SRE Thailand Bootcamp

Week 10: GitOps — ArgoCD

Theme: Declarative deployment and sync with ArgoCD.

Learning Objectives

1. Explain GitOps principles (declarative, versioned, automated sync)
2. Install and configure ArgoCD
3. Manage application definitions via Git repositories
4. Implement sync strategies (auto-sync, prune, self-heal)

Reading Materials

• ArgoCD Documentation
• ArgoCD Getting Started
• ArgoCD Declarative Setup
• GitOps Principles (CNCF)
• ArgoCD Best Practices (Codefresh)
• Weave GitOps

Finger Exercises (choose 2)

1. Install ArgoCD in kind. Access the UI via port-forward. Change the admin password.
2. Create a Git repo with Kubernetes manifests for the Go app. Point ArgoCD at it. Verify auto-sync.
3. Simulate drift: manually edit a Deployment resource in the cluster. Watch ArgoCD self-heal.

Project

Create a GitOps repository (gitops-infra) separate from the app repo:

gitops-infra/
├── apps/
│   ├── go-app/
│   │   ├── deployment.yaml
│   │   ├── service.yaml
│   │   └── kustomization.yaml
│   └── python-worker/
│       ├── deployment.yaml
│       └── kustomization.yaml
├── infrastructure/
│   ├── prometheus/
│   ├── grafana/
│   ├── loki/
│   └── jaeger/
└── argo-apps/
    └── all-apps.yaml

• Use Kustomize for environment overlays: overlays/dev/, overlays/prod/
• Use Helm charts for infrastructure components
• Configure ArgoCD ApplicationSets to create apps from the repository
• Demonstrate:
  • Sync the stack to a dev cluster
  • Change an image tag in git, push, watch auto-sync
  • Rollback a bad deployment using argocd app rollback

Time Budget