Learn GitOps with ArgoCD - ArgoCD UI & CLI Basics

#Introduction

ArgoCD is installed and you've already logged in for the first time in episode 4. But ArgoCD isn't just a "pretty dashboard" — it's two faces of one machine: the UI for visualization and inspection, and the CLI for automation and precise control. Mastering both means you can move fast in the UI to understand, and be efficient in the CLI to act.

In this episode we'll dissect the ArgoCD UI section by section, then explore the core CLI commands that will accompany you throughout this series.

#Exploring the ArgoCD UI

#Dashboard Overview

After logging in, the first page is Applications. This is the control center: each card represents one Application with sync and health status indicators. Green means Synced and Healthy; orange indicates OutOfSync or Progressing; red is Degraded or failed. From here you can filter, search, and click into an application for more detail.

#Application View

The application detail page has important tabs:

App Details — Git source (repo, path, branch) and destination (cluster, namespace).
Resources — the managed resources, with their sync and health status.
Live Manifest / App Manifest — the manifest actually in the cluster (live) vs the one in Git (desired).
Diff — the difference comparison between the two, complete with additions and deletions highlighted.
Events / Logs — Kubernetes events and container logs directly from the UI.

#Tree View vs Network View

Two ways to look at relationships between resources:

Tree view (default) — parent-child hierarchy: Application → Deployment → ReplicaSet → Pod. Great for seeing dependency chains.
Network view — visualizes Services and connections between resources; useful for verifying Service exposure and networking.

Tip

When debugging, start from the Tree view to find which resource is failing, then open Events on that pod. This pattern breaks a big problem into small, focused steps.

#Live Manifest and Diff

The feature that sets ArgoCD apart from plain kubectl get: ArgoCD keeps two versions of every manifest. Click the Diff tab to see exactly what differs between the manifest in Git and what's running in the cluster. This is the visual answer to the question "why is the status OutOfSync?"

#Mastering the ArgoCD CLI

The UI is great for exploration, but the CLI is the tool for speed and automation.

argocd login localhost:8080 --insecure
argocd context
argocd context localhost:8080

argocd context shows the saved contexts; switch the active context with argocd context <name> — useful when managing several ArgoCD instances.

#Core Commands

Command	Function
`argocd app list`	List all Applications with their status
`argocd app get <app>`	Full details of an Application
`argocd app sync <app>`	Run a synchronization
`argocd app history <app>`	Deployment history (revisions)
`argocd app rollback <app> <id>`	Return to a specific revision
`argocd app diff <app>`	Show the diff vs Git

A practical example:

Application inspection workflow

argocd app list
argocd app get api
argocd app diff api
argocd app sync api
argocd app history api

Warning

argocd app sync only works if an Application has been created. For this series' lab, we'll create the first Application in episode 6 — so there's nothing to sync yet. Don't panic if argocd app list is still empty.

Some habits that make working with ArgoCD much more efficient:

Filter applications by label in the application list (e.g. filter environment=production), rather than scanning manually.
Search for resources directly from the Resources page with the search field.
Bookmark frequently visited application pages in your browser; ArgoCD URLs can be shared and bookmarked.
Use the CLI for automation, keep the UI for investigation — don't open the UI for things that only need a single CLI command.
Combine argocd app get with --show-operation when you want to see the details of the last sync operation.

#Closing

You're now fluent in using ArgoCD's two faces:

UI: dashboard, application view, tree vs network view, live manifest, diff, events and logs.
CLI: login, context, app list, app get, app sync, app history, app rollback.
Navigation tips: label filtering, resource search, bookmarks, and CLI for automation.

The UI and CLI are mastered; only one thing is missing: an application to manage. In episode 6 we'll create your first Application — prepare a Git repository containing manifests, create the Application via the UI wizard and the CLI, then do the first sync and verify the result in Kubernetes. See you there!