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 Container Storage provides two flavors:
Regional DR: This is a multi-cluster asynchronous replication of storage volumes across two OpenShift Container Storage clusters serving two Openshift Container Platform clusters. Any stateful application, including its stateless counterparts need some preparation prior to deploying the same on a peer cluster.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 firstname.lastname@example.org 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. Contact Red Hat Customer Support if you are planning to deploy with higher latencies.
To use the Arbiter stretch cluster,
Must have minimum of five nodes in 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 nodes must be manually labeled with 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)
This is a technology preview feature and is available only for deployment using local storage devices. 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.