Argo CD - Changing a Live Manifest

Summary: How to change a live manifest in argocd.
Date: 27 February 2025

In this post I'll show you how to change a manifest for a live application in Argo CD. This is useful when you need to make a quick change to a resource that is managed by Argo CD. In the last few months I've used this for changing all sorts of things, like image versions, resource limits and timeout settings for the liveness probe.

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. It follows the GitOps pattern of using Git repositories as the source of truth for defining the desired application state. It is implemented as a controller that continuously monitors running applications and compares the current, live state against the desired target state (as specified in the Git repository).

With a live manifest, I mean the manifest for a resource that is managed by Argo CD and running in the kubernetes cluster. This could be a Deployment, a Service, a ConfigMap, or any other resource that is part of an application that is synced by Argo CD. Changing the manifest is done from the GUI of Argo CD.

Follow these steps to change a live manifest, in this example we'll change a deployment:

• Log into the Argo CD GUI.
  • If you don't have direct access to the GUI, you can setup a port-forward to the Argo CD server and access the GUI through a local port:
    • kubectl port-forward deployment/argo-cd-argocd-server 8080
• Now go the Argo CD application that has the deployment you want to change.
  • Optional for larger environments: In the application, set the view to “Tree” and search for the deployment you want to change.
• Click on the deployment you want to change.
• In the deployment details, scroll down to the “Live Manifest” tab.
• Click on the “Edit” button.
• In the editor, make the changes you want to make to the manifest.
• Click on the “Save” button.
• Argo CD will now apply the changes to the live deployment.

In the top, you can check the Events tab to see the progress of the change. Once the pod is started you can check the logs in the “Logs” tab.

And if you're not happy with the result, you can simply click the “Sync” button in the top right corner of the deployment details. This will sync all the settings from the git repository to the live deployment, effectively rolling back the changes you made.