GitOps with Argo CD · Module 01

GitOps and Argo CD Basics

What GitOps is and why the pull model is safer, how Argo CD is built and installed, how an Application ties a Git path to a cluster, and how to read sync and health status.

Practice interactively →

What you will learn

• Explain the four GitOps principles and the difference between push-based CD and pull-based GitOps
• Describe the Argo CD components and install it, then log in with the CLI
• Create, sync and delete an Application from a Git repository
• Read sync and health status, use diff and refresh, and explain common OutOfSync causes

Lessons

1. What is GitOps

   GitOps runs a system from a Git repository: the desired state is declared in Git, and an agent in the cluster keeps pulling and reconciling the real state towards it.

2. Argo CD architecture and installation

   Argo CD runs as a few controllers in the argocd namespace: the API server, the repo server that renders manifests, and the application controller that compares and syncs.

3. Your first Application

   An Application is a CRD that says which repo, path and revision to deploy, to which cluster and namespace, inside which project.

4. Sync status, health and diff

   Sync status says whether the cluster matches Git; health says whether the objects actually work. Diff, refresh and history help you see why.