Having a store (edge) cluster join the datacenter (hub)
Allow ACM to deploy the store application to a subset of clusters
A store (“ATLANTA”) is installed on the hub cluster by default. This feature is interesting if you want to see how ACM can manage a remote cluster to install the same application on a different cluster.
The way we apply this is through the managedClusterGroups block in
managedClusterGroups: - name: store clusterSelector: matchLabels: clusterGroup: raleigh matchExpressions: - key: vendor operator: In values: - OpenShift
Any cluster joined with the label
clusterGroup=raleigh will be assigned the policies that deploy the store app to them.
Deploy a store cluster
Rather than provide instructions on creating a store cluster it is assumed
that an OpenShift cluster has already been created. Use the
openshift-install program provided at cloud.redhat.com
There are a three ways to join the store to the datacenter.
- Using the ACM user interface
- Using the
- Using the
Store setup using the ACM UI
After ACM is installed a message regarding a “Web console update is available” may be displayed. Click on the “Refresh web console” link.
On the upper-left side you’ll see a pull down labeled “local-cluster”. Select “All Clusters” from this pull down. This will navigate to the ACM console and to its “Clusters” section
Select the “Import cluster” option beside the highlighted Create Cluster button.
On the “Import an existing cluster” page, enter the cluster name and choose Kubeconfig as the “import mode”. Add the tag
site=store Press import. Done.
Using this method, you are done. Skip to the section Store is joined but ignore the part about adding the site tag.
Store setup using
cm(cluster management) command-line tool. See details here
Obtain the KUBECONFIG file from the edge/store cluster.
On the command-line login into the hub/datacenter cluster (use
oc loginor export the KUBECONFIG).
Run the following command:
cm attach cluster --cluster <cluster-name> --cluster-kubeconfig <path-to-KUBECONFIG>
Skip to the section Store is joined
Store setup using
You can also use
clusteradm to join a cluster. The following instructions explain what needs to be done.
clusteradm is still in testing.
To deploy a edge cluster you will need to get the datacenter (or hub) cluster’s token. You will need to install
clusteradm. On the existing datacenter cluster:
clusteradm get token
When you run the
clusteradmcommand above it replies with the token and also shows you the command to use on the store. So first you must login to the store cluster
Then request to that the store join the datacenter hub
clusteradm join --hub-token <token from clusteradm get token command > <store cluster name>
Back on the hub cluster accept the join request
clusteradm accept --clusters <store-cluster-name>
Skip to the next section, Store is joined
Store is joined
That’s it! Go to your store (edge) OpenShift console and check for the open-cluster-management-agent pod being launched. Be patient, it will take a while for the ACM agent and agent-addons to launch. After that, the operator OpenShift GitOps will run. When it’s finished coming up launch the OpenShift GitOps (ArgoCD) console from the top right of the OpenShift console.