Home > Workload Solutions > SAP > Guides > SAP HANA TDI Guides > Business Continuity and Disaster Recovery with Dell PowerMax Storage for SAP HANA TDI Deployments > Introduction
In this use case we extend use cases 1, 2, and 3 by adding other SAP application devices to the composite group to show the benefits of PowerMax consistency group technology. In this use case, an SAP ERP system on Oracle database is using an SAP LT replication server to replicate data in real time to the SAP HANA environment.
In a failover scenario, the consistency group technology ensures that you can restart the SAP ERP, the SAP LT replication server, and SAP HANA at the remote site to a consistent point in time. Thus, when the SAP LT replication jobs are manually restarted, replication from the SAP ERP system to SAP HANA can continue without tables having to be dropped and reloaded into SAP HANA to ensure data consistency between both systems.
The R1 devices in the source PowerMax system are replicated to the R2 devices in the target PowerMax system. While the replication is active writing to the R2 devices is not possible.
The following figure illustrates this use case:
Note: The dotted red circles represent a composite group containing SAP HANA persistence and the SAP application devices. Remote-site replication from the SAP ERP to SAP HANA using the SAP LT replication server occurs only when you fail over.