GitOps with ArgoCD: Automate Kubernetes Deployments | DevOpsNess

GitOps with ArgoCD: Automating Kubernetes Deployments

GitOps revolutionizes how we deploy applications. This guide shows you how to implement GitOps with ArgoCD.

What is GitOps?#

GitOps uses Git as the single source of truth for infrastructure and application deployments.

Principles:

Declarative configuration
Version controlled
Automated synchronization
Continuous reconciliation

Installing ArgoCD #

bash.bash

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

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

Creating an Application #

yaml.yaml

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: my-app
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://github.com/user/repo
    targetRevision: HEAD
    path: k8s/
  destination:
    server: https://kubernetes.default.svc
    namespace: default
  syncPolicy:
    automated:
      prune: true
      selfHeal: true
    syncOptions:
    - CreateNamespace=true

Sync Policies #

Manual Sync #

yaml.yaml

syncPolicy:
  syncOptions:
  - CreateNamespace=true

Automated Sync #

yaml.yaml

syncPolicy:
  automated:
    prune: true
    selfHeal: true
  syncOptions:
  - CreateNamespace=true

Multi-Environment Setup #

yaml.yaml

# Production
apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: app-prod
spec:
  source:
    repoURL: https://github.com/user/repo
    path: k8s/prod
  destination:
    namespace: production

---
# Staging
apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: app-staging
spec:
  source:
    repoURL: https://github.com/user/repo
    path: k8s/staging
  destination:
    namespace: staging

App of Apps Pattern #

yaml.yaml

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: root-app
spec:
  source:
    repoURL: https://github.com/user/repo
    path: argocd/apps
  destination:
    server: https://kubernetes.default.svc
    namespace: argocd
  syncPolicy:
    automated:
      prune: true

Best Practices #

Use separate repos for config and code
Implement RBAC for ArgoCD
Use AppProjects for organization
Monitor sync status
Implement approval workflows for production

Conclusion #

ArgoCD makes GitOps simple and powerful. Start with manual sync and gradually move to automated workflows as you gain confidence.

For GitOps with ArgoCD: Automating Kubernetes Deployments, define pre-deploy checks, rollout gates, and rollback triggers before release. Track p95 latency, error rate, and cost per request for at least 24 hours after deployment. If the trend regresses from baseline, revert quickly and document the decision in the runbook.

Keep the operating model simple under pressure: one owner per change, one decision channel, and clear stop conditions. Review alert quality regularly to remove noise and ensure on-call engineers can distinguish urgent failures from routine variance.

Repeatability is the goal. Convert successful interventions into standard operating procedures and version them in the repository so future responders can execute the same flow without ambiguity.