Chapter 8. Disaster Recovery

Disaster recovery (DR) helps an organization to recover and resume business critical functions or normal operations when there are disruptions or disasters.

Red Hat OpenShift Data Foundation provides two options:

  • Regional-DR with Red Hat Advanced Cluster Management (RHACM)
  • Metro-DR (Stretched Cluster - Arbiter)

Regional-DR with RHACM

This Regional-DR solution provides an automated "one-click" recovery in the event of a regional disaster. The protected applications are automatically redeployed to a designated OpenShift Container Platform with OpenShift Data Foundation cluster that is available in another region. This release of Regional DR supports 2-way replication across two managed clusters located in two different regions or data centers.

Disaster Recovery features supported by Red Hat OpenShift Data Foundation require all of the following prerequisites in order to successfully implement a Disaster Recovery solution:

  • A valid Red Hat OpenShift Data Foundation Advanced entitlement
  • A valid Red Hat Advanced Cluster Management for Kubernetes subscription

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

For detailed requirements, see Regional-DR requirements and RHACM requirements.

Important

This is a developer preview feature and is subject to developer preview support limitations. Developer preview releases are not intended to be run in production environments and are not supported through the Red Hat Customer Portal case management system. 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 their availability and work schedules.

Metro-DR (Stretched Cluster - Arbiter)

In this case, a single cluster is stretched across two zones with a third zone as the location for the arbiter. This is a technology preview feature that is currently intended for deployment in the OpenShift Container Platform on-premises.

Note

This solution is designed to be deployed where latencies do not exceed 4 milliseconds round-trip time (RTT) between locations of the two zones residing in the main on-premise data centres. Contact Red Hat Customer Support if you are planning to deploy with higher latencies.

Prerequisites

  • Disaster Recovery features supported by Red Hat OpenShift Data Foundation require all of the following prerequisites in order to successfully implement a Disaster Recovery solution:

    • A valid Red Hat OpenShift Data Foundation Advanced entitlement
    • A valid Red Hat Advanced Cluster Management for Kubernetes subscription

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

  • To use the Arbiter stretch cluster,

    • You must have a minimum of five nodes across three zones, where:

      • Two nodes per zone are used for each data-center zone, and one additional zone with one node is used for arbiter zone (the arbiter can be on a master node).

    • All the nodes must be manually labeled with the zone labels prior to cluster creation.

      For example, the zones can be labeled as:

      • topology.kubernetes.io/zone=arbiter (master or worker node)
      • topology.kubernetes.io/zone=datacenter1 (minimum two worker nodes)
      • topology.kubernetes.io/zone=datacenter2 (minimum two worker nodes)

For more information, see:

Important

Metro-DR stretch cluster is a technology preview features and is subject to technology preview support limitations. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information, see Technology Preview Features Support Scope.