How to fix Application not found in Kubernetes

# List all Application resources across all namespaces
kubectl get applications -A

# List only in argocd namespace (default)
kubectl get applications -n argocd

# Describe the specific application
kubectl describe application my-app -n argocd

# Check if argocd namespace exists
kubectl get namespace argocd

# Check if ArgoCD pods are running
kubectl get pods -n argocd

# Expected pods should include:
# - argocd-application-controller-0
# - argocd-server-...
# - argocd-repo-server-...

# Check logs for errors in the application controller
kubectl logs -n argocd -l app.kubernetes.io/name=argocd-application-controller --tail=50

# Verify the application-controller is watching the argocd namespace
kubectl logs -n argocd deployment/argocd-application-controller | grep -i "argocd namespace"

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: my-app
  namespace: argocd              # CRITICAL: must be argocd namespace
spec:
  project: default               # Must match an AppProject in same namespace
  source:
    repoURL: https://github.com/my-org/my-repo
    targetRevision: main
    path: helm/my-chart            # Path in Git repo
  destination:
    server: https://kubernetes.default.svc
    namespace: production          # Target namespace for deployed app (different from metadata.namespace)
  syncPolicy:
    automated:
      prune: true
      selfHeal: true

kubectl apply -f application.yaml

# Verify creation
kubectl get application my-app -n argocd

# Dry-run validation
kubectl apply -f application.yaml --dry-run=client

# Check for schema violations
kubectl apply -f application.yaml --dry-run=server

# Validate against CRD schema
kubectl explain application.spec

# Check if there are events/warnings
kubectl describe application my-app -n argocd

# Edit the argocd-cmd-params-cm ConfigMap
kubectl edit configmap argocd-cmd-params-cm -n argocd

# Add or modify these keys:
applicationInstanceLabelKey: argocd.argoproj.io/instance
application.instanceLabelKey: argocd.argoproj.io/instance
application.resourceTrackingMethod: annotation

apiVersion: argoproj.io/v1alpha1
kind: AppProject
metadata:
  name: default
  namespace: argocd
spec:
  sourceRepos:
  - '*'
  destinations:
  - namespace: '*'
    server: '*'

kubectl rollout restart deployment/argocd-server -n argocd
kubectl rollout restart statefulset/argocd-application-controller -n argocd

# Stream logs in real-time while applying the manifest
kubectl logs -f -n argocd statefulset/argocd-application-controller

# In another terminal, apply the application
kubectl apply -f application.yaml

# Look for lines like:
# "error processing application"
# "failed to sync"
# "cannot access repository"

kubectl patch deployment/argocd-application-controller -n argocd --type json -p '[{"op": "add", "path": "/spec/template/spec/containers/0/args/-", "value": "--loglevel=debug"}]'

# Check configured repositories
kubectl get secret -n argocd | grep repository

# For public repos, ensure the repoURL is correct:
argocd repo list

# For private repos, verify credentials exist:
kubectl describe secret <repo-secret-name> -n argocd

# Test connectivity from repo-server pod
kubectl exec -it -n argocd argocd-repo-server-0 -- sh
# Inside the pod:
cd /tmp && git clone https://github.com/your-org/your-repo

argocd repo add https://github.com/your-org/your-repo --username <user> --password <token>