Application lifecycle management

After the cluster manager is installed, you could install the application management components to the hub cluster.

Architecture

application lifecycle management architecture

For more details, visit the multicloud-operators-subscription GitHub page.

Prerequisite

You must meet the following prerequisites to install the application lifecycle management add-on:

  • Ensure kubectl and kustomize are installed.

  • Ensure the open-cluster-management cluster manager is installed. See Cluster Manager for more information.

  • Ensure the open-cluster-management klusterlet is installed. See Klusterlet for more information.

Install via Clusteradm CLI tool

Ensure clusteradm CLI tool is installed. Download and extract the clusteradm binary. For more details see the clusteradm GitHub page.

$ clusteradm
Usage:
  clusteradm [command]
...

Deploy the subscription operators to the hub cluster.

$ kubectl config use-context ${CTX_HUB_CLUSTER}
$ clusteradm install hub-addon --names application-manager
Installing built-in application-manager add-on to the Hub cluster...
$ kubectl -n open-cluster-management get deploy multicluster-operators-subscription --context ${CTX_HUB_CLUSTER}
NAME                                READY   UP-TO-DATE   AVAILABLE   AGE
multicluster-operators-subscription   1/1     1            1           25s

Create the open-cluster-management-agent-addon namespace on the managed cluster.

$ kubectl create ns open-cluster-management-agent-addon --context ${CTX_MANAGED_CLUSTER}
namespace/open-cluster-management-agent-addon created

Deploy the subscription add-on in corresponding managed cluster namespace on the hub cluster.

$ kubectl config use-context ${CTX_HUB_CLUSTER}
$ clusteradm addon enable --names application-manager --clusters ${MANAGED_CLUSTER_NAME}
Deploying application-manager add-on to managed cluster: <managed_cluster_name>.
$ kubectl -n ${MANAGED_CLUSTER_NAME} get managedclusteraddon # kubectl -n cluster1 get managedclusteraddon
NAME                  AVAILABLE   DEGRADED   PROGRESSING
application-manager   True

Check the the subscription add-on deployment on the managed cluster.

$ kubectl -n open-cluster-management-agent-addon get deploy --context ${CTX_MANAGED_CLUSTER}
NAME                  READY   UP-TO-DATE   AVAILABLE   AGE
application-manager   1/1     1            1           103s

Install from source

Clone the multicloud-operators-subscription repository.

git clone https://github.com/open-cluster-management-io/multicloud-operators-subscription
cd multicloud-operators-subscription

Deploy the subscription operators to the hub cluster.

$ kubectl config use-context ${CTX_HUB_CLUSTER}
$ make deploy-hub
$ kubectl -n open-cluster-management get deploy multicluster-operators-subscription --context ${CTX_HUB_CLUSTER}
NAME                                READY   UP-TO-DATE   AVAILABLE   AGE
multicluster-operators-subscription   1/1     1            1           25s

Create the open-cluster-management-agent-addon namespace on the managed cluster and it’s optional if clusteradm is used which create the ns during join action.

$ kubectl create ns open-cluster-management-agent-addon --context ${CTX_MANAGED_CLUSTER}
namespace/open-cluster-management-agent-addon created

Deploy the subscription add-on in corresponding managed cluster namespace on the hub cluster.

$ kubectl config use-context ${CTX_HUB_CLUSTER}
$ make deploy-addon
$ kubectl -n ${MANAGED_CLUSTER_NAME} get managedclusteraddon # kubectl -n cluster1 get managedclusteraddon
NAME                  AVAILABLE   DEGRADED   PROGRESSING
application-manager   True

Check the the subscription add-on deployment on the managed cluster.

$ kubectl -n open-cluster-management-agent-addon get deploy --context ${CTX_MANAGED_CLUSTER}
NAME                  READY   UP-TO-DATE   AVAILABLE   AGE
application-manager   1/1     1            1           103s

What is next

After a successful deployment, test the subscription operator with a helm subscription. Run the following command where the examples/helmrepo-hub-channel locates at here:

kubectl apply -f examples/helmrepo-hub-channel --context ${CTX_HUB_CLUSTER}

After a while, you should see the subscription is propagated to the managed cluster and the Helm app is installed. By default, when a subscribed applications is deployed to the target clusters, the applications are installed in the coresponding subscription namespace. To confirm, run the following command:

$ kubectl get subscriptions.apps --context ${CTX_MANAGED_CLUSTER}
NAME        STATUS       AGE    LOCAL PLACEMENT   TIME WINDOW
nginx-sub   Subscribed   107m   true
$ kubectl get pod --context ${CTX_MANAGED_CLUSTER}
NAME                                                   READY   STATUS      RESTARTS   AGE
nginx-ingress-47f79-controller-6f495bb5f9-lpv7z        1/1     Running     0          108m
nginx-ingress-47f79-default-backend-7559599b64-rhwgm   1/1     Running     0          108m