How to Set Up Software RAID on Linux

How to Set Up Software RAID on Linux

Software RAID uses mdadm to combine multiple disks into a redundant array, protecting your Breeze data against drive failures without requiring a hardware RAID controller.

Common RAID Levels

• RAID 1 — mirroring, requires 2 disks, tolerates 1 failure
• RAID 5 — striping with parity, requires 3+ disks, tolerates 1 failure
• RAID 10 — mirrored stripes, requires 4 disks, best performance and redundancy

Creating a RAID 1 Array

sudo apt-get install -y mdadm

# Create the array from two disks
sudo mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sdb /dev/sdc

# Watch the build progress
cat /proc/mdstat

# Format and mount
sudo mkfs.ext4 /dev/md0
sudo mkdir -p /mnt/raid
sudo mount /dev/md0 /mnt/raid

Persisting the Configuration

sudo mdadm --detail --scan | sudo tee -a /etc/mdadm/mdadm.conf
sudo update-initramfs -u

Add to fstab

echo '/dev/md0 /mnt/raid ext4 defaults 0 2' | sudo tee -a /etc/fstab

Monitoring and Recovery

# Check array status
sudo mdadm --detail /dev/md0

# Replace a failed disk
sudo mdadm /dev/md0 --remove /dev/sdc
sudo mdadm /dev/md0 --add /dev/sdd

Always monitor RAID status on your Breeze — RAID is not a backup but a first line of defense against disk failure.