Installation guide

3-3
Installing the Driver
New Installations
For new installations of any of the operating systems supported, it
is possible, if not desireable, to install the operating system on an
array. This provides a more robust system, since failure of a drive
won’t cause the system to stop running.
Any such installation requires that the redundant array be created
prior to installing the operating system. Adaptec SCSI RAID
controllers provide two ways to do this, by starting (also called
booting) the system using the Adaptec CD, or by using the tools
built into the on-board firmware on the controller.
While it is beyond the scope of this guide as to which RAID type to
use for this application; you may want some guidance. The
following condensed table may offer help. For more details, consult
external resources detailing relative performance vs. desireable
characteristics for the various RAID types.
RAID
Type
Minimum
Number
of Drives
Properties
0 2 Not redundant - do not use RAID 0 for this
application if you want the protection afforded
by redundancy.
1 2 only Fast writes and reads, equivalent to the transfer
rate of the constituent drives.
5 3 Comparable read speed but rather slow write
speed compared to constituent drives.
10 4 Requires multiples of 2, starting with 4. Provides
the speed of a RAID 0 with the redundant
protection of a RAID 1.
50 6 Requires a minimum of 6 drives. Provides greater
efficiency in drive usage than the RAID 10.
R2N2 RAID IG.BOOK Page 3 Monday, September 9, 2002 12:01 PM