This document discusses using GitOps and Helm for configuration management of Kubernetes. It begins with an overview of configuration management and why GitOps is useful. It then demonstrates Flux for continuous delivery to synchronize a Git repo and Kubernetes cluster. Helm is demonstrated as a package manager for Kubernetes that helps manage complex applications and sharing of charts. Finally, it shows how the Flux Helm Operator can automate Helm chart releases defined as Kubernetes custom resources.

1. Config management for
Kubernetes: GitOps + Helm
Tomasz Tarczyński, Gigaset

2. Agenda
@ttarczynski
1. Configuration Management
2. Why GitOps
3. Demo: Flux
4. Demo: Helm
5. Demo: Flux Helm Operator

3. Configuration Management
@ttarczynski
● Infrastructure as a Code
● GIT – as a single source of truth
● Tools:
Ansible / Chef / Puppet / Salt

4. Puppet
@ttarczynski
● DSL: a simple and constrained language
● Declarative: describe the desired state
● Templates: ERB
● Modules: public and private
● Code / data separation: Hiera

5. Kubernetes
@ttarczynski
● Control plane provides a Declarative API
● Declare the desired state
● Control plane makes sure that the actual
state converges to the desired state

6. Kubernetes: Why GitOps
@ttarczynski
● Can we declare all the state in GIT?
And expect the system to converge.
● Can we have something like modules?

7. Kubernetes: Why GitOps
@ttarczynski
● Configuration Management:
Declarative vs Imperative

8. GitOps: How
@ttarczynski
Kubernetes
API
push
container images
kubectl apply
pull

9. GitOps: How
@ttarczynski
● Flux CD: a Continuous Delivery tool
○ Runs in the cluster
○ Synchronizes the cluster state with a GIT repo
○ CNCF sandbox project

10. GitOps: How
@ttarczynski
Kubernetes
API
push
container images
kubectl apply
pull

11. GitOps: How
@ttarczynski
Kubernetes
API
Flux CD
push
container images
commit
kubectl apply
sync
pull
images metadata
apply / delete

12. GitOps
@ttarczynski
Demo
https://github.com/ttarczynski/gitops-demo

13. GitOps: Why Helm
@ttarczynski
● We declared all the state in GIT
● But can we have something like modules?

14. GitOps: Why Helm
@ttarczynski
● Helm: The package manager for Kubernetes
○ find, share, and use software built for Kubernetes

15. GitOps: Why Helm
@ttarczynski
● Manage complexity: describe complex apps

16. GitOps: Why Helm
@ttarczynski
● Manage complexity: describe complex apps
● Easy updates: in-place upgrades and custom hooks

17. GitOps: Why Helm
@ttarczynski
● Manage complexity: describe complex apps
● Easy updates: in-place upgrades and custom hooks
● Simple sharing: public / private repo

18. GitOps: Why Helm
@ttarczynski
● Manage complexity: describe complex apps
● Easy updates: in-place upgrades and custom hooks
● Simple sharing: public / private repo
● Rollbacks: roll back to an older version with ease

19. Helm
@ttarczynski
Demo
https://github.com/ttarczynski/gitops-demo

20. GitOps + Helm
@ttarczynski
● Flux Helm Operator:
○ automates Helm Chart releases
○ Kubernetes custom resource named HelmRelease
○ charts are released as specified in HelmRelease

21. Credit: https://fluxcd.io
GitOps + Helm

22. GitOps + Helm
@ttarczynski
Demo
https://github.com/ttarczynski/gitops-demo

23. GitOps
@ttarczynski
● The entire system is described declaratively
● The canonical desired system state is
versioned (with Git)
● Approved changes to the desired state are
automatically applied to the system
● Software agents ensure correctness

24. Agenda
@ttarczynski
1. Configuration Management
2. Why GitOps
3. Demo: Flux
4. Demo: Helm
5. Demo: Flux Helm Operator

25. GitOps: Flux docs
@ttarczynski
● fluxcd.io
● docs.fluxcd.io
● github.com/fluxcd/helm-operator-get-started
● github.com/ttarczynski/gitops-demo

26. Thanks!
Tomasz Tarczynski
@ttarczynski