RAID (Redundant Array of Independent Disks) recovery is one of the most complex data recovery procedures. Understanding how it works helps you make better decisions when facing array failures.
What Is RAID?
RAID combines multiple hard drives into a single logical unit for performance, redundancy, or both:
- RAID 0: Striping for speed, no redundancy — any single drive failure loses all data
- RAID 1: Mirroring — data duplicated across drives
- RAID 5: Striping with parity — survives one drive failure
- RAID 6: Double parity — survives two drive failures
- RAID 10: Combined mirroring and striping
How RAID Recovery Works
- Assessment: Identify which drives failed and failure type
- Drive-level recovery: Repair individual failed drives if needed
- Imaging: Create sector-by-sector copies of all drives
- Array reconstruction: Determine stripe size, parity rotation, and drive order
- Data extraction: Rebuild the file system and recover data
Common RAID Failure Scenarios
- Multiple simultaneous drive failures
- Failed rebuild after replacing a drive
- RAID controller failure
- Accidental reconfiguration or initialization
- Power surge damaging multiple drives
RAID Recovery Costs
- RAID 1 (mirror): Starts at $500 — essentially single drive recovery
- RAID 5/6: Starts at $800 — requires array reconstruction
- RAID 0: Starts at $800 — no redundancy makes it complex
- Large arrays (8+ drives): $1,500+ depending on complexity
Critical: Don't Attempt DIY RAID Recovery
RAID recovery requires understanding of:
- Stripe sizes and block sizes
- Parity rotation algorithms
- Drive ordering within the array
- File system structures across multiple drives
Incorrect reconstruction attempts can make professional recovery impossible.