Chapter 10. Application failover between managed clusters

This section provides instructions on how to failover the busybox sample application. The failover method for Regional-DR is application based. Each application that is to be protected in this manner must have a corresponding DRPlacementControl resource and a PlacementRule resource created in the application namespace as shown in the Create Sample Application for DR testing section.

Procedure

  1. On the Hub cluster navigate to Installed Operators and then click Openshift DR Hub Operator.
  2. Click DRPlacementControl tab.
  3. Click DRPC busybox-drpc and then the YAML view.
  4. Add the action and failoverCluster details as shown in below screenshot. The failoverCluster should be the ACM cluster name for the Secondary managed cluster.

    DRPlacementControl add action Failover

    Image show where to add the action Failover in the YAML view

  5. Click Save.
  6. Verify that the application busybox is now running in the Secondary managed cluster, the failover cluster ocp4perf2 specified in the YAML file.

    $ oc get pods,pvc -n busybox-sample

    Example output:

    NAME          READY   STATUS    RESTARTS   AGE
    pod/busybox   1/1     Running   0          35s
    
    NAME                                STATUS   VOLUME                                     CAPACITY   ACCESS MODES   STORAGECLASS                  AGE
    persistentvolumeclaim/busybox-pvc   Bound    pvc-79f2a74d-6e2c-48fb-9ed9-666b74cfa1bb   5Gi        RWO            ocs-storagecluster-ceph-rbd   35s
  7. Verify that busybox is no longer running on the Primary managed cluster.

    $ oc get pods,pvc -n busybox-sample

    Example output:

    No resources found in busybox-sample namespace.
Important

Be aware of known Regional-DR issues as documented in Known Issues section of Release Notes.

If you need assistance with developer preview features, reach out to the ocs-devpreview@redhat.com mailing list and a member of the Red Hat Development Team will assist you as quickly as possible based on availability and work schedules.