HP StorageWorks XP Fast Recovery Solution administration guide: Windows Server 2003 (B9552-96004, September 2005)

40 HP StorageWorks XP Fast Recovery Solution for Windows Server 2003: Administration Guide
11. In the LUN management window, create one Command Device LUN
(CDEV) of at least 36 MB (larger is OK but wastes space) for each
server. This LUN must be mapped to a port that is visible to the server.
The CDEV LUN is used for interpreting commands and cannot be used
for data.
To designate a LUN as a command device:
Right click on the LUN and select Command Device ON.
Command Device LUNs can be any number but are customarily
assigned a number near the end of the available range. You can use a
VSC volume for a Command Device, but do not use a LUSE volume.
12. In the LUN management window, add LUNs to the new host groups.
For Exchange, you will need a minimum of two production volumes:
one for Mailstore (shared) and one for log files (storage group level).
You must create at least the same number of identical recovery
LUNs to match the number of production LUNs. The recovery
LUNs must be the same emulation type (OPEN-3, OPEN-9 etc.)
and the same size in GB as the production LUNs. Recovery LUNs
MUST be in a host group named “SVOL”.
To add a LUN:
Click the LUN you wish to define in the right panel. Select an LDEV
in the lower right panel. Then click Add LU Path. A confirmation
dialog pops up; click OK and the LUN is added with a path to the
selected LDEV. Click Apply to confirm the added LUN.
Windows limits LUNs to the range of 00 to FE, so be sure not to use a
LUN number above FE.
Windows 2000 requires a LUN 0 in order for LUNs greater than 7 to
be recognized by the OS. Windows Server 2003 with SCSIPort
Miniport Driver requires a LUN 0 in order to recognize any additional
LUNs.