1. What is RAID 5 Effective Storage Calculator?

Definition: This calculator estimates the usable storage capacity in a RAID 5 array based on the number of drives and their individual sizes.

Purpose: It helps IT professionals and storage administrators plan their storage arrays and understand the available capacity after RAID 5 parity overhead.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Effective} \) — Usable storage capacity (TB)
• \( N \) — Number of drives in the array
• \( \text{DriveSize} \) — Capacity of each individual drive (TB)

Explanation: RAID 5 uses distributed parity which requires the equivalent of one drive's capacity for parity information, hence the (N-1) multiplier.

3. Importance of RAID 5 Storage Calculation

Details: Proper storage calculation ensures accurate capacity planning, cost estimation, and meets performance requirements while maintaining data redundancy.

4. Using the Calculator

Tips: Enter the number of drives (minimum 3) and the size of each drive in TB. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why does RAID 5 need (N-1) calculation?
A: RAID 5 dedicates the equivalent of one drive's capacity for parity data that's distributed across all drives for fault tolerance.

Q2: What's the minimum number of drives for RAID 5?
A: RAID 5 requires a minimum of 3 drives to implement the distributed parity scheme.

Q3: Can I mix different drive sizes in RAID 5?
A: Technically yes, but the array will treat all drives as having the capacity of the smallest drive in the array.

Q4: How does this compare to RAID 1 or RAID 6?
A: RAID 1 (mirroring) has 50% efficiency, RAID 5 has (N-1)/N efficiency, and RAID 6 has (N-2)/N efficiency but can tolerate two drive failures.

Q5: Does this include formatting overhead?
A: No, this is raw capacity. Actual usable space will be slightly less due to filesystem overhead.