5.2 Troubleshooting Storage Devices

Q: What indicates a read/write failure?

A: Errors like "Cannot read from the source disk."

Q: What are signs of slow storage performance?

A: Constant LED activity and repeated retries.

Q: What does loud clicking/grinding usually mean?

A: Mechanical HDD failure ("click of death") — drive is likely dead.

Q: What are first troubleshooting steps for disk failure?

1. Get a backup if possible

2. check cables

3. check for overheating

4. verify power supply.

Q: How do you run thorough disk diagnostics?

A: Use manufacturer diagnostics (may run overnight) preferably on a known-good computer.

Q: Why do HDDs make grinding/clicking noises?

A: Mechanical parts (spinning platters, actuator arms) with tight tolerances — metal-on-metal failure.

Q: What are symptoms when a drive is not recognized at boot?

A: "Boot device not found", no lights, beeps, or error messages if video works.

Q: What does "OS not found" mean?

A: Drive detected but no valid OS installed on that device.

Q: How do you troubleshoot boot failures?

A: Check cables, verify BIOS boot order, disable removable drives, check storage interfaces, try different SATA ports or another PC.

Q: Why is data recovery difficult from failed HDDs?

A: Mechanical failures are costly/time-consuming and recovery may fail — always maintain backups.

Q: How does a RAID failure typically present?

A: Clear alerts: error messages, emails, audible alarms; controller shows failed drive details.

Q: What must you do before replacing RAID drives?

A: Identify RAID type and check RAID console; don’t remove drives until you confirm which is bad.

Q: What does SMART do for drives?

A: Self-Monitoring, Analysis, and Reporting Technology — detects warning signs and enables scheduled checks.

Q: How should SMART be used?

A: Monitor metrics over time, enable automated notifications, back up and replace drives when metrics worsen.

Q: What causes long read/write times?

A: Delays can occur at memory, bus, spin-up, or device level — many possible bottlenecks.

Q: What is IOPS and example values?

A: Input/output operations per second; HDD ~200 IOPS, SSD up to ~1,000,000 IOPS (illustrative).

Q: What if an internal drive is missing in OS?

A: Check BIOS config/logs and reseat or replace cables; test drive in another computer.

Q: What to check for missing external drives?

A: Power and signal cables, drive enclosure, and USB/SATA connections.

Q: Why might mapped network drives disappear?

A: Reconnect-at-sign-in not enabled, login scripts failed, or network/server unavailable.

Q: What causes an array to appear missing?

A: Faulty or missing RAID controller, controller misconfiguration, or failed controller hardware.

Q: What info can a RAID controller provide?

A: Drive status (optimal/inactive), processor/memory, which keys to press, and configuration utility access.

Q: What’s the single best defense against storage failure?

A: Maintain recent, well-managed backups.