The maximum number of pairs, The maximum, Number of pairs – HP StorageWorks XP Remote Web Console Software User Manual
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CAUTION:
Volumes containing a VMA (volume management area) cannot be used as journal
volumes. For detailed information about a VMA, see the HP StorageWorks LUN Security XP
Extension user guide.
explains emulation types and the capacity of volumes that can form pairs. For
details on the maximum number of pairs, see
.
Table 12 Specifications of Volumes That Can Form Pairs
Support specifications
Item
Same emulation type.
Emulation type
The same capacity.
Volume capacity
URz can copy data between volumes with the same emulation and capacity (for example, 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.
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
Support specifications
Item
Same emulation type.
Emulation type
Does not matter whether the capacity is the
same or different.
Volume capacity
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
Support specifications
Item
RAID1, RAID5, and RAID6 can coexist.
RAID configuration of data
volume and journal volume
RAID1, RAID5, and RAID6 can coexist in the same journal group.
The Maximum Number of Pairs
NOTE:
The number of pairs that can be created in a storage system is limited.
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 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 (that is, 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
Requirements and Restrictions for URz
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