1. What is RAID Capacity Calculation?

RAID (Redundant Array of Independent Disks) capacity calculation determines the usable storage space in a RAID array after accounting for redundancy. The formula considers the smallest disk size, total number of disks, and number of parity disks used for data protection.

2. How Does the Calculator Work?

The calculator uses the RAID capacity formula:

Where:

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

Explanation: The formula calculates the effective storage capacity by subtracting the parity disks from the total disk count and multiplying by the smallest disk size (which determines the usable space on all disks).

3. Importance of RAID Capacity Planning

Details: Proper RAID capacity planning is essential for storage infrastructure design, ensuring adequate space for data storage while maintaining desired levels of redundancy and performance across different RAID configurations.

4. Using the Calculator

Tips: Enter the smallest disk size in GB, total number of disks, and number of parity disks. All values must be valid (disk size > 0, number of disks > 0, parity disks between 0 and total disks-1).

5. Frequently Asked Questions (FAQ)

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

Q2: How does this apply to different RAID levels?
A: Different RAID levels use different numbers of parity disks (RAID 1: 1 parity, RAID 5: 1 parity, RAID 6: 2 parity, etc.).

Q3: What about RAID 0 arrays?
A: RAID 0 has no parity disks (0), so capacity equals the sum of all disk capacities.

Q4: Does this account for formatting overhead?
A: No, this calculates raw capacity. Actual usable space will be slightly less due to filesystem overhead.

Q5: Can I mix different sized disks in RAID?
A: Yes, but the array will use the smallest disk's capacity for all disks, potentially wasting space on larger drives.