Everything about Helm Part1
Helm Charts Made Simple
When we work with Kubernetes, most applications need a bunch of objects like:
Each of these objects requires a YAML file and we usually deploy it using:
kubectl apply -f <filename>Here’s the problem: if the application is big and has many objects, things get messy. Even if we combine all YAMLs in one file, troubleshooting errors is tough. Also, Kubernetes doesn't see the app as a single unit; it handles each object individually.
This is where Helm comes in. Helm is a package manager for Kubernetes. It bundles all the objects your application needs into a single package—like buying a ready-made kit instead of separate parts!
Why Helm is awesome:
- Easy installation:
helm install <app_name> <chart_name>deploys everything at once. - Easy upgrade: Instead of updating each object manually, just use:
helm upgrade <app_name> <chart_name> - Rollback: Something went wrong after an update?
helm rollback <app_name> <revision>fixes it. - Uninstallation: Deletes all objects with one command:
helm uninstall <app_name>
How Helm Works:
- Chart: A template containing all YAMLs your app needs.
- Release: The deployed version of the chart.
- Values:
values.yamlfile that sets parameters for your app.
Think of it like installing a game on your computer: instead of downloading the game, libraries, and settings separately, you install a ready-made package that handles everything.
Why Helm Matters:
Helm changes how we manage Kubernetes apps. Instead of treating an app as separate objects, we see it as a single unit. This not only saves effort but also reduces errors.
#Helm_Charts #Kubernetes #OpenShift #DevOps #containers #cnf
The Evolution of Helm
In the last post, we talked about Helm as a powerful tool for managing Kubernetes apps. Today, let’s look at Helm's evolution and its versions.
Helm Versions: Helm 2 vs Helm 3
Helm 2:
- It relied on something called Tiller, an agent that communicated with the K8s cluster. Tiller required very high privileges, which could cause security issues.
- Helm 2 used revision numbers to track chart updates. The problem was it only compared old vs new charts, ignoring any manual changes in the cluster. Rollbacks also ignored manual edits.
Helm 3:
- Tiller was removed. Helm now interacts directly with the K8s cluster using RBAC (Role-Based Access Control), which is safer.
- Helm 3 uses a 3-way strategic merge patch—it compares the old chart, new chart, and live state. This way, any manual changes are considered during updates or rollbacks.
In short, Helm 3 is more secure and smarter at handling updates and rollbacks, making it the go-to version today.
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