GitOps w/ Flux

What is GitOps?

• A set of practices built around using Git as your system’s source of truth.
• GitOps requires the desired state of the system to be stored in version control.
• GitOps and Kubernetes typically go hand-in-hand the mission here being your “system” consists of kubernetes-based infrastructure and the applications on top.
• Define your apps and k8s infra declaratively with k8s manifest files.

Benefits of GitOps

• Traceability - Knowing who did what
• Transparency - Knowing “what” is there
• Knowledge Sharing via Git - allows people to easily understand your system from code rather than digging into the system itself (think using kubectl commands instead of reading manifest files from one location)
• Deployments are easier - you only have to make commits to a branch on git
• Tooling has matured to:
• Perform state management for your cluster + resources
• Perform the actually deployment of resources to the cluster & cloud infrastructure

GitOps Flow

1. Operator (Human/Bot) creates a branch
2. Operator (Human/Bot) creates a Pull Request
3. PR Merged and approved
4. GitOps tool polls for changes (ArgoCD)
5. Changes are applied to the cluster

Flux v2

• Flux v2 is a GitOps tool that synchronizes configuration from a git repository into a given Kubernetes Cluster
• Ability to Deploy
• Kustomize
• Helm Charts
• Yaml Manifests
• Flux has a CLI tool for installing and interacting with Flux

CRDs and Flux

• Flux is stateless and uses Custom Resources (CR) to store its state
• Custom Resource Definitions are a way to extend the functionality of Kubernetes by allowing you to create your own api objects and operators
• Allows multiple ways to interact with Flux
• Flux CLI
• Applying kubernetes objects
• Apply changes to the Git Repo

Flux Architecture