HP StorageWorks XP Remote Web Console Software - Manual (Page 59)

The table below explains emulation types and the capacity of volumes that can form pairs. For details on
the maximum number of pairs, see “ Journal Group ” on page 62.
Table 12 Specifications of Volumes That Can Form Pairs
Item Support specifications
Emulation type Same emulation type.
Volume capacity The same capacity.
URz can copy data between volumes with the same emulation and capacity (e.g., 3390-3R to 3390-3R).
URz also supports the Virtual LVI/LUN feature of the XP storage system, enabling you to establish URz
pairs with custom-size emulation types as well as standard-size emulation types. When custom-size
emulation types are assigned to URz pairs, the secondary data volume must have the same capacity as
the primary data volume. The URz remote console software displays the emulation type of the primary
data volumes and secondary data volumes.
URz supports the Virtual LVI/LUN feature of the XP storage system, which allows you to configure
custom-size LDEVs which are smaller than standard-size LDEVs. When custom-size LDEVs are assigned to
a URz pair, the secondary data volume must have the same capacity as the primary data volume.
Table 13 on page 59 shows the emulation types and capacity of master and restore journal volumes
that can be used for a URz software.
Table 13 Journal Volume Specifications
Item Support specifications
Emulation type Same emulation type.
Volume capacity Does not matter whether the capacity is
the same or different.
Table 14 on page 59 shows the RAID level combination of data volume and journal volume in the
journal group that can be used for URz.
Table 14 RAID Level Configuration of URz
Item Support specifications
RAID configuration of data RAID1, RAID5, and RAID6 can coexist.
volume and journal volume
RAID1, RAID5, and RAID6 can coexist in the same journal group.
The Maximum Number of Pairs
Use the number of cylinders and bitmap areas to calculate the maximum number of pairs that can be
created in a storage system. The number of pairs that can be created in a storage system is limited.
• The number of cylinders:
The number of pairs of a primary data volume and a secondary data volume is limited by the number
of cylinders of the volumes to be paired (i.e., the capacity of the volume. If VLL is used, the number
of pairs depends on the number of cylinders specified by VLL.). The limit on the number of pairs is
applied to both the primary storage system and the secondary storage system. Table 15 on page 60
illustrates the number of cylinders according to each emulation type.
Hitachi Universal Replicator for z/OS user guide for XP12000/XP10000 Disk Arrays and SVS 200 59