1. What is RAID Array Capacity?

RAID (Redundant Array of Independent Disks) array capacity refers to the total usable storage space available in a RAID configuration after accounting for data redundancy and parity information.

2. How Does the Calculator Work?

The calculator uses the RAID capacity formula:

Where:

• \( Min\ Disk\ Size \) — The size of the smallest disk in the array (GB)
• \( Number\ of\ Disks \) — Total number of disks in the RAID array
• \( Parity\ Disks \) — Number of disks used for parity/redundancy

Explanation: The formula calculates usable storage capacity by subtracting the parity disks from the total disks and multiplying by the smallest disk size (which determines the usable capacity per disk in the array).

3. Importance of RAID Capacity Calculation

Details: Accurate RAID capacity calculation is essential for storage planning, ensuring adequate space for data storage, and understanding the trade-off between storage efficiency and data protection.

4. Using the Calculator

Tips: Enter the smallest disk size in GB, total number of disks, and number of parity disks. Ensure parity disks count is less than total disks count for valid calculation.

5. Frequently Asked Questions (FAQ)

Q1: Why use the smallest disk size in calculation?
A: In RAID arrays, all disks typically operate at the capacity of the smallest disk to maintain consistency across the array.

Q2: What are common RAID configurations?
A: Common configurations include RAID 0 (no parity), RAID 1 (mirroring, 1 parity disk per pair), RAID 5 (1 parity disk), and RAID 6 (2 parity disks).

Q3: Does this calculator work for all RAID levels?
A: This calculator provides a general formula that applies to most standard RAID configurations, but specific RAID implementations may have variations.

Q4: What happens if disks have different sizes?
A: The array will use the capacity of the smallest disk for all disks, with the excess capacity on larger disks remaining unused.

Q5: Can I add more disks to an existing RAID array?
A: This depends on the RAID controller and configuration. Some arrays support expansion, while others require rebuilding the entire array.