HP StorageWorks XP Remote Web Console Software - Manual (Page 82)

82 Configuring external LUs
When the external LU to be mapped has the VMA setting, IO Suppression mode is automatically set to
Disable.
CAUTION: To use the mapped external LU for products other than Flex Copy XP (such as Cache
LUN XP, Auto LUN XP, Continuous Access XP, Continuous Access XP Journal, and Business Copy
XP), set IO Suppression mode to Disable.
CAUTION: To set I/O Suppression mode to Disable, External Storage XP must be installed.
CAUTION: To set IO Suppression mode to Enable, Flex Copy XP must be installed.
• Cache Mode
Specifies if the write I/O from the host is propagated synchronously or asynchronously to the external
storage device (” External LU attributes set by mapping ” on page 20).
To propagate write I/Os from the host to the external array asynchronously, select Enable.
To propagate write I/Os from the host to the external array synchronously, select Disable.
If you set IO Suppression mode to Enable, Cache Mode is automatically set to Disable.
CAUTION: If you set Disable, Cache LUN XP’s bind mode cannot be set.
CAUTION: If you set the mapped LU to a mainframe-system emulation type, the host I/O is always
propagated asynchronously to the external LU, regardless of the Cache Mode setting.
• Start CU:LDEV
First CU:LDEV number in the series of mapped destination internal LDEVs. The default is “- : -”. Interval
also appears. The default is 0.
To have External Storage XP select the first CU:LDEV number for the mapped internal LDEV, leave the
default (“- : -”). External Storage XP searches for an available CU:LDEV number starting with 00:00,
and selects the first one it finds.
To specify the first CU:LDEV number and interval, click Select LDEV. The Select LDEV window
( Figure 49 ) appears.
• Alternate Path
Number of alternate paths automatically set when mapped. Values can be from 0 to 7. Default is 1.
CAUTION: If the specified number of alternate paths cannot be set, an error appears in the Preset
list.
• CLPR (see ” External LU attributes set by mapping ” on page 20)
When cache memory is partitioned using XP Disk/Cache Partition, you can select the CLPR used to
access the mapped LU from the list. The SLPR number that the selected CLPR belongs to appears on the
right of the list. However, when you select a mainframe emulation type in Emulation Type, you can only
select CLPRs belonging to SLPR number 0. The Limited check box appears on the right of the SLPR
number. To display only CUs defined for the selected SLPR, select the Limited check box. To display all
CUs, regardless of the SLPR, clear the check box. By default, the Limited check box is selected.
• Select LDEV button
Displays the Select LDEV window (
Figure 49 ) where you can select the first CU:LDEV number in the
series.