RAID CONFIGURATION IN RHEL5

Create 3 partitions
eg: /dev/sda{8,9,10}
Label then ad Linux raid autodetect (fd)
partprobe

mdadm -C /dev/md0 -l 5 -n 3 /dev/sda{8,9,10}
(l=level, n=number of disk partitions)
mdadm -D /dev/md0 (to see details D=detail or --detail)
mdadm -f /dev/md0 /dev/sda9 (f=fail or --fail)
mdadm -D /dev/md0

Create new partition. eg: /dev/sda11
mdadm -a /dev/md0 /dev/sda11
In another tab check the buildig of raid by the below command
watch cat /proc/mdstat
mdadm -D /dev/md0

mdadm -r /dev/md0 /dev/sda9 (r=remove or --remove)

*mdadm -S /dev/md0 (S=stop or --stop)

mkdir /raid
mount /dev/md0 /raid (to make permanent make entry in /etc/fstab)