HP XP External Storage Software - Manual (Page 99)

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 ).
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.
Data that is not written by the host (for example, data written by XP Business Copy) is
asynchronously destaged to the external subsystem regardless of the Cache Mode setting.
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.
External Storage XP user guide for the XP12000, XP10000, SVS200 99