Which is a typical warning sign before drive failure?

• A. Rising pending sectors or reallocated sectors.
• B. Decreasing spin retries.
• C. CRC errors increasing.
• D. Increasing throughput.

Answer: (A)

Rising pending sectors or reallocated sectors is a clear warning that the drive’s surface is deteriorating. When a sector can’t be read, the drive first marks it as pending to verify later. If the data is confirmed unreadable, that sector is remapped to a spare, creating a reallocated sector. Seeing both counts climb indicates the disk is encountering more unreadable areas and is progressively reallocating more sectors to maintain operation. This is a classic sign that the drive is failing or on the verge of failure, so you should back up important data immediately and plan for replacement.

CRC errors increasing point to data integrity problems on the data path, which can stem from a bad cable or controller issue rather than the disk itself. Decreasing spin retries would imply the drive is overcoming spin-up challenges rather than showing a failure trend. Increasing throughput isn’t a failure indicator and usually reflects changes in workload or caching, not impending disk failure.