HP D5970A - NetServer - LCII Installation And User Manual page 85

Chapter 4
4. Check the Write Cache box if you want this logical drive to use Write
Back caching.
This improves performance but puts data at risk.
You should have a battery backup unit or uninterruptable power supply if
selecting this feature.
5. Check the Init Drive box if you want this logical drive to be fully
initialized at the conclusion of the configuration.
HP recommends checking this option.
6. If this is the first logical drive, select a stripe size.
This setting will apply to all logical drives on this controller.
The selection for stripe size will automatically set the appropriate cache
size.
7. Click the Add Drive button to register the new logical drive.
8. Click the LUN Mapping tab to continue with the configuration.
9. Or, repeat the process above to set up additional logical drives, then click
the LUN Mapping tab when you're done.
Refer to LUN Mapping Tab in the following sections for LUN Mapping
instructions.
NOTE
In Manual Configuration, the Add Logical Drive functions
very similar to what was shown above. RAID Assistant shows
you the disk arrays and logical drives and allows you to add to
the configuration without risking existing data.
LUN Mapping Overview
RAID Controllers use host ports to connect to one or more Host Bus Adapters
(HBAs) in one or more host computer systems. Mapping assigns Logical Unit
Numbers (LUNs) to the logical drives of the RAID Controller and makes the
logical drives (or system drives) available (or unavailable) to one or more host
ports. The LUN assignments are made on a per host port basis and are
independent of the assignments on other host ports. Logical drives may be
assigned only one LUN per host port. However, if a LUN is not assigned to a
logical drive on a particular host port, then the logical drive is inaccessible to that
host port.
Configuration
79