https://drive.google.com/file/d/1M-MKnd4hDLPYinQxEzi_PH4Pttub2MeK/view?usp=sharing

1. Understanding RAID

What is RAID?

RAID (Redundant Array of Independent Disks) combines multiple physical disks into a single logical unit for:

RAID Levels Overview

Level Name Pros Cons Use Case
RAID 0 Striping ⚡ Fastest read/write ❌ No redundancy (1 disk fail = total data loss) Video editing, gaming, temp data
RAID 1 Mirroring ✅ Full redundancy 💾 50% capacity loss Critical system disks
RAID 5 Striping + Parity ✅ 1-disk fault tolerance ⏳ Write penalty General-purpose storage
RAID 6 Striping + Double Parity ✅ 2-disk fault tolerance ⏳ High write penalty Large archival storage

⚠️ RAID ≠ Backup: RAID protects against disk failure, not data deletion/corruption.

2. Creating RAID-0 (Striping)

Prepare Disks

# Create partitions on 2 disks (e.g., /dev/sdb, /dev/sdc)
sudo fdisk /dev/sdb
# Commands: n → p → 1 → [Enter] → [Enter] → t → fd (Linux RAID) → w

sudo fdisk /dev/sdc
# Same steps → /dev/sdc1

sudo partprobe    # Reload partition table
lsblk             # Verify sdb1, sdc1

💡 Partition Type fd: Marks partition for RAID (required for safety).

Create RAID-0 Array

# Create RAID-0 with 2 disks
sudo mdadm -C /dev/md0 -l 0 -n 2 /dev/sdb1 /dev/sdc1

# Verify
cat /proc/mdstat    # Shows active RAID-0
sudo mdadm -D /dev/md0    # Detailed RAID info
lsblk               # Shows /dev/md0

Format and Use RAID

sudo mkfs.ext4 /dev/md0
sudo mkdir /raid0
sudo mount /dev/md0 /raid0
df -hT              # Verify mounted as ext4

# Test performance
cd /raid0
touch {1..20}
cal > cal.txt