named file, not directly at the terminal prompt. Follow any shell-specific instructions below.

Keep the same terminal open so earlier variables remain available. Copy one complete command block without the terminal's $ prompt. A backslash continues a command onto the next line. If Bash shows a lone >, it is waiting for the rest of a quote, command or file block. Finish the complete block; if the paste was incomplete, press Ctrl+C and copy it again. Do not paste the next step into an unfinished command.

A line such as RG="training-group" stores a value without printing it. Output captured with $(...) is also stored; a blank screen alone does not prove failure. A sleep deliberately waits, and -o none suppresses normal output. Wait for your normal prompt, then run the step's checkpoint. After an error, stop and keep the exact command and message; later steps cannot repair a missing resource. Never share passwords, access tokens or secret values in a screenshot.

Helm packages Kubernetes manifests as a chart. Installing it creates a named release with numbered revisions. An upgrade adds a revision; a rollback applies an earlier retained revision's Helm-managed manifests and values as a new revision. This lab checks that a replica-count change reaches the cluster and that rollback restores it. In a real incident, also test the application: Helm cannot reverse changes to data or systems outside its release.

Undo, as a single line with a number in it.

If you still have the cluster from Your first AKS cluster, skip to Step 2. Otherwise recreate it with the identical command.

# Windows/Git Bash: stop it mangling /subscriptions/... arguments (harmless on macOS/Linux)
export MSYS_NO_PATHCONV=1

RG="campux-lab-aks-rg"
az group create -n "$RG" -l eastus

# same command as the first-cluster lab: free control plane, one small node
# if Azure says this size "is not allowed in your subscription", the same error lists the sizes
# that are; pick a 2-vCPU one from that list (Standard_D2as_v4 worked for us in October 2026)
az aks create -n campux-aks -g "$RG" \
  --tier free \
  --node-count 1 \
  --node-vm-size Standard_D2as_v4 \
  --enable-managed-identity \
  --generate-ssh-keys

az aks get-credentials -n campux-aks -g "$RG"
helm version --short

podinfo is a small, well-known demo chart built for exactly this kind of exercise — a real Deployment and Service with values worth changing. Install it as a release named shop-release, starting deliberately small.

Commands inside $(...) save their output in a variable. Check the printed identifier or the checkpoint before continuing.

helm repo add podinfo https://stefanprodan.github.io/podinfo
helm repo update

kubectl create namespace helmdemo

# Choose one published chart version and keep it for both changes.
helm search repo podinfo/podinfo --versions | head
CHART_VERSION="$(helm search repo podinfo/podinfo --versions -o json | python3 -c 'import json,sys; print(json.load(sys.stdin)[0]["version"])')"
echo "$CHART_VERSION"

helm install shop-release podinfo/podinfo \
  --namespace helmdemo \
  --version "$CHART_VERSION" --wait --timeout 5m \
  --set replicaCount=1

helm list -n helmdemo

Confirm the pod is real and reachable, then look at the release the way Helm sees it — as a single named, versioned object, not as "whatever is currently in the namespace."

This block includes a deliberate wait. Leave this terminal open until the normal prompt returns; a wait is not proof that access has propagated.

kubectl rollout status deployment/shop-release-podinfo -n helmdemo --timeout=5m
kubectl get pods -n helmdemo
kubectl get deploy,svc -n helmdemo

# fullname template = release name + chart name, since "shop-release" does not already contain "podinfo"
kubectl port-forward -n helmdemo svc/shop-release-podinfo 9898:9898 &
sleep 2
curl -s localhost:9898/ | head -c 200
echo
kill %1

helm status shop-release -n helmdemo

Ship a real change — triple the replica count — and watch Kubernetes actually create the new pods before you check anything with Helm.

helm upgrade shop-release podinfo/podinfo \
  --namespace helmdemo \
  --version "$CHART_VERSION" --wait --timeout 5m \
  --set replicaCount=3

kubectl rollout status deployment/shop-release-podinfo -n helmdemo --timeout=5m
kubectl get pods -n helmdemo

helm status shop-release -n helmdemo
helm history shop-release -n helmdemo

One command, one number. Do not stop at "the command exited zero" — check the pod count and the values Helm actually stored, the same way you would in an incident at three in the morning.

helm rollback shop-release 1 -n helmdemo --wait --timeout 5m

kubectl rollout status deployment/shop-release-podinfo -n helmdemo --timeout=5m
kubectl get pods -n helmdemo

helm history shop-release -n helmdemo
helm get values shop-release -n helmdemo

helm uninstall removes resources managed by this release, subject to retention policies. Then remove this lab's namespace and dedicated resource group. Confirm the group contains no unrelated work first.

helm uninstall shop-release -n helmdemo
kubectl delete namespace helmdemo

az group delete -n campux-lab-aks-rg --yes --no-wait
az group exists -n campux-lab-aks-rg      # -> false once complete

You installed a pinned chart version as a named release, upgraded its replica count, and restored a retained revision. You verified the Deployment became ready and checked Helm's stored values. That is evidence for this lab's replica-count rollback; a production recovery also needs application and data checks.