A technician is performing routine maintenance on a server that hosts multiple virtual machines. The server's hardware RAID controller utility reports a 'Predicted Drive Failure' for one of the SAS drives in a RAID 6 array. All other drives are currently healthy, and the array is operating normally. What is the BEST course of action?
- AOrder a replacement drive, then replace the predicted failing drive while the server is online (if supported).
- BWait for the drive to fail completely before replacing it.
- CRebuild the RAID array with the existing drives to clear the error.
- DImmediately shut down the server and replace the drive.
Show answer & explanationAnswer & explanation
Correct answer: A. Order a replacement drive, then replace the predicted failing drive while the server is online (if supported).
A 'Predicted Drive Failure' indicates that SMART data or other internal drive diagnostics predict an imminent failure, but the drive is still functional. RAID 6 can tolerate two drive failures. The best course of action is to proactively replace the predicted failing drive before it actually fails, preventing the array from entering a degraded state and maintaining full redundancy. This can often be done hot-swapping while the server is online, minimizing downtime.
Why the other options are wrong
- B. Waiting for complete failure increases risk. If another drive fails before the predicted one, the RAID 6 array could become critically degraded or fail entirely.
- C. Rebuilding the array with an existing predicted failing drive is counterproductive and risky. It puts stress on the potentially failing drive and does not address the underlying hardware issue.
- D. Shutting down the server unnecessarily disrupts operations when the drive is still predicted to fail, not actually failed. Hot-swapping is preferred if possible.
Predicted Drive Failure (SMART)
A warning from a drive's Self-Monitoring, Analysis, and Reporting Technology (SMART) that indicates an increased likelihood of imminent drive failure, even if the drive is currently functional.
- Allows for proactive replacement to prevent actual data loss or performance degradation.
- Commonly reported by hardware RAID controllers or OS utilities.
- Hot-swapping is often possible for enterprise drives in RAID arrays.
- Ignoring these warnings significantly increases risk.
Memory trick: Predicted failure? Replace it before the crystal ball shatters!