Alternate index considerations

Data Replication for VSAM replicates alternate index path changes by identifying the target CICS file for the alternate index path.

As a result, it does not matter whether UPGRADE for the alternate index or UPDATE for the alternate index path is specified or not. Data Replication for VSAM simply repeats the source behavior at the target and the indexes are maintained or not maintained as they were at the source by relying on the source and target definitions matching.

Data Replication for VSAM allows for replicating VSAM spheres with alternate index paths that are used only for query access without requiring a file to be defined in the target CICS. When the replication mapping is defined or replication starts for the subscription, a warning is issued that indicates no file definition was found for the alternate index path in the target CICS. You can ignore this warning if the alternate index path access at the source is query-only. If an update is replicated for an alternate index path that is indicated in these warning messages, replication fails with an error.

If a file definition exists in the target CICS for the alternate index path, the definition must have the required attributes of enabled, readable, addable, updateable and deleteable.