1. What is a RAID 5 vs 6 Capacity Calculator?

Definition: This calculator shows the capacity difference between RAID 5 and RAID 6 configurations for a given drive size.

Purpose: Helps storage administrators and IT professionals understand the capacity trade-off when choosing between RAID 5 and RAID 6.

2. How Does the Calculator Work?

The calculator uses the simple formula:

Where:

• \( DiffCapacity \) — Capacity difference between RAID 5 and 6 (TB)
• \( DriveSize \) — Size of individual drives in the array (TB)

Explanation: RAID 6 uses capacity equivalent to two drives for parity (dual parity), while RAID 5 uses only one drive's worth of capacity for parity (single parity).

3. Importance of RAID Capacity Calculation

Details: Understanding this difference helps in storage planning, cost estimation, and choosing the right RAID level for your redundancy needs.

4. Using the Calculator

Tips: Enter the size of individual drives in your RAID array (in TB). The result shows how much more capacity RAID 5 provides compared to RAID 6.

5. Frequently Asked Questions (FAQ)

Q1: Why does RAID 6 have less capacity than RAID 5?
A: RAID 6 stores two parity blocks per stripe (dual parity) for better fault tolerance, while RAID 5 stores only one (single parity).

Q2: Is this calculation the same regardless of drive count?
A: Yes, the difference is always equal to one drive's capacity, regardless of how many drives are in the array.

Q3: When should I choose RAID 5 over RAID 6?
A: RAID 5 is suitable when you prioritize capacity over redundancy, with smaller arrays or less critical data.

Q4: When should I choose RAID 6 over RAID 5?
A: RAID 6 is better for larger arrays or critical data where you need protection against two simultaneous drive failures.

Q5: How does this translate to usable capacity?
A: For an N-drive array: RAID 5 usable = (N-1)*DriveSize, RAID 6 usable = (N-2)*DriveSize.