Verify Drive – Fix Errors – through controller utility
or replace with new drive
Check the numbers for the bad drive
cat /proc/scsi/scsi
Remove bad drive
echo “scsi remove-single-device 0 0 2 0” > /proc/scsi/scsi
Check to make sure it’s gone
cat /proc/scsi/scsi
Add good drive
echo “scsi add-single-device 0 0 2 0” > /proc/scsi/scsi
Check to make sure it’s there
cat /proc/scsi/scsi
Fdisk the drive as needed (set type (t) to linux raid auto-detect (fd))
fdisk /dev/sdc
If using an drive from a previous RAID
mdadm –zero-superblock /dev/sdc1
Add the new drive to the software RAID
mdadm –add /dev/md0 /dev/sdc1
Check rebuild progress
cat /proc/mdstat