HP SureStore E SAN Manager LUN Management Administrator's Guide

Logical Unit Numbers Greater Than 7 181
Advanced SAN
Administration
Logical Unit Numbers Greater Than 7
When using disks in filter compatibility mode or non-disk devices such as tapes, SCSI
bridges, and tape libraries regardless of mode, SCSIPORT’s restriction of eight LUNs per
target (numbers 0–7) prevents SAN Manager LM and other applications and drivers from
seeing devices with LUNs greater than 7.
To configure SCSIPORT to support logical unit numbers greater than 7, use the LargeLUNs
registry setting.
Caution Editing the registry incorrectly may cause serious problems that will require
you to reinstall Windows NT. For more information about editing the registry,
see your Microsoft documentation.
Table 5 LargeLUNs Registry Setting
Path:
Value Name:
Value Type:
Value:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
<HBA driver name>\Parameters\Device[N]
LargeLuns
REG_DWORD
1
Note The number N appended to the device name is optional. It identifies
the ScsiPort device instance (adapter) that the setting applies to.
Omitting the number applies the setting to all adapters controlled by
the HBA driver.
The <HBA driver name> corresponds to the file name of your HBA
driver. For example, the path for users with the HP SAN Manager LM
QLogic HBA driver (trqladrv) is:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
trqladrv\Parameters\Device[N]