Discover hosted clusters

The policy framework of Red Hat Advanced Cluster Management for Kubernetes (RHACM) goes far beyond simple compliance. With object-templates-raw and Go templates, you can:

• Query resources dynamically using the lookup function.
• Apply complex conditional logic.
• Iterate over multiple resources.
• Access ConfigMaps for external configuration.
• Execute actions based on a current cluster state.

Let's use all this power to create a robust and scalable auto-import solution.

In this lesson, you will:

• Enable the addon-discovery.
• Upload the addon-discovery to the managed cluster.
• Verify the hypershift-addon deployment.

Enable the hypershift add-on

After all your multicluster engine operator clusters are imported into RHACM, you need to enable the hypershift-addon for those managed multi-cluster engine operator clusters to discover the hosted clusters.

Default add-ons are installed into a different namespace in the previous procedures. Similarly, you install the hypershift-addon into a different namespace in a multi-cluster engine operator, so the add-ons agent for a multi-cluster engine operator local-cluster and the agent for RHACM, can work in a multi-cluster engine operator.

For ease of understanding, let's assume:

• Hosting Cluster Name (your MCE cluster): hc-site1-lab

• Hosted Cluster Agent Nodes: cluster-workload-linux

Step 1: Enable the addon-discovery

We will enable an add-on and disable metric collection to save resources.

oc patch addondeploymentconfig hypershift-addon-deploy-config -n multicluster-engine --type=merge -p '{"spec":{"agentInstallNamespace":"open-cluster-management-agent-addon-discovery"}}'
oc patch addondeploymentconfig hypershift-addon-deploy-config -n multicluster-engine --type=merge -p '{"spec":{"customizedVariables":[{"name":"disableMetrics","value": "true"},{"name":"disableHOManagement","value": "true"}]}}'

Step 2: Upload the addon-discovery to the managed cluster

Run the following command to enable a hypershift-addon for the multi-cluster engine operator of your managed MCE cluster. Example:

clusteradm addon enable --names hypershift-addon --clusters <managed-cluster-name>
oc get managedclusteraddon hypershift-addon -n <managed-cluster-name>
NAME               AVAILABLE   DEGRADED   PROGRESSING
hypershift-addon   True        False      False

Step 3: Verify hypershift-addon deployment

Now, go back to your MCE cluster (not the RHACM cluster) and verify that the hypershift-addon is installed in the namespace that you specified.

oc get deployment -n open-cluster-management-agent-addon-discovery

NAME                                 READY   UP-TO-DATE   AVAILABLE   AGE
cluster-proxy-proxy-agent            1/1     1            1           64m
hypershift-addon-agent               1/1     1            1           3m8s  <--- THIS ONE
klusterlet-addon-workmgr             1/1     1            1           64m
managed-serviceaccount-addon-agent   1/1     1            1           64m