Windows 2000 Server (Disk Management, RAID-5 recovery): A four-disk stripe set with parity was converted to a dynamic RAID-5 volume months ago. Today, access is slow and Disk Management shows the third disk status as “Missing.” To recover the degraded RAID-5 volume properly, what should you do first?

Introduction / Context:
When a Windows 2000 dynamic RAID-5 volume reports that one member disk is “Missing,” the array is operating in a degraded state and performance will drop because parity reconstruction is required for reads. The safest first response is to confirm whether the disk is truly failed or simply offline or disconnected, and then use Disk Management's built-in recovery steps before replacing hardware.

Given Data / Assumptions:

• Dynamic disks are used; the RAID-5 set was converted from a stripe with parity.
• The third disk shows status “Missing,” not “Failed.”
• Users noticed slower access since yesterday (consistent with degraded RAID-5).
• Goal: recover the volume without unnecessary rebuilds or data loss.

Concept / Approach:
In Windows 2000 Disk Management, “Missing” indicates the OS cannot currently see the disk (cable/power/offline), whereas “Failed” indicates the dynamic disk database is reachable but the device reports failure. The correct first action is to ensure power/cabling is intact and then use Reactivate Disk, which attempts to bring the dynamic disk online and rejoin it to the set without a full replacement.

Step-by-Step Solution:
Physically verify the third disk: check power, data cables, controller visibility.Open Disk Management; right-click the “Missing” disk and choose Reactivate Disk.Confirm the disk status transitions to Online and the RAID-5 volume returns to Healthy/Regenerating.Allow RAID-5 to resynchronize if needed; monitor event logs for disk errors.

Verification / Alternative check:
If Reactivate Disk fails or the disk repeatedly drops, run hardware diagnostics and consider replacing the disk. After replacement, use Disk Management to repair the volume by adding the new disk so parity can rebuild.

Why Other Options Are Wrong:
Replace the disk immediately: Premature; “Missing” may be cabling/power, not failure.

Repair Volume before reactivation: Repair requires an available target; Reactivate is the proper first step for a “Missing” disk.

Create extended partition and let auto-repair: Not a supported or reliable workflow for dynamic RAID-5 recovery.

None of the above: Incorrect because reactivation is the standard first step.

Common Pitfalls:
Confusing “Missing” with “Failed,” replacing disks unnecessarily, or attempting a repair while the original member is simply offline due to a loose cable.

Final Answer:
Verify the third disk is attached and powered on; then use Disk Management to Reactivate Disk