HP StorageWorks XP Remote Web Console Software - Manual (Page 30)

2-8 Chapter 3 Preparing for Universal Replicator z/OS Operations
Hitachi Universal Replicator for IBM /OS User’s Guide
• The primary storage system is the control unit in the primary storage
system which controls the primary data volume of the URz pairs and
master journal volume. The Storage Navigator remote console PC must be
LAN-attached to the primary storage system. The primary storage system
communicates with the secondary storage system via the dedicated remote
copy connections. The primary storage system controls the host I/O
operations to the URz primary data volume and the journal obtain
operation of the master journal volume as well as the URz initial copy and
update copy operations between the primary data volumes and the
secondary data volumes.
• The secondary storage system is the control unit in the secondary storage
system which controls the secondary data volume of the URz pairs and
restore journal volume. The secondary storage system controls copying of
journals and restoring of journals to secondary data volumes. The
secondary storage system assists in managing the URz pair status and
configuration (e.g., rejects write I/Os to the URz secondary data volumes).
The secondary storage system issues the read journal command to the
primary storage system and executes copying of journals. The secondary
Storage Navigator PC should be connected to the secondary storage
systems at the secondary site on a separate LAN. The secondary storage
systems should also be attached to a host system to allow sense
information to be reported in case of a problem with a secondary data
volume or secondary storage system and to provide disaster recovery
capabilities.
The USP V can function simultaneously as a primary storage system for one or
more primary data volumes and as a secondary storage system for one or
more secondary data volumes, provided the remote copy connections and
fibre-channel interface ports are properly configured. The URz software allows
you to specify the secondary storage system from the connected primary
storage system. URz operations can be performed on all LDEVs except for the
USP V command device. For further information on the USP V command
device, please refer to the Business Continuity Manager User and Reference
Guide.
Note: When you configure a URz journal group pair, you have to specify the
serial numbers of primary storage systems and secondary storage systems.
You have to specify the different serial numbers of primary storage system
and secondary storage system for the same URz journal group pair. If you
have to specify the same serial number, please contact your Hitachi account
team.
Logical DKC (LDKC)
The USP V storage system controls the CU (Control Unit) by dividing the CUs
in to groups of 255 CUs. Each group is a storage system that logically exists in
USP V (logical storage system). These groups are called a “logical DKC” or an
“LDKC (Logical disk controller)”. There are 2 LDKCs in the USP V storage
system and number “00” and “01” is assigned to each LDKC.