1. Create array
RAID1 example:
mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdX /dev/sdY
2. Configuration
Save config:
mdadm --detail --scan >> /etc/mdadm.conf
3. Filesystem
mkfs.ext4 /dev/md0
4. Monitor
cat /proc/mdstat
Quick checklist
[ ] Steps completed
[ ] Config updated
[ ] Service tested
[ ] Restart/rollback ready
[ ] Logs checked