RAID Levels Explained: RAID 0, 1, 5, 10

RAID combines multiple drives for performance, redundancy, or both. But which RAID level is right for you? Fort Myers IT experts break down the most common options.

What is RAID?

RAID Basics

RAID (Redundant Array of Independent Disks) combines multiple physical drives into a single logical unit. Depending on configuration, it provides:

• Performance: Faster read/write by splitting data
• Redundancy: Protection if a drive fails
• Both: Some RAID levels offer both

Important Limitation

RAID is NOT a backup! It protects against drive failure, but not:

• Accidental deletion
• Ransomware/malware
• Fire, flood, or theft
• Multiple drive failures

Always maintain separate backups even with RAID.

Common RAID Levels

RAID 0 (Striping)

How it works: Data is split across drives for speed.

• Minimum drives: 2
• Capacity: 100% (all drives combined)
• Speed: Excellent (read and write)
• Redundancy: None! One drive failure loses everything

Best for: Video editing, gaming, scratch disks—where speed matters and data is backed up elsewhere.

RAID 1 (Mirroring)

How it works: Data is duplicated on all drives.

• Minimum drives: 2
• Capacity: 50% (half is used for mirror)
• Speed: Read speed improved, write speed unchanged
• Redundancy: Excellent (can lose one drive)

Best for: Small businesses, critical data, boot drives—where reliability matters more than capacity.

RAID 5 (Striping with Parity)

How it works: Data and parity information are striped across all drives.

• Minimum drives: 3
• Capacity: (N-1) drives—one drive worth is parity
• Speed: Good read, slower write
• Redundancy: Can lose one drive

Best for: General business use, file servers—good balance of performance, redundancy, and capacity.

RAID 6 (Double Parity)

How it works: Like RAID 5 but with two parity blocks.

• Minimum drives: 4
• Capacity: (N-2) drives
• Redundancy: Can lose two drives

Best for: Large arrays with big drives where rebuild failure is a risk.

RAID 10 (1+0, Mirrored Stripes)

How it works: Combines RAID 1 and RAID 0—pairs of mirrored drives are striped together.

• Minimum drives: 4
• Capacity: 50%
• Speed: Excellent (both read and write)
• Redundancy: Can lose one drive per mirror pair

Best for: Database servers, high-performance applications—when you need both speed and reliability.

Quick Comparison

RAID 0: 2 drives minimum, 100% capacity, Excellent speed, No fault tolerance

RAID 1: 2 drives minimum, 50% capacity, Good speed, 1 drive fault tolerance

RAID 5: 3 drives minimum, N-1 capacity, Good speed, 1 drive fault tolerance

RAID 6: 4 drives minimum, N-2 capacity, Fair speed, 2 drives fault tolerance

RAID 10: 4 drives minimum, 50% capacity, Excellent speed, 1 per pair fault tolerance

Our Recommendations

For Home Users

• Most don't need RAID—cloud backup is simpler
• If you want redundancy: RAID 1 on two drives
• For media server: RAID 5 on three or more drives

For Small Business

• File server: RAID 5 or RAID 6
• Database server: RAID 10
• Always combine with offsite backup

RONET Computer Repair in Fort Myers helps businesses design and implement storage solutions including RAID arrays. Whether you need a simple NAS for your office or a more complex server setup, we can recommend the right configuration for your needs.