HP StorageWorks XP Remote Web Console Software - Manual (Page 57)

NOTE:
URz does not support operations in which one primary data volume is copied to more than one secondary
data volume, or more than one primary data volume is copied to one secondary data volume.
Because URz operates on volumes rather than on files, multivolume files require special attention. For
complete duplication and recovery of a multivolume file (e.g., a large database file which spans several
volumes), make sure that all volumes of the file are copied to URz secondary data volume, and use URz
to ensure update sequence consistency across this group of secondary data volume.
Duplicate VOLSER (Volume Serial Number)
When you select Entire as the initial copy option, the URz initial copy operation copies the VOLSER of
the primary data volume to the secondary data volume, and therefore the primary data volume and
secondary data volume of the URz pair will have the same VOLSER. Since the host operating system
does not allow duplicate VOLSERs, the host system administrator must take precautions to prevent system
problems related to duplicate VOLSERs. For example, the URz secondary data volumes must be defined
in the system generation so they do not come online automatically (see WARNING below).
WARNING: If the volumes which will become URz secondary data volumes are physically attached to
the same system images as the production volumes which will become the URz primary data volumes, the
following problems can occur:
When a URz pair is released, the old secondary data volume is usually offline. When a host system is
IPL’d (initial program loaded), the operator will be offered both volumes and asked which volume should
be left offline − the old duplicate volser message. This can be confusing and is prone to error. To
avoid duplication of VOLSER,
1. Identify the volumes that will not be accessed by the host system.
2. Perform CHP OFF or some other operation to ensure that the volumes are inaccessible.
3. When performing IPL, you must perform LOAD CLEAR.
Logical Volume Types
The following DKC and DKU emulation types can be used for the URz software.
Table 10 Supported Emulation Types
Emulation Support type
DKC All CU images that can be used with XP disk array
DKU (Drive) All mainframe volumes that can be used with XP disk array
All DKC and DKU (drive) emulation types for XP disk array can be used for URz software. In URz, the
emulation types of primary and secondary data volumes are indicated.
The following CU emulation types can be used for MCUs (primary storage systems) and RCUs (secondary
storage systems): 3990-3, 3990-6, 3990-6E, 2105, 2107, A-65A2, H-65A2, A-65C1, A-65C2.
The CU emulation type of an MCU can be different from the CU emulation type of the corresponding RCU.
Notes:
• The CU emulation type 3990-6, 3990-6E, 2105, or 2107 is required for SMS I/O time stamping
of URz journals. If one of these CU emulation types is used, volumes of the 3380 emulation
type must not be used.
• The CU emulation type H-65A2 is used for the HITAC M series and supports all types of M
series volumes.
Hitachi Universal Replicator for z/OS user guide for XP12000/XP10000 Disk Arrays and SVS 200 57