New Installations - Adaptec RAID 2120S Installation Manual

New Installations

For new installations of any of the operating systems supported, it
is possible, if not desirable, to install the operating system on an
array. This provides a more robust system when using a redundant
array, 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.
It is beyond the scope of this presentation as to which RAID type to
use for this application. But, since the user may want some
guidance, the following condensed table may offer help. For more
details, consult external resources detailing relative performance
vs. desirable characteristics for the various RAID types.
Minimum
RAID Number
Type of Drives
0 2
1 2 only
5 3
10 4
50 6
Properties
Not redundant - do not use RAID 0 for this
application if you want the protection afforded
by redundancy.
Fast writes and reads, equivalent to the transfer
rate of the constituent drives.
Comparable read speed but rather slow write
speed compared to constituent drives.
Requires multiples of 2, starting with 4. Provides
the speed of a RAID 0 with the redundant
protection of a RAID 1.
Requires a minimum of 6 drives. Provides greater
efficiency in drive usage than a RAID 10.
Installing the Driver
3-5