HP Netserver L Server series - Manual (Page 37)

Chapter 6 Installing Mass Storage Devices
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Hot-Swap Mass Storage Cage
Low-Profile and Half-Height Drives
SCSI hot-swap hard disk drives come in two heights: the 1-inch low-profile drive
and the 1.6-inch half-height drive.
Ultra2 drives are LVD (low voltage differential) drives, which allow the
integration of the differential drivers and receivers into SCSI drive controllers.
Ultra2 technology provides increased signal quality, and ensures the same data
integrity as the previous high voltage differential designs at a reduced cost.
An added benefit of the low voltage design is that the SCSI bus cable can extend
up to 12 meters.
CAUTION Do not mix devices with high voltage differential (HVD)
drivers and receivers and devices with SE, Ultra2 or
multimode drivers and receivers on the same SCSI bus.
I/O circuits used by devices with SE, Ultra2 or multimode
drivers and receivers do not operate at HVD levels and should
never be exposed to HVD environments. If you mix SCSI SE
and SCSI Ultra2 devices, system performance will be
adversely affected. For best performance, use only Ultra2
devices.
Filler Panels
When you have fewer drives than the hot-swap mass storage cage supports, a
1-inch filler panel must be inserted in each empty disk location. Filler panels
ensure that drive cage has the proper ventilation and air flow. Remove the filler
panel when you insert a new drive.
CAUTION The filler panels serve an important purpose by helping the
internal components ventilate and preventing excessive
electromagnetic radiation. If these fillers are left out of the
drive shelves, thermal damage and/or excessive EMI could
occur.
Drive Spacers
When your drive cage holds a mix of 1-inch and 1.6-inch drives, you may need to
add 0.5-inch drive spacers. The drive spacer fills the gap between adjacent drives