A systems administrator is investigating reports of intermittent slow performance on a file server. Users report that accessing large files occasionally hangs, and nightly incremental backups have failed twice in the past week with read error messages. The administrator checks the system event logs and finds a steady increase in I/O errors and warnings specifically related to disk 3. The RAID controller's management utility reports the array as healthy and online, but S.M.A.R.T. predictive failure alerts have been logged for the same disk. Which of the following is the MOST likely cause of these issues?
The correct answer is impending physical drive failure. The combination of symptoms (slow performance, read errors, I/O errors) points to a storage issue with a specific disk. The key piece of information is the S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) predictive failure alert. S.M.A.R.T. is an internal monitoring system within the drive that warns of imminent mechanical or electronic failure. While a faulty cable, corrupt file system, or controller cache issue can cause performance problems, they would not generate a S.M.A.R.T. alert, which comes from the drive's own firmware. A RAID controller cache failure would typically affect the performance of the entire array and would not trigger alerts for a single, specific disk. A corrupt file system is a logical error, not a physical hardware error that S.M.A.R.T. detects. A faulty cable would cause communication errors but would not trigger an internal predictive failure warning from the drive itself.