Chapter 2. Requirements for enabling Regional-DR

Subscription requirements

To know how subscriptions for OpenShift Data Foundation work, see knowledgebase article on OpenShift Data Foundation subscriptions.

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

Ensure that RHACM operator and MultiClusterHub is installed on the Hub cluster. See RHACM installation guide for instructions.

The managed clusters must have non-overlapping networks.

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.