Script: Create Mirrored RAID Volume

As of late, I have been tasked with managing Mac servers.  Since a Mac server is really only slightly different than a Mac client, I use the same general methodologies and tools to manage them.  My Xserve hardware standard includes three identical hard disks.  What follows is a script intended to be used with the Casper Suite as a “before” script in a configuration.  It will create a mirrored RAID volume from two of the three drives.

#!/bin/sh
#
##### HEADER BEGINS #####
# scr_sys_createServerMirror.sh
#
# Created 20081230 by Miles A. Leacy IV
# miles.leacy@themacadmin.com
# Modified 20090421 by Miles A. Leacy IV
# Copyright 2009 Miles A. Leacy IV
#
# This script may be copied and distributed freely
# as long as this header remains intact.
#
# This script is provided "as is".  The author offers no warranty
# or guarantee of any kind.
# Use of this script is at your own risk.  The author takes no
# responsibility for loss of use, loss of data, loss of job,
# loss of socks, the onset of armageddon, or any other
# negative effects.
#
# Test thoroughly in a lab environment before use on production systems.
# When you think it's ok, test again.  When you're certain it's ok,
# test twice more.
#
# This script creates a mirrored RAID volume from the first two internal
# disks found.
# It is intended for use on Xserves with two or more identical internal disks.
# Run as a "before" script when imaging with The Casper Suite.
#
##### HEADER ENDS #####
i=0
diskcount=0

while [ $diskcount -lt 3 ]; do
if [ `diskutil info disk$diskcount | grep Internal | grep -c Yes` -gt 0 ] ;then
	if [ $i -eq 0 ] ; then
		raiddisk1=disk$diskcount
	fi
	if [ $i -eq 1 ] ; then
		raiddisk2=disk$diskcount
	fi
	let i++
fi
let diskcount++
done

diskutil createRAID mirror Server HD JHFS+ $raiddisk1 $raiddisk2