HP StorageWorks XP Remote Web Console Software - Manual (Page 25)

URz pair will be restored quickly by the delta resync operation, you will not need to wait for a
long time before you can use the URz data volumes again.
Delta resync operation consists of the two processes; one is the process for the preparation before
the failure occurs, the other is the process for the recovery after the failure occurs.
•
Processing for the preparation before the failure occurs (see the next section)
•
Processing for the recovery after the failure occurs (see Switching the Master Journal Group
of URz )
Journal Obtain in TCz Synchronous Secondary Site
To perform delta resync operation when a failure occurs, you also need to obtain the journal data
in the TCz Synchronous secondary site of 3DC multi-target configuration. Specify the TCz
Synchronous R-VOL in TCz Synchronous secondary site as the primary data volume, and specify
the data volume in URz secondary site as the secondary data volume, in order to create a URz
pair for the delta resync operation.
When you create a URz pair for delta resync operation, the differential data of data volumes in
TCz Synchronous primary site and secondary site will be stored in the journal volumes in TCz
Synchronous secondary site as journal data. The following figure shows an example.
URz Delta Resync Operation 25