Examkin

Question

Difficulty: Very hardStorage Drives and RAID Array Issues

A database administrator reports performance degradation on a enterprise server utilizing a dedicated hardware RAID 10 array composed of four enterprise NVMe SSDs. The out-of-band management console shows that the array status is currently online, but Disk 2 (the mirrored pair to Disk 0) has logged a S.M.A.R.T. predictive failure warning indicating high media errors. Which of the following is the most appropriate immediate action for the technician to take to resolve the issue while minimizing service disruption and preventing data loss?

  1. Hot-swap the failing Disk 2 with an identical NVMe SSD and monitor the controller rebuild process while the system remains live.Answer
  2. B
    Back up the array data, break the RAID 10 configuration in the controller firmware, format all four SSDs, and restore from the backup.
  3. C
    Force Disk 0 and Disk 2 offline simultaneously through the operating system disk management console to perform low-level sector repairs.
  4. D
    Unmount the file system and clear the drive's S.M.A.R.T. log markers via the RAID utility to force the controller to clear the warning status.

Answer

Hot-swap the failing drive with an identical drive and allow the hardware controller to rebuild the mirrored pair while online.
In a RAID 10 array, each pair of drives is mirrored (RAID 1) and then striped (RAID 0). When a single drive in a pair issues a S.M.A.R.T. predictive failure warning, the array remains operational because its mirrored partner holds a complete copy of the data. Performing an online hot-swap of the failing drive allows the hardware controller to copy the data from the remaining healthy partner onto the new replacement drive, restoring full fault tolerance with minimal risk and zero downtime.

Step-by-Step Solution

1
Analyze the RAID configuration and failure alert.
Identified a RAID 10 array where Disk 2 (mirrored to Disk 0) has a S.M.A.R.T. predictive failure warning, but the array is still functional and online.
RAID 10 provides fault tolerance through mirroring. Disk 0 contains an exact copy of Disk 2's data.
2
Determine the optimal hot-swappable recovery procedure.
Identify that replacing Disk 2 while online (hot-swapping) triggers the hardware controller to rebuild Disk 2 from Disk 0.
Hot-swapping maintains uptime and leverages built-in redundancy to reconstruct the mirror set without breaking the array.
3
Evaluate alternative procedural actions for potential risks.
Discard actions that involve formatting, clearing configuration, or taking both mirrored members offline.
Destructive actions or taking both drives in a mirrored pair offline cause unnecessary downtime or catastrophic data loss.

Key Concept

Handling Predictive Drive Failures in Redundant RAID Arrays
Rate this question

Topics

Storage Drives and RAID Array Issues

More questions from this topic