Off-host processing consists of performing operations on application data on a host other than the one where the application is running. Typical operations include Decision Support Systems (DSS) and backup. In a VVR environment, off-host processing operations can be performed on the Secondary of the Replicated Data Set. This reduces the load on the application server, the Primary.
The model for data access on the Secondary is that you break off a mirror from each data volume in the RVG, perform the operation on the mirror, and then reattach the mirror while replication is in progress.