Container Service for Kubernetes:Deploy applications using ACK One GitOps

Step 1: Add a Git repository and deploy the application

1. Log on to the ArgoCD console.

Open the ArgoCD server domain in a browser. For the domain name, see Log on to the GitOps system.

On the ArgoCD homepage, click LOGIN VIA ALIYUN.

2. Add a source Git repository.

In the left-side navigation pane, choose Settings > Repositories and click + CONNECT REPO.

Fill in the repository details and click CONNECT.

The CONNECTION STATUS column shows Successful when the repository is connected.

3. Create an ArgoCD application.

On the Applications page, click + NEW APP and fill in the application details. ArgoCD pulls the Helm chart from the source Git repository and deploys it to the default namespace of the specified cluster.

Click CREATE at the top of the panel.

The Applications page now shows the echo-server-app application.

4. Sync the application to the cluster.

Click SYNC below the application to trigger deployment.

When Status shows Healthy and Synced, the application is running on the target cluster. Click the application name to see the topology and status of all Kubernetes resources.

Step 2: Verify the deployment

Use the Fleet instance kubeconfig to run these commands and confirm the application is running.

1. List clusters associated with the Fleet instance:

kubectl amc get managedcluster

Expected output:

Name         Alias             HubAccepted
cd****      ackpro-cluster2      true
ce****      ackpro-cluster1      true    // The cluster in which the application is deployed.

The output lists all clusters registered with the Fleet instance. ce**** (ackpro-cluster1) is where the application was deployed.

2. Check resources in the target cluster:

kubectl amc get all -n default -m ce****

The -m flag targets a specific managed cluster.

Expected output:

Run on ManagedCluster ce**** (ackpro-cluster1)
NAME                               READY   STATUS    RESTARTS   AGE
pod/echo-server-5cf54bdbcb-jv58k   1/1     Running   0          59m

NAME                  TYPE           CLUSTER-IP        EXTERNAL-IP    PORT(S)          AGE
service/echo-server   LoadBalancer   192.XX.XX.XX      39.XX.XX.XX   8080:31769/TCP   59m        21d

NAME                          READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/echo-server   1/1     1            1           59m

The pod shows 1/1 Running and the LoadBalancer Service has an external IP assigned. The application is ready to receive traffic.

3. Verify the application version:

curl http://39.XX.XX.XX:8080/version

Expected output:

"Hello Echo Server v1.0"

The application is running at v1.0.

Step 3: Update the application

1. Push an image tag change to Git.

In the Git repository, change the pod image tag from v1.0 to v2.0.

Due to the tag change in the Git repository, the ArgoCD application displays OutOfSync.

2. Review the diff.

Click the OutOfSync icon to view what changed.

3. Sync the update.

Click SYNC. After the sync completes, the pod image tag is v2.0.

4. Verify the updated version:

curl http://39.XX.XX.XX:8080/version

Expected output:

"Hello Echo Server v2.0"

Step 4: Roll back to a previous version

After the application is updated to v2.0, ArgoCD retains the original ReplicaSet for rollback.

1. Confirm both ReplicaSets exist in the cluster:

kubectl amc get replicaset  -n default -m ce****

Expected output:

Run on ManagedCluster ce**** (ackpro-cluster1)
NAME                     DESIRED   CURRENT   READY   AGE
echo-server-55664c4677   1         1         1       26m    // The version is v2.0.
echo-server-5cf54bdbcb   0         0         0       109m   // The version is v1.0.

2. Roll back to v1.0.

On the application page, click HISTORY AND ROLLBACK to see all historical versions.

Select v1.0 and click Rollback.

The pod image tag reverts to v1.0. Because the cluster state now differs from the Git repository (which still has v2.0), the application status changes to OutOfSync. Click SYNC to initiate a synchronization task.

ArgoCD automatically synchronizes information from the source Git repository.

Step 1: Log on to the ArgoCD server

1. Get the ArgoCD server load balancer IP:

kubectl get svc -nargocd argocd-server -ojsonpath='{.status.loadBalancer.ingress[0].ip}'

2. Get the admin password:

kubectl -nargocd get secret argocd-initial-admin-secret -ojsonpath='{.data.password}' |base64 -d

3. Log on:

argocd login <argocd server lb ip>
Username: admin
Password:
'admin:login' logged in successfully
Context '<argocd server lb ip>' updated

Step 2: Add a Git repository

argocd repo add https://github.com/AliyunContainerService/gitops-demo.git --name echo-server

Expected output:

Repository 'https://github.com/AliyunContainerService/gitops-demo.git' added

Verify the repository is connected:

argocd repo list

Expected output:

TYPE  NAME  REPO                                                       INSECURE  OCI    LFS    CREDS  STATUS      MESSAGE  PROJECT
git         https://github.com/AliyunContainerService/gitops-demo.git  false     false  false  false  Successful           default

Step 3: Check available clusters

argocd cluster list

Expected output:

SERVER                          NAME                    VERSION  STATUS   MESSAGE                                                  PROJECT
https://10.XX.XX.XX:XX      ce****-ackpro-cluster1               Unknown  Cluster has no applications and is not being monitored.
https://10.XX.XX.XX:XX      cd****-ackpro-cluster2               Unknown  Cluster has no applications and is not being monitored.
https://kubernetes.default.svc  in-cluster                       Unknown  Cluster has no applications and is not being monitored.

ACK One automatically synchronizes information about newly associated clusters to ArgoCD, so any cluster added to the Fleet instance appears here.

Step 4: Create and deploy the application

1. Create the application:

argocd app create echo-server --repo https://github.com/AliyunContainerService/gitops-demo.git --path manifests/helm --revision one-demo --dest-namespace default --dest-server https://10.0.XX.XX:6443

Expected output:

application 'echo-server' created

2. Sync the application to pull the configuration from Git and deploy it to the target cluster:

argocd app sync echo-server