Install raidtools and mdadm, plus make sure the kernel has RAID support and that all necessary disk/IDE/SATA driver modules are loaded first. Also need fdisk and mke2fs.
For a simple RAID-1 array. Note that both drives need to be type "fd" in fdisk for type "Linux raid autodetect". To do this, run fdisk on /dev/sdb, /dev/sdc, etc.
bash-2.05b$ cat /etc/raidtab raiddev /dev/md0 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 32 persistent-superblock 1 device /dev/sdb1 raid-disk 0 device /dev/sdc1 raid-disk 1
/dev/md0 /home/public ext3 defaults 1 2
The /dev/md0 will need to be formatted as any other drive would be using mke2fs.
raidhotadd /dev/md0 /dev/sdc1and wait a very long time to resync the array.
Personalities : [linear] [raid0] [raid1] [raid5] [multipath] [raid6] [raid10] md0 : active raid1 sdc1 sdb1 156288256 blocks [2/2] [UU] unused devices: