GitOps with ArgoCD

🚀 Introduction to GitOps with ArgoCD

As Kubernetes adoption grows, teams are constantly searching for reliable ways to manage complex deployments at scale. GitOps with ArgoCD is one such modern approach that leverages Git as the single source of truth for Kubernetes infrastructure and application state. In this blog, we’ll explore how ArgoCD simplifies continuous delivery, automates deployment, and empowers teams to embrace a declarative, version-controlled DevOps workflow.

📌 What is GitOps?

GitOps is a DevOps practice that uses Git repositories to store the desired state of your Kubernetes clusters. Any change to infrastructure or application configuration is made by committing changes to Git, which are then automatically applied to the cluster. This brings:

• Version control: Track every change.
• Auditability: Understand who changed what and when.
• Reproducibility: Easily roll back to a known state.

⚙️ What is ArgoCD?

ArgoCD is a lightweight, Kubernetes-native continuous delivery (CD) tool that automates the deployment of applications by syncing them with a Git repository. It ensures the live cluster state always matches the desired state defined in Git.

• Declarative setup using YAML.
• Auto-sync for continuous deployment.
• Rollback support with Git commit history.
• Visual UI for monitoring app health and status.

📦 Key Components of ArgoCD

• Application: Defines the source repo and the target cluster/namespace.
• Repository: Git repo where your Kubernetes manifests or Helm charts live.
• Sync: The process of aligning the live state with the desired state.
• Hooks: Custom actions like pre-sync or post-sync scripts.

🛠️ Installing ArgoCD on Kubernetes

To install ArgoCD on your Kubernetes cluster:

kubectl create namespace argocd

kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

This installs ArgoCD into the argocd namespace. You can then expose the ArgoCD API server using a LoadBalancer or port-forward:

kubectl port-forward svc/argocd-server -n argocd 8080:443

🔐 Accessing the ArgoCD UI

Once ArgoCD is running, access the UI at https://localhost:8080.

To get the initial admin password:

kubectl get secret argocd-initial-admin-secret -n argocd -o jsonpath="{.data.password}" | base64 -d

🚀 Deploying an Application with ArgoCD

Let’s deploy a sample app using ArgoCD. First, define an Application manifest like below:

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: guestbook
  namespace: argocd
spec:
  destination:
    namespace: default
    server: https://kubernetes.default.svc
  project: default
  source:
    repoURL: https://github.com/argoproj/argocd-example-apps
    targetRevision: HEAD
    path: guestbook
  syncPolicy:
    automated:
      prune: true
      selfHeal: true

Apply it using:

kubectl apply -f guestbook-app.yaml

🔄 Syncing and Monitoring Changes

ArgoCD constantly monitors the Git repository. If a change is detected in the repo, it will auto-sync the new state to the cluster (if auto-sync is enabled), or you can trigger it manually from the UI or CLI:

argocd app sync guestbook

🧠 Benefits of Using GitOps with ArgoCD

• Faster onboarding: All infrastructure is defined in Git.
• Disaster recovery: Restore environments from Git.
• Audit trail: Every change is tracked and attributed.
• Consistency: Prevents config drift across environments.

💡 Best Practices

• Use separate repos for environments (dev/stage/prod).
• Use ArgoCD Projects to isolate access and permissions.
• Secure ArgoCD API with SSO and RBAC.
• Monitor ArgoCD with Prometheus and Grafana.

📚 Bonus: ArgoCD vs FluxCD

Both ArgoCD and FluxCD are GitOps tools, but ArgoCD stands out with its rich web UI and app-centric design. FluxCD is more CLI-driven and works well for teams that prefer Git-based policy enforcement over UI control.

🔚 Conclusion

GitOps with ArgoCD is a game-changer for managing Kubernetes clusters at scale. It brings structure, traceability, and automation to the deployment process, while keeping everything stored safely in Git. Whether you’re running microservices or monolithic apps, ArgoCD ensures your deployments are predictable, auditable, and repeatable. Start small with a demo app and scale your GitOps journey with confidence!