What does rising CRC error count usually indicate?

• A. Drive overheating.
• B. Self-test failure.
• C. Usually bad/loose SATA/SAS cable — not necessarily drive failure.
• D. Wear leveling.

Answer: (C)

CRC errors measure the integrity of the data link between the host controller and the drive. When the Cyclic Redundancy Check fails on frames transmitted over SATA/SAS, the system cannot trust the data on that link and must retry, so you see the error count rise. This is a symptom of a problem on the communication path, not necessarily the disk itself. The most common cause is a bad or loose cable or a poor connection on the SATA/SAS interface, though faulty connectors or interference can also trigger CRC errors. Because of that, the typical fix is to reseat or replace the cable, test with a different port, or swap in a known-good cable to isolate the issue. Overheating would affect drive health and SMART attributes, self-test failures point to internal drive testing results, and wear leveling relates to SSD flash management—none of these directly explain a rising CRC error count on the link.