Chapter 2. Requirements for enabling Regional-DR

  • You must have three OpenShift clusters that have network reachability between them:

    • Hub cluster where Advanced Cluster Management for Kubernetes (RHACM operator), ODF Multicluster Orchestrator and OpenShift DR Hub controllers are installed.
    • Primary managed cluster where OpenShift Data Foundation, OpenShift DR Cluster controller, and applications are installed.
    • Secondary managed cluster where OpenShift Data Foundation, OpenShift DR Cluster controller, and applications are installed.

  • Ensure that you have installed RHACM operator and MultiClusterHub on the Hub cluster and logged on to the RHACM console using your OpenShift credentials. See RHACM installation guide for instructions.

    Find the Route that has been created for the Advanced Cluster Manager console: 

    $ oc get route multicloud-console -n open-cluster-management -o jsonpath --template="https://{.spec.host}/multicloud/clusters{'\n'}"

    Example Output: 

    https://multicloud-console.apps.perf3.example.com/multicloud/clusters

    After logging in using your OpenShift credentials, you should see your local cluster imported.

  • Ensure that you have either imported or created the Primary managed cluster and the Secondary managed clusters using the RHACM console.

    To connect the managed OpenShift cluster and service networks using the Submariner add-ons, you need to validate that the two clusters have non-overlapping networks by running the following commands for each of the managed clusters. 

    $ oc get networks.config.openshift.io cluster -o json | jq .spec

    Example output for cluster1 (for example, ocp4perf1): 

    {
  "clusterNetwork": [
    {
      "cidr": "10.5.0.0/16",
      "hostPrefix": 23
    }
  ],
  "externalIP": {
    "policy": {}
  },
  "networkType": "OpenShiftSDN",
  "serviceNetwork": [
    "10.15.0.0/16"
  ]
}

    Example output for cluster2 (for example, ocp4perf2): 

    {
  "clusterNetwork": [
    {
      "cidr": "10.6.0.0/16",
      "hostPrefix": 23
    }
  ],
  "externalIP": {
    "policy": {}
  },
  "networkType": "OpenShiftSDN",
  "serviceNetwork": [
    "10.16.0.0/16"
  ]
}

    For more information, see Submariner add-ons documentation.

  • Ensure that the Managed clusters can connect using Submariner add-ons. After identifying and ensuring that the cluster and service networks have non-overlapping ranges, install the Submariner add-ons for each managed cluster using the RHACM console and Cluster sets. For instructions, see Submariner documentation.

  • Ensure OpenShift Data Foundation 4.9 or greater is installed on each of the managed clusters.

    • For information about the OpenShift Data Foundation deployment, refer to your infrastructure specific deployment guides (for example, AWS, VMware, Bare metal, Azure).

    • Validate the successful deployment on each managed cluster with the following command: 

      $ oc get storagecluster -n openshift-storage ocs-storagecluster -o jsonpath='{.status.phase}{"\n"}'

    If the status result is Ready on the Primary managed cluster and the Secondary managed cluster, then continue with enabling mirroring on the managed clusters.