Raid allows for data to be sparsed over multiple disks and give security to your data as one (or more) disks can fail and data integrity will still remain.
49.1 Initialize disks¶
mdadm --zero-superblock /dev/sd[b-e]
wipefs -a /dev/sd[b-e]
49.2 Create raid¶
You can set level to get more performance or more redundancy
This command will create a raid level 10.
mdadm --create /dev/md0 --level=10 --raid-devices=4 /dev/sd[b-e]
Check raid types and benefits here: http://www.raid-calculator.com/
Save your newly created raid configuration for next reboots:
mdadm --detail --scan > /etc/mdadm/mdadm.conf
- cat /proc/mdstat: shows raid status and progress
mdadm software raid will trigger a complete check every sunday at 1am. Be aware of that as it will lower diks io speed a lot.