Helm - Introduction and Concepts

Question 1

What is Helm sometimes called? And why?

Answer 1

Package Manager for Kubernetes.

Looks at Kubernetes objects as part of a big package, as a group.
Lets us treat our Kubernetes apps as apps instead of a collection of objects

Question 2

What are advantages of helm?

Answer 2

• we use a single command to install our app, no matter how many objects are needed (helm install wordpress …)
• helm adds automatically every object needed to Kubernetes
• we can customize the settings of our app at install time
• we have a single spot, where we keep all the values for the settings (value.yaml)

Question 3

What actions are on a basic level possible with Helm?

Answer 3

• install our app with a single command (helm install wordpress)
• upgrade our app (helm upgrade wordpress)
• rollback an upgrade (helm rollback wordpress)
• uninstall the app (helm uninstall wordpress)

Question 4

Where and how can you recognize the running operating system?

Answer 4

in /etc/* releases* the OS is listed

Question 5

How do we get from multiple yamls to helm charts?

Answer 5

• ## turn yamls files into template yamls

Question 6

What values get replaced by variables when creating templates for helm?

Answer 6

• values that might change between environments
  Llike an
• container image
• PV capacitry
• secret keys

The specified variable names will be used to fetch the values from the values.yaml

Question 7

What does a Helm chart consist of?

Answer 7

• values.yaml for variable-values
• templates for object-yamls

Question 8

What is included in the Chart.yaml file?

Answer 8

• Information about the chart itself.
• Name of the Chart
• charts version
• keywords associated with the application

Question 9

What is stored in Artifact Hub.io

Answer 9

Charts of other users
Called as a repository that stores helm charts

Question 10

How can you search the artifactHub.io?

Answer 10

helm search hub … (wordpress for wordpress charts)

Question 11

How can you add another repository to be searched for charts?

Answer 11

helm repo add bitnami https://charts.bitname.com/bitnami

-> helm search repo wordpress

Question 12

How can you install charts on your cluster?

Answer 12

helm install [release-name] [chart-name]

Question 13

What are installtions of a chart called? What are they?

Answer 13

release

Each release has a release-name

Each release, even of the same app is a separate thing.
helm install release-1 bitname/wordpress and helm install release-2 bitnami/wordpress create independent apps

Question 14

What are important helm commands?

Answer 14

• helm list
• helm uninstall my-release
• helm pull –untar bitname/wordpress (extracts tar-content once downloaded)
• ls wordpress

Question 15

With what command can you see all installed helm chart repositories?

Answer 15

helm repo list